The most familiar form of electromagnetic energy is sunlight. The frequency of sunlight (visible light) is the dividing line between the more potent, ionizing radiation (x rays, cosmic rays) at higher frequencies and the more benign, non-ionizing radiation at lower frequencies. There is a spectrum of non-ionizing radiation. Within the context of this chapter, at the high end just below visible light is infrared radiation. Below that is the broad range of radio frequencies, which includes (in descending order) microwaves, cellular radio, television, FM radio and AM radio, short waves used in dielectric and induction heaters and, at the low end, fields with power frequency. The electromagnetic spectrum is illustrated in figure 1. 

Figure 1. The electromagnetic spectrum

ELF010F1

Just as visible light or sound permeates our environment, the space where we live and work, so do the energies of electromagnetic fields. Also, just as most of the sound energy we are exposed to is created by human activity, so too are the electromagnetic energies: from the weak levels emitted from our everyday electrical appliances—those that make our radio and TV sets work—to the high levels that medical practitioners apply for beneficial purposes—for example, diathermy (heat treatments). In general, the strength of such energies decreases rapidly with distance from the source. Natural levels of these fields in the environment are low.

Non-ionizing radiation (NIR) incorporates all radiation and fields of the electromagnetic spectrum that do not have enough energy to produce ionization of matter. That is, NIR is incapable of imparting enough energy to a molecule or atom to disrupt its structure by removing one or more electrons. The borderline between NIR and ionizing radiation is usually set at a wavelength of approximately 100 nanometres.

As with any form of energy, NIR energy has the potential to interact with biological systems, and the outcome may be of no significance, may be harmful in different degrees, or may be beneficial. With radiofrequency (RF) and microwave radiation, the main interaction mechanism is heating, but in the low-frequency part of the spectrum, fields of high intensity may induce currents in the body and thereby be hazardous. The interaction mechanisms for low-level field strengths are, however, unknown.

 

 

 

 

 

 

 

 

Quantities and Units

Fields at frequencies below about 300 MHz are quantified in terms of electric field strength (E) and magnetic field strength (H). E is expressed in volts per metre (V/m) and H in amperes per metre (A/m). Both are vector fields—that is, they are characterized by magnitude and direction at each point. For the low-frequency range the magnetic field is often expressed in terms of the flux density, B, with the SI unit tesla (T). When the fields in our daily environment are discussed, the subunit microtesla (μT) is usually the preferred unit. In some literature the flux density is expressed in gauss (G), and the conversion between these units is (for fields in air):

1 T = 104 G or 0.1 μT = 1 mG and 1 A/m = 1.26 μT.

Reviews of concepts, quantities, units and terminology for non-ionizing radiation protection, including radiofrequency radiation, are available (NCRP 1981; Polk and Postow 1986; WHO 1993).

The term radiation simply means energy transmitted by waves. Electromagnetic waves are waves of electric and magnetic forces, where a wave motion is defined as propagation of disturbances in a physical system. A change in the electric field is accompanied by a change in the magnetic field, and vice versa. These phenomena were described in 1865 by J.C. Maxwell in four equations which have come to be known as Maxwell’s Equations.

Electromagnetic waves are characterized by a set of parameters that include frequency (f), wavelength (λ), electric field strength, magnetic field strength, electric polarization (P) (the direction of the E field), velocity of propagation (c) and Poynting vector (S). Figure 2  illustrates the propagation of an electromagnetic wave in free space. The frequency is defined as the number of complete changes of the electric or magnetic field at a given point per second, and is expressed in hertz (Hz). The wavelength is the distance between two consecutive crests or troughs of the wave (maxima or minima). The frequency, wavelength and wave velocity (v) are interrelated as follows:

v = f λ

Figure 2. A plane wave propagating with the speed of light in the x-direction

ELF010F2

The velocity of an electromagnetic wave in free space is equal to the velocity of light, but the velocity in materials depends on the electrical properties of the material—that is, on its permittivity (ε) and permeability (μ). The permittivity concerns the material interactions with the electric field, and the permeability expresses the interactions with the magnetic field. Biological substances have permittivities that differ vastly from that of free space, being dependant on wavelength (especially in the RF range) and tissue type. The permeability of biological substances, however, is equal to that of free space.

In a plane wave, as illustrated in figure 2 , the electric field is perpendicular to the magnetic field and the direction of propagation is perpendicular to both the electric and the magnetic fields.

 

 

 

For a plane wave, the ratio of the value of the electric field strength to the value of the magnetic field strength, which is constant, is known as the characteristic impedance (Z):

Z = E/H

In free space, Z= 120π ≈ 377Ω but otherwise Z depends on the permittivity and permeability of the material the wave is travelling through.

Energy transfer is described by the Poynting vector, which represents the magnitude and direction of the electromagnetic flux density:

S = E x H

For a propagating wave, the integral of S over any surface represents the instantaneous power transmitted through this surface (power density). The magnitude of the Poynting vector is expressed in watts per square metre (W/m2) (in some literature the unit mW/cm2 is used—the conversion to SI units is 1 mW/cm2 = 10 W/m2) and for plane waves is related to the values of the electric and magnetic field strengths:

S = E2 / 120π = E2 / 377

and

S =120π H2 = 377 H2

Not all exposure conditions encountered in practice can be represented by plane waves. At distances close to sources of radio-frequency radiation the relationships characteristic of plane waves are not satisfied. The electromagnetic field radiated by an antenna can be divided into two regions: the near-field zone and the far-field zone. The boundary between these zones is usually put at:

r = 2a2 / λ

where a is the greatest dimension of the antenna.

In the near-field zone, exposure has to be characterized by both the electric and the magnetic fields. In the far-field one of these suffices, as they are interrelated by the above equations involving E and H. In practice, the near-field situation is often realized at frequencies below 300 Mhz.

Exposure to RF fields is further complicated by interactions of electromagnetic waves with objects. In general, when electromagnetic waves encounter an object some of the incident energy is reflected, some is absorbed and some is transmitted. The proportions of energy transmitted, absorbed or reflected by the object depend on the frequency and polarization of the field and the electrical properties and shape of the object. A superimposition of the incident and reflected waves results in standing waves and spatially non-uniform field distribution. Since waves are totally reflected from metallic objects, standing waves form close to such objects.

Since the interaction of RF fields with biological systems depends on many different field characteristics and the fields encountered in practice are complex, the following factors should be considered in describing exposures to RF fields:

  • whether exposure occurs in the near- or far-field zone
  • if near-field, then values for both E and H are needed; if far-field, then either E or H
  • spatial variation of the magnitude of the field(s)
  • field polarization, that is, the direction of the electric field with respect to the direction of wave propagation.

 

For exposure to low-frequency magnetic fields it is still not clear whether the field strength or flux density is the only important consideration. It may turn out that other factors are also important, such as the exposure time or the rapidity of the field changes.

The term electromagnetic field (EMF), as it is used in the news media and popular press, usually refers to electric and magnetic fields at the low-frequency end of the spectrum, but it can also be used in a much broader sense to include the whole spectrum of electromagnetic radiation. Note that in the low-frequency range the E and B fields are not coupled or interrelated in the same way that they are at higher frequencies, and it is therefore more accurate to refer to them as “electric and magnetic fields” rather than EMFs.

 

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In recent years interest has increased in the biological effects and possible health outcomes of weak electric and magnetic fields. Studies have been presented on magnetic fields and cancer, on reproduction and on neurobehavioural reactions. In what follows, a summary is given of what we know, what still needs to be investigated and, particularly, what policy is appropriate—whether it should involve no restrictions of exposure at all, “prudent avoidance” or expensive interventions.

What we Know

Cancer

Epidemiological studies on childhood leukaemia and residential exposure from power lines seem to indicate a slight risk increase, and excess leukaemia and brain tumour risks have been reported in “electrical” occupations. Recent studies with improved techniques for exposure assessment have generally strengthened the evidence of an association. There is, however, still a lack of clarity as to exposure characteristics—for example, magnetic field frequency and exposure intermittence; and not much is known about possible confounding or effect-modifying factors. Furthermore, most of the occupational studies have indicated one special form of leukaemia, acute myeloid leukaemia, while others have found higher incidences for another form, chronic lymphatic leukaemia. The few animal cancer studies reported have not given much help with risk assessment, and in spite of a large number of experimental cell studies, no plausible and understandable mechanism has been presented by which a carcinogenic effect could be explained.

Reproduction, with special reference to pregnancy outcomes

In epidemiological studies, adverse pregnancy outcomes and childhood cancer have been reported after maternal as well as paternal exposure to magnetic fields, the paternal exposure indicating a genotoxic effect. Efforts to replicate positive results by other research teams have not been successful. Epidemiological studies on visual display unit (VDU) operators, who are exposed to the electric and magnetic fields emitted by their screens, have been mainly negative, and animal teratogenic studies with VDU-like fields have been too contradictory to support trustworthy conclusions.

Neurobehavioural reactions

Provocation studies on young volunteers seem to indicate such physiological changes as slowing of heart rate and electroencephalogram (EEG) changes after exposure to relatively weak electric and magnetic fields. The recent phenomenon of hypersensitivity to electricity seems to be multifactorial in origin, and it is not clear whether the fields are involved or not. A great variety of symptoms and discomforts has been reported, mainly of the skin and the nervous system. Most of the patients have diffuse skin complaints in the face, such as flush, rosiness, ruddiness, heat, warmth, pricking sensations, ache and tightness. Symptoms associated with the nervous system are also described, such as headache, dizziness, fatigue and faintness, tingling and pricking sensations in the extremities, shortness of breath, heart palpitations, profuse sweatings, depressions and memory difficulties. No characteristic organic neurological disease symptoms have been presented.

Exposure

Exposure to fields occurs throughout society: in the home, at work, in schools and by the operation of electrically powered means of transport. Wherever there are electric wires, electric motors and electronic equipment, electric and magnetic fields are created. Average workday field strengths of 0.2 to 0.4 μT (microtesla) appear to be the level above which there could be an increased risk, and similar levels have been calculated for annual averages for subjects living under or near power lines.

Many people are similarly exposed above these levels, though for shorter periods, in their homes (via electric radiators, shavers, hair-dryers and other household appliances, or stray currents due to imbalances in the electrical grounding system in a building), at work (in certain industries and offices involving proximity to electric and electronic equipment) or while travelling in trains and other electrically driven conveyances. The importance of such intermittent exposure is not known. There are other uncertainties as to exposure (involving questions relating to the importance of field frequency, to other modifying or confounding factors, or to knowledge of the total exposure day and night) and effect (given the consistency in findings as to type of cancer), and in the epidemiological studies, which make it necessary to evaluate all risk assessments with great caution.

Risk assessments

In Scandinavian residential studies, results indicate a doubled leukaemia risk above 0.2 μT, the exposure levels corresponding to those typically encountered within 50 to 100 metres of an overhead power line. The number of childhood leukaemia cases under power lines are few, however, and the risk is therefore low compared to other environmental hazards in society. It has been calculated that each year in Sweden there are two cases of childhood leukaemia under or near power lines. One of these cases may be attributable to the magnetic field risk, if any.

Occupational exposures to magnetic fields are generally higher than residential exposures, and calculations of leukaemia and brain tumour risks for exposed workers give higher values than for children living close to power lines. From calculations based on the attributable risk discovered in a Swedish study, approximately 20 cases of leukaemia and 20 cases of brain tumours could be attributed to magnetic fields each year. These figures are to be compared with the total number of 40,000 annual cancer cases in Sweden, of which 800 have been calculated to have an occupational origin.

What Still Needs to be Investigated

It is quite clear that more research is needed in order to secure a satisfactory understanding of the epidemiological study results obtained so far. There are additional epidemiological studies in progress in different countries around the world, but the question is whether these will add more to the knowledge we already have. As a matter of fact it is not known which characteristics of the fields are causal to the effects, if any. Thus, we definitely need more studies on possible mechanisms to explain the findings we have assembled.

There are in the literature, however, a vast number of in vitro studies devoted to the search for possible mechanisms. Several cancer promotion models have been presented, based on changes in the cell surface and in the cell membrane transport of calcium ions, disruption of cell communication, modulation of cell growth, activation of specific gene sequences by modulated ribonucleic acid (RNA) transcription, depression of pineal melatonin production, modulation of ornithine decarboxylase activity and possible disruption of hormonal and immune-system anti-tumour control mechanisms. Each of these mechanisms has features applicable to explaining reported magnetic field cancer effects; however, none has been free of problems and essential objections.

Melatonin and magnetite

There are two possible mechanisms that may be relevant to cancer promotion and thus deserve special attention. One of these has to do with the reduction of nocturnal melatonin levels induced by magnetic fields and the other is related to the discovery of magnetite crystals in human tissues.

It is known from animal studies that melatonin, via an effect on circulating sex hormone levels, has an indirect oncostatic effect. It has also been indicated in animal studies that magnetic fields suppress pineal melatonin production, a finding that suggests a theoretical mechanism for the reported increase in (for example) breast cancer that may be due to exposure to such fields. Recently, an alternative explanation for the increased cancer risk has been proposed. Melatonin has been found to be a most potent hydroxyl radical scavenger, and consequently the damage to DNA that might be done by free radicals is markedly inhibited by melatonin. If melatonin levels are suppressed, for example by magnetic fields, the DNA is left more vulnerable to oxidative attack. This theory explains how the depression of melatonin by magnetic fields could result in a higher incidence of cancer in any tissue.

But do human melatonin blood levels diminish when individuals are exposed to weak magnetic fields? There exist some indications that this may be so, but further research is needed. For some years it has been known that the ability of birds to orient themselves during seasonal migrations is mediated via magnetite crystals in cells that respond to the earth’s magnetic field. Now, as mentioned above, magnetite crystals have also been demonstrated to exist in human cells in a concentration high enough theoretically to respond to weak magnetic fields. Thus the role of magnetite crystals should be considered in any discussions on the possible mechanisms that may be proposed as to the potentially harmful effects of electric and magnetic fields.

The need for knowledge on mechanisms

To summarize, there is a clear need for more studies on such possible mechanisms. Epidemiologists need information as to which characteristics of the electric and magnetic fields they should focus upon in their exposure assessments. In most epidemiological studies, mean or median field strengths (with frequencies of 50 to 60 Hz) have been used; in others, cumulative measures of exposure were studied. In a recent study, fields of higher frequencies were found to be related to risk. In some animal studies, finally, field transients have been found to be important. For epidemiologists the problem is not on the effect side; registers on diseases exist in many countries today. The problem is that epidemiologists do not know the relevant exposure characteristics to consider in their studies.

What Policy is Appropriate

Systems of protection

Generally, there are different systems of protection to be considered with respect to regulations, guidelines and policies. Most often the health-based system is selected, in which a specific adverse health effect can be identified at a certain exposure level, irrespective of exposure type, chemical or physical. A second system could be characterized as an optimization of a known and accepted hazard, which has no threshold below which the risk is absent. An example of an exposure falling within this kind of system is ionizing radiation. A third system covers hazards or risks where causal relationships between exposure and outcome have not been shown with reasonable certainty, but for which there are general concerns about possible risks. This lattermost system of protection has been denoted the principle of caution, or more recently prudent avoidance, which can be summarized as the future low-cost avoidance of unnecessary exposure in the absence of scientific certainty. Exposure to electric and magnetic fields has been discussed in this way, and systematic strategies have been presented, for instance, on how future power lines should be routed, workplaces arranged and household appliances designed in order to minimize exposure.

It is apparent that the system of optimization is not applicable in connection with restrictions of electric and magnetic fields, simply because they are not known and accepted as risks. The other two systems, however, are both presently under consideration.

Regulations and guidelines for restriction of exposure under the health-based system

In international guidelines limits for restrictions of field exposure are several orders of magnitude above what can be measured from overhead power lines and found in electrical occupations. The International Radiation Protection Association (IRPA) issued Guidelines on limits of exposure to 50/60 Hz electric and magnetic fields in 1990, which has been adopted as a basis for many national standards. Since important new studies were published thereafter, an addendum was issued in 1993 by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Furthermore, in 1993 risk assessments in agreement with that of IRPA were also made in the United Kingdom.

These documents emphasize that the state of scientific knowledge today does not warrant limiting exposure levels for the public and the workforce down to the μT level, and that further data are required to confirm whether or not health hazards are present. The IRPA and ICNIRP guidelines are based on the effects of field-induced currents in the body, corresponding to those normally found in the body (up to about 10 mA/m2). Occupational exposure to magnetic fields of 50/60 Hz is recommended to be limited to 0.5 mT for all-day exposure and 5 mT for short exposures of up to two hours. It is recommended that exposure to electric fields be limited to 10 and 30 kV/m. The 24-hour limit for the public is set at 5 kV/m and 0.1 mT.

These discussions on the regulation of exposure are based entirely on cancer reports. In studies of other possible health effects related to electric and magnetic fields (for example, reproductive and neurobehavioural disorders), results are generally considered insufficiently clear and consistent to constitute a scientific basis for restricting exposure.

The principle of caution or prudent avoidance

There is no real difference between the two concepts; prudent avoidance has been used more specifically, though, in discussions of electric and magnetic fields. As said above, prudent avoidance can be summarized as the future, low-cost avoidance of unnecessary exposure as long as there is scientific uncertainty about the health effects. It has been adopted in Sweden, but not in other countries.

In Sweden, five government authorities (the Swedish Radiation Protection Institute; the National Electricity Safety Board; the National Board of Health and Welfare; the National Board of Occupational Safety and Health; and the National Board of Housing, Building and Planning) jointly have stated that “the total knowledge now accumulating justifies taking steps to reduce field power”. Provided the cost is reasonable, the policy is to protect people from high magnetic exposures of long duration. During the installation of new equipment or new power lines that may cause high magnetic field exposures, solutions giving lower exposures should be chosen provided these solutions do not imply large inconveniences or costs. Generally, as stated by the Radiation Protection Institute, steps can be taken to reduce the magnetic field in cases where the exposure levels exceed the normally occurring levels by more than a factor of ten, provided such reductions can be done at a reasonable cost. In situations where the exposure levels from existing installations do not exceed the normally occurring levels by a factor of ten, costly rebuilding should be avoided. Needless to say, the present avoidance concept has been criticized by many experts in different countries, such as by experts in the electricity supply industry.

Conclusions

In the present paper a summary has been given of what we know on the possible health effects of electric and magnetic fields, and what still needs to be investigated. No answer has been given to the question of which policy should be adopted, but optional systems of protection have been presented. In this connection, it seems clear that the scientific database at hand is insufficient to develop limits of exposure at the μT level, which means in turn that there are no reasons for expensive interventions at these exposure levels. Whether some form of strategy of caution (e.g., prudent avoidance) should be adopted or not is a matter for decisions by public and occupational health authorities of individual countries. If such a strategy is not adopted it usually means that no restrictions of exposure are imposed because the health-based threshold limits are well above everyday public and occupational exposure. So, if opinions differ today as to regulations, guidelines and policies, there is a general consensus among standard setters that more research is needed to get a solid basis for future actions.

 

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Tuesday, 15 March 2011 14:38

Case Study: Outdoor Markets

The informal sector accounts for between 20 and 70% of the urban workforce in developing countries (with the average being 40%); and the traders and hawkers of outdoor markets comprise a significant portion of this sector. Such work is by its very nature precarious. It involves long hours and low pay. Average earnings may not total 40% of levels found in the formal sector. Not only do many workers in outdoor markets lack permanent locations to conduct their business, they also may be compelled to do without supporting infrastructural facilities. They do not enjoy the same legal protection or social insurance as workers in the formal sector and are subject to harassment. Occupationally related morbidity and mortality rates generally go unrecorded (Bequele 1985).

Figure 1. Outdoor food market in Malatia, Solomon Islands, 1995

OFR040F1

C. Geefhuyson

Workers in outdoor markets in both developing and developed countries, such as those shown in figure 1 and figure 2 , are exposed to numerous health and safety hazards. They are exposed to exhaust from motor vehicles, which contains such things as carbon monoxide and polycyclic aromatic hydrocarbons. Workers are also exposed to the weather. In tropical and desert locations they are subject to heat stress and dehydration. In cooler climates they are exposed to freezing temperatures, which can cause problems such as numbness, shivering and frostbite. Workers in outdoor markets may not have access to adequate hygiene facilities.

Figure 2. Heavy baskets of sea urchins being distributed by a small operator-owner, Japan, 1989

OFR040F2

L. Manderson

The informal sector generally and outdoor markets specifically involve child labour. Roughly 250 million children are engaged in full- and part-time work around the world (ILO 1996); street traders are the most visible child workers. Children who work, including street traders, typically are denied education and often are forced to perform tasks, such as lifting heavy loads, which can result in permanent disabilities.

 

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Tuesday, 15 March 2011 14:32

The Retail Industry

The retail trade is the selling of goods to consumers. Enterprises sell everything from automobiles to clothing, from food to television sets. In many countries what once was an industry comprised mainly of small shops and stores, now largely consists of multinational conglomerates which own huge megastores competing for the global market. Competition and technological changes have changed job descriptions, the hazards associated with those jobs and the nature of the workforce itself.

In the developed nations, small retailers struggle to compete with large corporate retailers. In the United States, Canada and throughout the European Community and the Pacific Rim, the retail trade has moved from the city centre to suburban shopping malls. Instead of the neighbourhood “mom and pop” stores, multinational chain stores sell the same products and the same brand names, effectively limiting consumer choice of product and forcing competition out of the market by their buying power, advertising capabilities and lower prices. Many times a large store will take a loss on certain products in order to bring customers into a store; this technique frequently generates other sales.

In developing countries with predominantly agrarian economies, bartering systems and open marketplaces are still common. However, in many developing countries, the large multinational retailers are beginning to enter the retail market.

Each type of establishment has its own hazards. Retail work in developing countries and countries in transition is often very different from retail work in developed countries; conglomerates with large chain stores are not yet dominant and retail work is mainly conducted in an open-air market, in all types of weather.

There is a trend among multinational conglomerates to try and change employment conditions: trade unionism is discouraged, staff is reduced to a bare minimum, wages go down, stores predominantly hire part-time workers, the average age of the workforce is lowered and benefit packages diminish.

Throughout the world store opening hours have changed so that some establishments even remain open 24 hours a day, 7 days per week. In the past, a worker who worked late at night or on a holiday received extra compensation; now, premium pay for working those hours has been taken away as such long hours become the norm. In the US, for example, traditional holidays are now negotiable when the store stays open on a 24-hour, 7-day basis.

The changes in the nature of how business is conducted has forced several fundamental changes in the workforce. Since many jobs have been marginalized to part-time work, the jobs themselves require little skill and workers receive no training. Workers who once saw a career in retail work, now find themselves changing jobs frequently or even leaving the field of retail work, which has become short term and part time.

The size of the workforce in the retail industry is difficult to estimate. The informal sector plays a significant role in developing countries (see “Case Study: Outdoor Markets”). Many times, health and safety problems go unnoticed, are not recorded by government and are considered to be part of the job.

In many of the countries that do keep statistics, retail, wholesale and restaurant and hotel workers are grouped into one category. Statistics from around the world show that the percentage of people who work in the wholesale, retail, restaurant and hotel trades ranges from over 20% in some countries in Asia to less than 3% in Burkina Faso (see table 1 ). Although men outnumber women in the labour force, the percentage of women in the retail industry is higher in at least half of the countries for which statistics are available.

Table 1. Labour statistics in the retail industry (selected countries)

Country

Men in the labour force (%)

Men in
wholesale
and retail trade;
restaurants and
hotels (%)

Women in the labour force (%)

Women in
wholesale
and retail trade;
restaurants and
hotels (%)

Total population in
wholesale and retail
trade; restaurants
and hotels (%)

Total number
of people
injured

Injured people
in the retail
industry (%)

Burkina Faso

51.3

1.0

48.7

1.5

2.6

1,858

8.71

Costa Rica

69.9

11.0

30.1

7.4

18.4

156,782

7.02

Egypt

75.9

7.3

24.1

1.2

8.4

60,859

2.52

Germany

52.3

4.5

47.7

7.0

11.5

29,847

20.13

Greece

63.0

10.9

37.0

7.0

17.0

23,959

10.54

Italy

63.1

11.7

36.9

6.9

8.6

767,070

8.15

Japan

59.5

11.0

40.5

10.9

21.9

2,245

9.7

Mexico

69.1

10.8

30.9

9.6

20.5

456,843

16.96

Netherlands

58.9

9.1

41.1

8.0

17.1

64,657

16.5

Norway

54.5

7.9

45.5

8.9

16.7

26,473

5.0

Singapore

59.8

13.2

40.2

9.0

22.0

4,019

0.27

Sweden

52.0

6.8

48.0

6.5

13.3

43,459

6.6

Thailand

55.5

5.8

49.5

6.8

12.6

103,296

3.18

United Kingdom

56.2

8.3

43.8

9.5

17.8

157,947

11.09

United States

54

11.1

46.0

10.0

21

295,340

23.610

1 Including commuting accidents; including occupational diseases.
2 Including commuting accidents; establishments employing 100 or more workers.
3 The series related to the territory of the Federal Republic of Germany before 1990;
including commuting accidents.
4 Including occupational diseases;.including non-fatal cases without lost workdays.
5 Including commuting accidents; persons losing more than three workdays
per period of disability.
6 Including non-fatal cases without lost workdays.
7 Including commuting accidents; including occupational diseases;
including non-fatal cases without lost workdays.
8 Including commuting accidents.
9 Employees only; excluding traffic accidents; year beginning April, 1993.
10 Including occupational diseases.
Sources: Country reports: Costa Rica 1994; Greece 1992, 1994; Mexico 1992, 1996; Singapore 1994, 1995; Thailand 1994, 1995; Euro-FIET Commerce Trade Section 1996; ILO 1994, 1995; Price Waterhouse 1991.

Operations, Hazards and Prevention

Cashiers

Many cashiers work at mechanized registers that require them to punch a keypad thousands of times per day to ring up the price of the article. The key punching is usually done with the right hand while products are moved from in front of the cashier to the rear of the cashier for packaging with the left hand. These work activities frequently involve poorly designed workstations, causing cashiers to lift heavy products, reach extensively for products and frequently twist the body in order to move products from one area to another. This job function places different burdens on each side of the body, causing lower-back pain, upper-extremity illnesses and repetitive-motion illnesses including tendinitis, carpal tunnel syndrome, tenosynovitis, thoracic outlet syndrome and hip, leg and foot problems.

Well-designed workstations, with automatic scanners, flexible work height conveyors, lowered bagging stations, extra personnel to bag the products and flexible seats (so that cashiers can sit to relieve lower-back and leg pressures) help eliminate upper- extremity pressures, strains and twisting motions.

Lasers

Bar-code readers and hand-held scanners in supermarkets are generally Class 2 lasers, which produce infrared radiation in the wavelength range of 760 to 1,400 nm; they are considered nonhazardous unless there is prolonged viewing of the laser beam. A laser produces a high-intensity light which can damage the retina of the eye. The eyes are vulnerable to heat, have no heat sensors and do not dissipate heat efficiently. Recommended safe practices should include, at a minimum, training workers about the hazards of looking into the beam of light and the damage to the eye that can result. Baseline eye examinations should be included in a worker protection programme to ensure that no damage has occurred.

Clerks

Retail clerks move large quantities of product from trucks to the loading dock and then to the shelves in the sales area of the store. Products come packaged in cartons of various weights. Manually unloading trucks and moving the product cartons to the front of the store may cause musculoskeletal problems. Pricing the items and placing them on the shelves puts tremendous pressure on the back, legs and neck. Using a pricing gun can cause carpal tunnel syndrome and other RSIs by putting excessive and repeated strain on the wrist, fingers and palm of the hand. Opening cartons with a knife or blade can lead to cuts on the hands, arms and other parts of the body. Cutting through cardboard with a dull knife requires extra pressure, which puts extra strain on the palms of the hands.

Mechanical lifting aids, such as fork-lift trucks, manual high-low trucks, dollies and carts help move items from one part of the store to another. Tables, scissor jacks and movable carts can help bring the items to a good height and help clerks place product on the shelves without back strain from lifting and twisting. Automated pricing guns or packaged goods already labelled will prevent wrist and upper extremity strains from repeated motions. Sharp knives will prevent forceful motions when opening cartons.

Meat cutters and delicatessen workers

Meat cutters and delicatessen workers work with saws, grinders, slicers and knives (see figure 1). When machine blades are not guarded, get jammed or become loose, fingers can be severed, cut, crushed or bruised. Machines must be securely anchored to the floor to prevent tipping and moving. Blades must be kept free of debris. If a machine is jammed, wooden devices should be used to unjam the machine with the power off. No machines should be unjammed with the power still on. Knives should be kept sharp to avoid problems in the wrists, hands and arms. The handles of knives, cleavers and clubs should be kept clean and unslippery.

Figure 1. Small-scale manual cutting of dried meet for local sale, Japan, 1989

OFR040F3

L. Manderson

When meat is mechanically weighed and packaged on a styrofoam tray in a plastic film sealed with a heating element, vapours and gases from the heated plastic may cause “meat wrapper’s asthma” and eye, nose and throat irritation, difficulty in breathing, chest pains, chills and fever. Local exhaust ventilation (LEV) should be placed near the heating element so that these vapours are not breathed in by workers, but are vented outside the workplace.

Meat cutters enter and leave freezers many times during the day. Work clothing should include heavy clothing for freezer work.

Floors and walkways can become slippery from meat, grease and water. Slips, trips and falls are common causes of injury. All waste material must be carefully discarded and kept off walking surfaces. Walking and standing mats must be cleaned daily or whenever they become soiled.

Chemical exposures

Retail workers are increasingly exposed to hazardous chemicals in cleaning products, pesticides, rodenticides, fungicides and preservatives. Hardware store workers, automotive distributive workers and others are potentially exposed to hazardous chemicals because of the stock of paints, solvents, acids, caustics and compressed gases. The hazardous or toxic chemicals vary depending on the nature of the products that are stocked in each establishment. These can include materials not necessarily considered hazardous. Department store workers, for example, can develop sensitivities and allergies to perfumes that are sprayed as demonstrations.

Cleaning products that are used to clean surfaces in supermarkets and other retail establishments may contain chlorine, ammonia, alcohols, caustics and organic solvents. These products may be used by cleaning crews during the night shift, in stores without natural ventilation and when the mechanical ventilation system is not working at full capacity. These chemical products affect the body when used in the workplace in industrial strengths and amounts. Chemical safety information must be readily available in the workplace for workers to read. Chemical containers must be labelled with the name of the chemical and how the product affects the body, as well as which protective equipment must be used to prevent illness. Workers need to be trained about the health hazards associated with the use of chemicals, how the chemicals enter the body and how to avoid exposure.

Retail workers who set up shop on the street are exposed to exhaust from motor vehicle traffic, as are the back-of-the-store workers who inhale exhaust from idling delivery trucks in the truck bays. The incomplete combustion products in motor vehicle exhaust include, among other things, carbon monoxide and polycyclic aromatic hydrocarbons. Exhaust gases and particulates affect the body is several ways. Carbon monoxide causes dizziness and nausea and acts as an asphyxiant, limiting the blood’s ability to use oxygen. Delivery trucks should turn off their engines while unloading. Mechanical general exhaust ventilation may be needed to vent the contaminated air away from workers. Routine scheduled maintenance and cleaning is needed to maintain the ventilation system.

Formaldehyde is frequently used on clothing and other textiles to prevent mildew. It can affect those who breathe it in. In stores with larger stocks of clothing and textiles without adequate natural or mechanical ventilation systems, formaldehyde gas can build up and irritate the eyes, nose and throat. Formaldehyde can cause skin and respiratory irritation and allergies and is considered a probable carcinogen.

Pesticides, rodenticides and fungicides are frequently used to keep vermin out of establishments. They can affect the nervous, respiratory and circulatory systems of human beings as well as insects, rodents and plants. It is important not to spray chemicals indiscriminately when people are present and to keep people away from sprayed areas until it is safe to enter them again. The pesticide applicator must be trained in safe work methods before pesticides are applied.

“Tight” buildings—those without windows that can open and without natural ventilation—are dependent on mechanical ventilation systems. These systems must provide an adequate exchange of air within the space and must include adequate fresh outdoor air. The air must be heated or cooled depending on the ambient temperature outside.

Sanitation

Personal hygiene is important in the retail industry, especially when employees handle food, money and hazardous chemicals. Toilets and washing and drinking facilities must be sanitary and available in areas where employees can use them while on duty. Facilities must have clean running water, soap and towels. Employees must be encouraged to wash their hands thoroughly after using the toilet and before returning to work. Clean, cool drinking water should be available throughout the work area. Good housekeeping is necessary to prevent vermin and accumulation of garbage. Trash should be picked up on a regular basis.

Sanitation facilities are difficult to maintain in open-air markets, but an attempt must be made to provide toilets and washing facilities.

Weather

In open-air markets, retail workers are exposed to the elements and subject to the problems relating to heat and cold. In supermarkets, cashiers often work at the front of the store close to the doors that the public uses to enter and exit, exposing cashiers to hot and cold air drafts. Air shields in front of the doors that go to the outside will help block drafts and keep the air temperature at the cash register consistent with the rest of the store.

Fire prevention

There are many fire hazards in retail stores, including locked or blocked exits, limited entry and exits, combustible and flammable materials and faulty or temporary electrical wiring and heating systems. If workers are required to fight a fire, they must be trained in how to call for help, use fire extinguishers and evacuate the space. Fire extinguishers must be of the appropriate type for the type of fire and must be inspected regularly and maintained. Fire drills are necessary so that workers know how to get out of the facility during an emergency.

Stress

A new trend in retail work, when the establishment is owned by a large conglomerate, is to change full-time work to part-time work. Many large retail stores are now staying open 24 hours per day, and many stay open every day of the year, forcing workers to work “unsocial” hours. Disruption of the internal biological clock which controls natural physical phenomena such as sleep, causes symptoms such as sleepiness, gastro-intestinal disturbances, headaches and depression. Changing shifts, working on holidays and part-time work cause emotional and physical stress on the job and at home. “Normal” family life is severely compromised and meaningful social life is restricted.

Late night hours are more and more prevalent, increasing the feeling of insecurity about personal safety and the fear of robberies and other types of violence on the job. In the United States, for example, homicide is a major cause of death on the job for women, with many of these deaths occurring during robberies. Handling money or working alone or during late night hours should be avoided. A regular review of security measures should be part of a violence prevention and security programme.

Part-time pay, with few or no benefits, increases job stress and forces many workers to find additional jobs in order to support their families and maintain health benefits.

 

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Tuesday, 15 March 2011 14:30

Telework

Telework—or working out of one’s home—is a growing trend in businesses internationally. This article discusses the occupational health and safety hazards of telework (from the Greek tele, meaning “far off”). The employer’s responsibility to provide safe and healthy working conditions to such employees will vary depending on the contract or understanding that exists between each teleworker and employer and on the applicable labour laws.

While telework is most widespread in the United States, where it involves over 8 million workers and accounts for 6.5% of the workforce, other countries also have significant numbers of teleworkers. There are more than 560,000 in the United Kingdom, 150,000 in Germany and 100,000 in Spain. There are over 32,000 in Ireland, which amount to 3.8% of the workforce (ILO 1997).

The growing trend toward telework arrangements can be explained by the following factors:

  • business efforts to reduce the time, expense and environmental impact of commuting
  • legislative efforts to reduce traffic-induced air pollution trends
  • changes in technology, computerization and electronic communication that enable businesses to employ workers in disparate geographic locations
  • costs of maintaining large office spaces needed to accommodate large numbers of employees
  • accommodation of workers who prefer telework due to physical disability, parenting needs or other family responsibilities or other reasons
  • a strategy to reduce absenteeism
  • recognition that workers have varying internal cycles of productivity and creativity.

 

Increased productivity is another factor, as a number of studies have demonstrated that telework can result in large productivity gains (ILO 1990b).

Telework may be contracted in several ways:

  • The employee works full time (or part time) at home for their employer and is entitled to all of the same benefits provided by that employer to all onsite workers.
  • The employee works full time for the employer but only works out of the home during a specified number of days per week or month.
  • The worker is defined as an independent contractor and does not receive benefits or equipment provided by the employer.

 

Health and Safety Hazards of Telework

The health and safety hazards of telework can include all of the same hazards found in conventional office environments, with several additional concerns.

Indoor air quality

Most homes are not equipped with mechanical ventilation systems. Instead, air exchanges in the home rely on natural ventilation. The effectiveness of this can depend on such factors as the type of insulation of the building and so on. Provision of a fresh supply of outside air cannot be guaranteed. If the natural ventilation is inadequate to remove sources of indoor air pollutants in the home work environment, then additional ventilation may be necessary.

Indoor air pollutants in the home environment may include the following:

  • natural gas or carbon monoxide exposure from inefficient heating systems or leaky stoves
  • vapours and gases from photocopiers, printers or other office machines
  • ongoing passive exposure to chemicals, gases or dusts resulting from renovation or construction in the worker’s home
  • exposure to the effluents of other activities if housed in a multi-use building (such as an apartment building with a nail salon, dry cleaner or fast food restaurant on the ground floor).
  • exposure to radon hazards if office is located in the basement in parts of the world where radon arises from construction materials or the earth.

 

Fire hazards

Home electrical wiring is rarely designed to accommodate the needs of the electrical equipment typically used in telework, such as printers, copiers and other office machines. Installing such equipment without assessing the wiring limits of the dwelling could create a fire hazard. Local building codes may prohibit the adjustments necessary to accommodate increased equipment needs.

Teleworkers who rent their apartments may live in multi-unit dwellings with inadequate fire evacuation plans, blocked means of egress to fire exits or locked exit doors.

Ergonomics hazards

Home work environments often rely on the employee’s personal furnishings such as chairs, tables, shelves and other items to perform required tasks. Computer workstations in the home environment may not allow for the adjustments necessary for computer-intensive work. A shortage of adequate surface area, shelf space or storage areas may result in excessive bending, awkward postures, excessive reaching and other risk factors for cumulative trauma disorders (CTDs). Working in cold or unevenly heated environments can also contribute to musculoskeletal injuries.

Lighting

Inadequate lighting may result in awkward body postures, eye strain and visual disturbances. Task lighting may be necessary for work surfaces or document holders. Wall and furniture surfaces should be neutral with a non-glare finish. While this glare-reducing strategy is increasingly utilized in office environments, it is not yet a standard of home decoration and design.

Occupational stress

Full-time employment in the home environment deprives the worker of the interpersonal and professional benefits of continuous interaction with co-workers, colleagues and mentors. The isolation created by telework can prevent the worker from engaging in professional development activities, taking advantage of promotional opportunities and contributing ideas to the organization. Gregarious workers in particular may depend on human contact and suffer personally and professionally without it. The lack of administrative support services for employees who require clerical assistance presents an additional burden to teleworkers. The employer should make an effort to incorporate the teleworker into staff meetings and other group activities, either in person or electronically (tele-conferencing) as per physical and geographical limitations.

Employees with children, disabled family members or ageing parents may perceive distinct advantages of working at home. But attending to the needs of dependent family members can affect the concentration needed to focus on job responsibilities. The ensuing stress can negatively impact on the worker who is unable to perform to capacity in the home and fails to meet employer expectations. Telework should not be considered as a substitute for child or elder care. Since workers vary tremendously in their capacity to balance work and other responsibilities in the home environment, the need for support services must be evaluated on a case-by-case basis to prevent excessive occupational stress and subsequent loss in productivity. No worker should be required to adopt a telework arrangement against his or her will.

Injury and Illness Compensation

Occupational illnesses often occur over long periods of time from cumulative exposures. Prevention of these illnesses depends on rapid identification of risk factors, fixing the problem using a variety of methods and medical management of the affected worker when the first signs or symptoms of illness appear.

To date, employer responsibility for accidents and injuries in the home environment have been debated on a case-by-case basis. Most national occupational health and safety standards do not include formal policies addressing the safety of teleworkers. The serious impact of this trend must be carefully evaluated and addressed via international standard-setting.

When telework arrangements shift the employee’s status to that of an independent contractor, the burden of many responsibilities shift to the employee as well. Once the work is performed in the home by an independent contractor, the employer no longer feels obligated to provide a healthy and safe workplace, access to preventive and curative medical care for the worker and his or her family, social security, disability insurance and compensation for injured workers who need to recuperate. This trend eliminates worker benefits and protections that were won after decades of struggle and negotiation.

Protection for the Teleworker

The contract between the teleworker and the employer must address the overall work environment, safety and health standards, training and equipment. Employers should inspect the home workspace (at agreed-upon times) to ensure worker safety and to identify and correct risk factors that could contribute to illness or injury. The inspection should evaluate indoor air, ergonomics, trip hazards, lighting, chemical exposure and other concerns. Clear policy must be established regarding the provision of office supplies required for job tasks. Liability issues must be clearly defined regarding employer (and worker) assets that are lost or damaged due to fire, natural disaster or theft. Employees must be exempt from financial liability unless found to be negligent.

In addition, telework arrangements should be evaluated on a regular basis in order to identify workers who discover that working at home does not work for them.

Summary

The advantages of telework are extensive, and beneficial telework arrangements should be encouraged for job tasks and mature workers who will have much to gain by working at home. Telework has enabled disabled workers to achieve greater independence and seek professional opportunities not previously offered or available. In return, employers are able to retain valuable workers. However, the telework arrangement must ensure continuation of employee benefits and occupational health and safety protections.

 

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Working in the Bank: Now Safer for the Personnel

What long-term measures can be taken to reduce the attraction of robbing a bank? The new provisions in Germany’s Accident Prevention Regulation (APR) for “Teller’s window” (VBG 120) significantly minimizes the risk to employees of being injured or killed in bank robberies.

A precise knowledge of the conduct of bank robbers is crucial. To this end, the Administration Trade Organization has been studying bank robberies since 1966. These studies have shown that, for example, bank robbers prefer small bank branches with few employees. Approximately one-third of bank robberies occur shortly after opening or just before closing. The goal is to leave the robbed bank as quickly as possible (after 2 or 3 minutes) and with the largest possible haul. Many bank robbers work under the wide-spread misconception that DM 100,000 and more can be taken from a teller’s window. The results of these and other studies are contained in the sections “Building and equipping” and “Operations” in the “Teller’s window” APR. Measures that drastically reduce the bank robbers’ expectations are proposed here to protect the employee. The success of these measures depends upon the employees strictly adhering to them in daily practice.

What basic requirements are set in the “Teller’s window” APR? In paragraph 7 of the “Teller’s window” APR, the central requirement is laid out: “Protecting the insured requires securing the banknotes so as to considerably reduce the incentive for robbery”.

What does that mean in daily practice? Easily accessible money should be kept and worked with in publicly accessible areas only within rooms separated from the public by bullet-proof or break-proof sections.

The maximum amount of accessible money allowed is given in paragraph 32: a combined maximum of DM 50,000 is allowed if there are bullet-proof tellers’ windows, other break-proof safeguards and at least 6 employees present. DM 10,000 may not be exceeded when using break-proof safeguards (but not bullet-proof tellers’ windows) in connection with containers equipped with time-staggered releases. There must be at least 2 employees present at all times, who must be in eye-contact.

To keep the incentive for bank robbery as low as possible, amounts of accessible money should be kept well below the maximums set in the “Teller’s window” APR. In addition, paragraph 25 calls for company instructions to set the maximum allowable accessible amounts for each branch. Larger amounts necessary for business and other needs should be secured in time-lock containers to make access by bank robbers more difficult.

Tellers’ windows that are not equipped with bullet-proof or break-proof safety guards and have no central money supply facility or employee-operated automatic teller machine should not have any accessible banknotes on hand.

Securing Windows and Doors

Personnel entrance and exit doors to teller areas containing cash must be secured against viewing or entering from outside, so that bank robbers cannot easily intercept employees entering and leaving bank rooms. The employee must be able to ensure, with built-in peepholes, that no danger exists.

To prevent unnoticed entrance by bank robbers into bank rooms, door closers must ensure that doors are always kept closed.

Since a considerable incentive for theft arises from viewing banknotes, windows behind which banknotes are handled must be secured against viewing or penetrating. Statistics show that holding strictly to this requirement results in very few bank robberies through windows or personnel entrances.

In contrast to personnel entrance and exit doors, doors for public traffic must have a clear view. Bank robbers can thereby be recognized early and an alarm sounded to bring assistance. Therefore it is important that the view not be obstructed by placards or the like.

Optimal Room Surveillance

In order to be able to identify the bank robber as quickly as possible, and to have effective evidence for court, optimal room surveillance equipment is prescribed in the “Teller’s window” APR. This is also important for determining whether the robber extorted money or threatened employees, since particularly brutal actions increase the penalty. Good pictures reduce the incentive to rob a bank.

The instruction “Installation directions for optimal room surveillance equipment (ORSE) SP 9.7/5” of July 1993 permitted only individual cameras as standard ORSE. Photographs are superior to video shots for identification because of greater detail recognition, resulting in better evidence. The disadvantage lies in the fact that photos are available only after the camera is triggered. Because of technical advances, the Administration technical committee now also permits the use of video cameras as possible ORSE. The corresponding instruction is now being prepared; it provides that the limited resolution of video pictures should be compensated for by using 2 views. For this, at least 2 cameras must be installed for recognizing the robber and for videotaping essential events.

Appropriate installation of the video technology can continuously record, and a “wanted” photo can thus be available without special triggering. The further advantages of the system include colour shots, quicker availability of “wanted” photos, transmission of the pictures to the police even during the robbery and the ability to constantly check the functioning of the camera.

Teller’s Window Security

The “Teller’s window” APR authorizes:

  • bullet-proof and break-proof glass enclosures and tellers’ booths
  • power-driven separations
  • break-proof separations in connection with bullet-proof screens
  • central money supply equipment
  • employee-operated teller machines.

Furthermore, customer-operated teller machines support the requirements of paragraph 7, since their use can reduce the amount of money in the booth or separated room.

In order to comply with the “Teller’s window” APR, the number of employees needed at the counter and the amounts to be taken in and paid out (quantity and number) must be known before a tellers’ counter is built or remodeled. Optimal security can be achieved only when counter security corresponds to the actual flow of business.

Constant Presence with Eye contact

Certain teller security measures require a minimum of 2 to 6 employees having eye contact with each other. This requirement flows from the recognition that bank robbers prefer smaller branches with higher yields, where the tellers, when threatened with a gun, cannot withdraw behind bullet-proof shielding.

Break-proof teller shielding can be used only when 6 employees with eye contact are always present in the counter area. This does not mean a 6-person location, where not everyone is always at their workplace due to vacation, sickness, customer visits and so on. Experience shows that this condition can be fulfilled only when 8 to 10 employees work at the location. Alternatively, a floater service can possibly be used to ensure the necessary minimum number of employees.

To guarantee the constant presence of 2 employees with eye contact, the location must have 3 to 4 positions.

It is important that the facility not be opened before the required minimum number of employees are present. When consultations are taking place in adjoining rooms, the minimum number of employees at the windows must still be maintained.

Security through Separation

Small branches

“Small branches” are those where the presence of at least 2 employees with eye contact in the counter area is not ensured. For these branches, bullet-proof shielding in connection with break-proof separations offers good protection, since the employee does not have to leave the secured area in the event of a robbery. Consultations are carried on in an area protected by break-proof shielding. Good communication is possible here. The bullet-proof shield, behind which the accessible cash must be kept, should be placed so that employees cannot be threatened with a weapon from the customer area. Money transactions take place by way of a prescribed hatch or sliding drawer. Since the employee must go into the bullet-proof-secured area in the event of an attack, the necessary personal security is provided. This area must not be left under any circumstances, including while handing money over to the robber.

Bullet-proof full separation presents an alternative for 1- to 3-person teller operations. It offers mechanical protection against the typical bank robbery, since all employees are separated from the robber by bullet-proof shielding. The disadvantage here is that communication with customers is reduced in the interest of security. So full bullet-proof separation is appropriate only for small branches.

Larger branches

The teller’s booth is a form of security in which only the teller’s work station is separated from the customer area. This possibility makes sense only for teller jobs in which the teller is fully occupied by his or her work in the booth and does not have to leave it.

Before installing a booth, it is necessary to determine whether the teller is fully occupied handling money. In smaller branches with only 2 to 4 employees, this is often not the case. If the teller has other tasks outside the booth, the security requirements of the APR are not met, since the teller is supposed to always be separated from the customers for protection against bodily attack. In practice what repeatedly happens is that while the teller is performing tasks outside the booth, the door is held open with a wedge or the key is left in the lock. Thus the security of the teller’s booth is compromised, which is of great interest to potential robbers.

The bullet-proof teller’s booth does hinder communication between the teller and customers. But since longer discussions take place in unsecured workplaces anyway, this does not present a big problem. More serious problems include ensuring draft-free ventilation and air-conditioning in small teller’s booths.

For power-driven separations, a movable steel wall, built into the counter, is raised in emergencies by way of several arranged triggers in second intervals. This creates a bullet-proof separation, with the employees behind it in a secure area. To prevent a robber from entering unnoticed, it must be activated whenever there are no employees in the vault area, or when work is being done that requires personnel to turn away from the counters. In order to avoid constant activation of the steel wall, this type of security should be used only in 2- to 4-person teller areas.

Furthermore, the tellers’ workstations can be isolated with bullet-proof separations. For this, full separations for all employees as well as tellers’ booths can be installed. This form of security, however, requires the constant presence of at least 6 employees with constant eye contact in the main hall.

Bullet-proof full separation and tellers’ booths can also be used when a minimum of 2 employees are present with eye contact and the accessible cash does not exceed DM 10,000. A time-release money container is required in this case so that the teller does not constantly have to leave the secured area to restock. Bank robbers avoid teller positions where they can expect only a small amount of cash or have to wait a long time for it. In this case, notice of the time-release container at the entrance and in the tellers’ area is important for the employees’ protection. This makes immediately clear to the potential robber that the employee has no control over the container and that only a small haul can be expected.

Security without Accessible Banknotes in the Main Hall

Security is possible even without building a separation between the employees and the customer area. But for this to reduce the incentive, no accessible quantities of money can be in the tellers’ area. Money taken in must be immediately secured. The money is kept in a cash box in an area not open to the public, so it cannot be threatened by the robber. The employees receive the necessary amounts of money through a tube delivery system in the main hall. Money taken in is sent to the cash box by this means. No minimum number of employees in the main hall is prescribed in this case. This type of security, however, results in longer waiting times for customers. The advantage is that bank robbers have virtually no chance of getting anything in a robbery.

Employee-operated automatic teller machines (ATMs) are a second way to make payments with cash that is not accessible in the main hall. These, referred to by the bank as AKT-designated machines, contain 4 to 6 magazines for holding banknotes in a time-released secured container. For payments, the required amount is called up using a keyboard, with which an alarm can also be sounded in emergencies. The money is delivered to the employee after a time delay. The length of the delay depends upon the amount of money and is set in paragraph 32 of the “Teller’s window” APR. These are set so that good service is possible, but the robber is scared off by the longer waiting times for larger amounts. Cash receipts should be secured by use of time- or double-closing containers.

At least 2 employees with eye contact must be constantly present when using an employee-operated ATM. For this reason, this form of security is appropriate only for locations in which 3 to 4 employees work. Discussions can take place in a conference room only when 2 or more employees are present in the customer area during the discussion.

In the case of a technical problem in an employee-operated ATM, appropriate instructions and measures should be prepared. These should include an emergency cash box and corresponding organizational procedures to ensure that work proceeds in accordance with the “Teller’s window” APR.

Company Directives and Instructions

The employer must prepare company directives for every teller’s window and regularly check on compliance. These directives should outline the possible events during a robbery and describe what to do during and after the robbery. Furthermore, daily instructions should be given, and use of the installed security equipment should be mandated. This is especially true when larger amounts of accessible banknotes are present. Instructions should also prescribe the manner of safekeeping for other valuable objects. Employees at the windows should be instructed in these company policies at least twice a year.

The purpose of these instructions is clear—to ensure that the employees follow the requirements of the “Teller’s window” APR for their own protection, and to significantly reduce the incentive for robbing a teller’s window.

 

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Tuesday, 15 March 2011 14:23

Offices: A Hazard Summary

Office workers may perform a wide variety of tasks, including: answering the telephone; interacting with the public; handling money; receiving and delivering mail; opening mail; typing and transcribing; operating office machinery (e.g., computers, adding machines, duplicating machines and so on); filing; lifting supplies, parcels and so on; and professional work such as writing, editing, accounting, research, interviewing and the like. Table 1 lists standard clerical jobs.

 


 

Table 1. Standard clerical jobs

Clerks

Secretaries and keyboard-operating clerks

Stenographers and typists
Word-processor and related operators
Data entry operators
Calculating-machine operators
Secretaries

Numerical clerks

Accounting and bookkeeping clerks
Statistical and finance clerks

Material-recording and transport clerks

Stock clerks
Production clerks
Transport clerks

Library, mail and related clerks

Library and filing clerks
Mail carriers and sorting clerks
Coding, proof-reading and related clerks
Scribes and related clerks
Other office clerks

Cashiers, tellers and related clerks

Cashiers and ticket clerks
Tellers and other counter clerks
Bookmakers and croupiers
Pawnbrokers and money-lenders
Debt-collectors and related workers

 

Client information clerks

Travel agency and related clerks
Receptionists and information clerks
Telephone and switchboard operators

Source: ILO 1990a.

 


 

Office workers are often thought to have pleasant, safe environments to work in. Even though office work is not as hazardous as many other workplaces, there are a variety of safety and health problems that may be present in an office. Some of these can pose significant risks to office workers.

Some Hazards and Health Problems

Slips, trips and falls are a common cause of office injuries. Poor weather conditions such as rain, snow and ice create slip hazards outside of buildings, and inside when wet floors are not cleaned up promptly. Electrical and telephone cords placed in aisles and walkways are a common cause of trips. Carpeted offices can create trip hazards when old, frayed and buckling carpet is not repaired and shoe heels catch on it. Electrical floor outlet boxes can cause trips when they are located in aisles and walkways.

Cuts and bruises are seen in office settings from a variety of causes. Paper cuts are common from file folders, envelopes and paper edges. Workers can be injured from walking into tables, doors or drawers that have been left open and are unseen. Office supplies and materials that are improperly stored can cause injury if they fall onto a worker or are placed where a worker would inadvertently walk into them. Cuts can also be caused by office equipment such as paper cutters and sharp edges of drawers, cabinets and tables.

Electrical hazards occur when electrical cords are placed across aisles and walkways, subjecting the cords to damage. Improper use of extension cords is often seen in offices, for example, when these cords are used in place of fixed (permanently installed) outlets, have too many items plugged into them (so that there could be an electrical overload) or are the wrong size (thin extension cords used to energize heavy-duty cords). Adapter or “cheater” plugs are used in many offices. Most often they are used to connect equipment that must be grounded (three-pronged plug) into two-pronged outlets without connecting the plug to ground. This creates an unsafe electrical connection. Ground pins are sometimes broken off a plug to allow for the same two-prong connection.

Stress is a significant psychosocial health problem for many offices. Stress is caused by many factors, including noise from overcrowding and equipment, poor relationships with supervisors and/or co-workers, increase in workload and lack of control of work.

Musculoskeletal problems and soft tissue injuries such as tendinitis result from office furniture and equipment which is not fitted to a worker’s individual physical needs. Tendinitis can occur from repeated movement of certain body parts, such as finger problems from constant writing, or filing and retrieving files from cabinets that are too full. Many office workers suffer from a variety of RSIs such as carpal tunnel syndrome, thoracic outlet syndrome and ulcer nerve damage because of the ill-fitting equipment and the lack of rest breaks from continuous keying (on a computer) or other repetitive activities. Poorly designed furniture and equipment also contribute to poor posture and nerve compression of lower extremities, since many office workers sit for long periods of time; all of these factors contribute to low-back and lower-extremity problems, as does constant standing.

Continual use of computers and poor overall lighting create eye strain for office workers. Because of this, many workers experience a worsening of vision, headaches, burning eyes and eye fatigue. Adjustments in lighting and computer screen contrast, as well as frequent breaks in eye focus, are necessary to help eliminate eye problems. Lighting must be appropriate for the task.

Fire and emergency procedures are essential in an office. Many offices lack adequate procedures for workers to exit a building in case of fire or other emergency. These procedures, or emergency plans, should be in writing and should be practised (through fire drills) so that office occupants are familiar with where to go and what to do. This insures that all workers will promptly and safely evacuate in the event of a real fire or other emergency. Fire safety is often compromised in offices by blocking of exits, lack of exit signage, storage of incompatible chemicals or combustible materials, inoperative alarm or firefighting systems or total lack of adequate means of notification of workers in emergencies.

Violence

Violence in the workplace is now being recognized as a significant workplace hazard. As discussed in the chapter Violence, in the United States, for example, homicide is the leading cause of death for women workers and the third-leading cause of death for all workers. Non-fatal assaults occur much more frequently than most people realize. Office workers who interact with the public—for example, cashiers—can be at greater risk of violence. Violence can also be internal (worker against worker). The vast majority of office workplace violence, however, comes from people coming to the office from the outside. Government office workers are much more at risk for workplace violence incidents because these workers administer laws and regulations to which many citizens have hostile reactions, be they verbal or physical. In the United States, 18% of the workforce are government workers, but they constitute 30% of the victims of workplace violence.

Offices can be made safer by restricting access to work areas, changing or creating policies and procedures which help eliminate sources of hostility and provide for emergency procedures and installing security equipment which is appropriate for the particular office being improved. Measures for improving safety are illustrated in the article describing German requirements for bank teller safety.

Indoor Air Quality

Poor indoor air quality (IAQ) is probably the most frequent safety and health complaint from office workers. The effect of poor IAQ on productivity, absenteeism and morale is substantial. The US Environmental Protection Agency (EPA) has listed poor IAQ in their top 5 public health problems of the 1990s. Many reasons exist for poor air quality. Among them are closed or sealed buildings with inadequate amounts of outside air, overcrowding of offices, inadequate maintenance of ventilation systems, presence of chemicals such as pesticides and cleaning compounds, water damage and mould growth, installation of cubicles and walls which block off air flow to work areas, too much or too little humidity and dirty work environments (or poor housekeeping).

Table 2 lists common indoor air pollutants found in many offices. Office machines are also a source of many indoor air pollutants. Unfortunately, most offices have not designed their ventilation systems to take into account emissions from office equipment.

Table 2. Indoor air pollutants that may be found in office buildings

Pollutant

Sources

Health effects

Ammonia

Blueprint machines, cleaning solutions

Respiratory system, eye and skin irritation

Asbestos

Insulation products, spackling compounds, fire retardants, ceiling and floor tiles

Pulmonary (lung) fibrosis, cancer

Carbon dioxide

Humans’ exhaled air, combustion

Headache, nausea, dizziness

Carbon monoxide

Automobile exhaust, tobacco smoke, combustion

Headache, weakness, dizziness, nausea; long-term exposure related to heart disease

Formaldehyde

Urea-formaldehyde foam insulation and urea-formaldehyde resin used to bind laminated wood products such as particleboard and plywood; tobacco smoke

Respiratory system, eye and skin irritation, nausea, headache, fatigue, possibility of cancer

Freons

Leaking air conditioning systems

Respiratory system irritation; heart arrhythmia at high concentrations

Methyl alcohol

Spirit duplicating machines

Respiratory system and skin irritation

Micro-organisms (viruses, bacteria, fungi)

Humidifying and air conditioning systems, evaporative condensers, cooling towers, mildewed papers, old books, damp newsprint

Respiratory infections, allergic responses

Motor vehicle exhaust (carbon monoxide, nitrogen oxides, lead particulates, sulphur oxides)

Parking garages, outside traffic

Respiratory system and eye irritation, headache (see carbon monoxide), genetic damage

Nitrogen oxides

Gas heaters and stoves, combustion, motor vehicle exhaust, tobacco smoke

Respiratory system and eye irritation

Ozone

Photocopying and other electrical machines

Respiratory system and eye irritation, headache, genetic damage

Paint vapours and dusts (organics, lead, mercury)

Freshly painted surfaces, old, cracking paint

Respiratory system and eye irritation; neurological, kidney and bone-marrow damage at high levels of exposure

PCBs (polychlorinated biphenyls), dioxin, dibenzofuran

Electrical transformers, old fluorescent light ballasts

Sperm and foetal defects, skin rashes, liver and kidney damage, cancer

Pesticides

Spraying of plants and premises

Depending on chemical components: liver damage, cancer, neurological damage, skin, respiratory system and eye irritation

Radon and decay products

Building construction materials such as concrete and stone; basements

Genetic damage, cancer, foetal and sperm damage, etc., due to ionizing radiation

Solvents (methylene chloride, 1,1,1-trichloro-ethane, perchloroethylene, hexane, heptane, ethyl alcohol, glycol ethers, xylene, etc.)

Typewriter cleaners and correction fluids, spray adhesives, rubber cement, stamp pad inks, felt-tip markers, printing press inks and cleaners

Depending upon solvent: skin, eye and respiratory system irritation; headaches, dizziness, nausea; liver and kidney damage

Sterilant gases (such as ethylene oxide)

Systems to sterilize humidifying and air-conditioning systems

Depending on chemical components: respiratory system and eye irritation, genetic damage, cancer

Tobacco smoke (passive exposure to particulates, carbon monoxide, formaldehyde, coal tars and nicotine)

Cigarettes, pipes, cigars

Respiratory system and eye irritation; may lead to diseases associated with smokers

Volatile organic compounds (VOCs)

Photocopiers and other office machines, carpets, new plastics

Respiratory system and eye irritation, allergic reactions

Source: Stellman and Henifin 1983.

The prevalence of poor IAQ has contributed to a rise in occupational asthma and other respiratory disorders, chemical sensitivity and allergies. Dry or irritated skin and eyes are also common health complaints that can be linked to poor IAQ. Action must be taken to investigate and correct problems that are causing poor IAQ according to air quality standards and recommendations.

Dermatitis (both allergic and irritant) can be caused by many of the air pollutants listed in table 2—for example, solvents, pesticide residues, inks, coated papers, typewriter ribbons, cleaners and so forth can cause skin problems. The best solutions for office workers are identification of the cause and substitution.

 

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Tuesday, 15 March 2011 14:19

Professionals and Managers

The workplace, especially in industrialized countries, has become increasingly a world of white-collar workers. For example, in the United States in 1994, white-collar work was done by 57.9% of the workforce, and service occupations accounted for 13.7% of the workforce. The professional occupations have moved from the fourth to the third largest occupational group (AFL-CIO 1995). Table 1  lists standard professional jobs according to the International Standard Classification of Occupations (ISCO-88). White-collar membership in national unions and organizations has grown from 24% in 1973 to 45% in 1993 (AFL-CIO 1995). Professional, managerial and technical occupational employment is expected to grow faster than average.


Table 1. Standard professional jobs

Professionals

Physicists, chemists and related professionals

Physicists and astronomers
Meteorologists
Chemists
Geologists and geophysicists

Mathematicians, statisticians and related professionals

Mathematicians and related professionals
Statisticians

Computing professionals

Computer systems designers and analysts
Computer programmers
Other computing professionals

Architects, engineers and related professionals

Architects, town and traffic planners
Civil engineers
Electrical engineers
Electronics and telecommunications engineers
Mechanical engineers
Chemical engineers
Mining engineers, metallurgists and related professionals
Cartographers and surveyors
Other architects and engineers

Life science and health professionals

Biologists, zoologists and related professionals
Pharmacologists, pathologists and related professionals
Agronomists and related professionals

Health professionals (except nursing)

Medical doctors
Dentists
Veterinarians
Pharmacists
Other health professionals

Nursing and midwifery professionals
College, university and higher education teaching professionals
Secondary education teaching professionals
Primary and pre-primary education teaching professionals
Special education teaching professionals
Other teaching professionals

Education methods specialists
School inspectors

Business professionals

Accountants
Personnel and career professionals
Other business professionals

Legal professionals

Lawyers
Judges
Other legal professionals

Archivists, librarians and related information professionals

Archivists and curators
Librarians and related professionals

Social science and related professionals

Economists
Sociologists, anthropologists and related professionals
Philosophers, historians and political scientists
Philologists, translators and interpreters
Psychologists
Social work professionals

Writers and creative or performing artists

Authors, journalists and other writers
Sculptors, painters and related artists
Composers, musicians and singers
Choreographers and dancers
Film, stage and related actors and directors

Religious professionals

Source: ILO 1990a.


One characteristic of professional office staff and managers is that their work function may require decision-making and responsibility for the work of others. Some managers or professional staff (for example, engineers, nurse administrators or social workers) may be located in industry and experience industrial hazards shared with the line staff. Others with managerial and executive functions work in buildings and offices remote from the industry itself. Both groups of administrative workers have risk from the hazards of office work: occupational stress, poor indoor air quality, chemical and biological agents, repetitive strain injuries (RSIs), fire safety concerns, sexual harassment and violence or assault in the workplace. See also the article “Offices: A hazard summary” in this chapter.

Demographic Changes

In a study of executive “hardiness” in the 1970s, not enough women could be found in executive positions to be included in the study (Maddi and Kobasa 1984). In the 1990s, women and minorities have had increasing representation in positions of authority, professional jobs and non-traditional jobs. However, a “glass ceiling” clusters most women in the lower levels of the organizational hierarchy: only 2% of senior management positions are held by women in the United States, for example.

As women enter traditionally male occupations, the question arises as to whether their experience in the workplace will result in an increase in coronary heart disease similar to that of men. In the past, women have been less reactive than men in stress hormone secretions when faced with the pressure to achieve. However, in studies of women in non-traditional roles (female engineering students, bus drivers and lawyers) a laboratory experiment showed that women had almost as sharp an increase in epinephrine secretion as men exposed to a difficult task, considerably higher than female clerical workers in traditional roles. A study of male and female managers in 1989 showed that both sexes had a heavy workload, time pressure, deadlines and responsibility for others. Women managers reported lack of communication at work and conflict between work and family as sources of stress, whereas male managers did not. Male managers reported the highest work satisfaction. The female managers were not found to have the support of a strong work network. Studies of professional women and their spouses showed child care responsibilities to be more heavily borne by women, with men shouldering chores with less time-specific demands, such as lawn care (Frankenhaeuser, Lundberg and Chesney 1991).

Although studies do not indicate that working leads to smoking, workplace stress is associated with increased smoking rates and difficulties in smoking cessation. In 1988, a higher rate of smoking was observed among female professionals as compared to male professional workers (Biener 1988). Smoking is a behavioural style of coping with stress. For example, nurses who smoked cigarettes reported higher levels of job stress than non-smoking nurses. In the Women and Health study, salaried workers were more likely to report job strain (45%) than hourly wage workers (31%), and more difficulty unwinding after work (57%) than hourly workers (35%) (Tagliacozzo and Vaughn 1982).

International changes have caused political and social restructuring that lead to large numbers of people emigrating from their country of birth. Workplace adaptation to minority groups results in more diverse workers represented in managerial positions. Implications of these changes include human factor analyses, personnel policies and diversity education. Ergonomic changes may be needed to accommodate diverse body types and sizes. Cultures may clash; for example, values regarding high productivity or time management may vary among nations. Sensitivity to such cultural differences is taught more often today as a global economy is envisioned (Marsella 1994).

New Structures of Work Organization

An increase in the use of participative techniques for input and governance of organizations, such as joint labour-management committees and quality improvement programmes, have changed the typical hierarchical structures of some organizations. As a result, role ambiguity and new skill requirements are frequently mentioned as stressors for those in managerial positions.

If the condition of managerial and supervisory work remains challenging, then the high stress/low illness individual can be described as a “hardy executive”. Such executives have been characterized as being committed to various parts of their lives (e.g., family, work, interpersonal relationships), as feeling a greater sense of control over what occurs in their lives and as regarding challenge in a positive mode. If stressful life events (e.g., staff reductions) can debilitate a worker, the model of hardiness provides a buffering or protective effect. For example, during periods of organizational change, efforts to maintain a feeling of control among workers could include increased clarity in work activities and job descriptions, and perceptions of the change as having possibilities, rather than as a loss (Maddi and Kobasa 1984).

Change in Workplace Technology

Work has altered so that in addition to the mental skills required of the professional, technological expertise is expected. The use of the computer, fax, telephone and video-conferencing, electronic mail, audio-visual presentations and other new technology has both changed the function of many managers and created ergonomic and other hazards associated with the machines which assist these functions. The term techno-stress has been coined to describe the impact of the introduction of new information technologies. In 1991 for the first time in history, US companies spent more on computing and communications hardware than on industrial, mining, farm and construction machines.

Computers affect how professional work and work processes are organized today. Such effects can include eye strain, headaches, and other VDU effects. The World Health Organization (WHO) in 1989 reported that psychological and sociological factors are at least as important as physical ergonomics in working with computers. Unintended consequences of computer use include the isolation of the computer operator, and the increase in working with computers in remote locations using high-speed modems. (See also the article “Telework” in this chapter.)

Occupational Stress

A well-known hazard is that of occupational stress, now linked to physiological outcomes, especially cardiovascular diseases. Stress is discussed extensively in several chapters in this Encyclopaedia.

A Swedish study of professional telecommunication engineers suggests that most studies of stress, which have usually been based on low- and medium-skill jobs, are not applicable to skilled professionals. In this study, three stress-reduction interventions were applied to the professional workforce with the following beneficial results: a feeling of being in control of one’s own work (thought to protect against high mental strain work); a lessening of mental strain; a lasting effect on social interactions and support; an improvement in elevated prolactin levels; a lessening of circulating thrombocytes (which may be a factor in stroke); and an improvement in cardiovascular risk indicators (Arnetz 1996).

As the human and financial costs of occupational stress have become known, many organizations have introduced initiatives that reduce stress and improve employee health in the workplace. Such interventions can focus on the individual (relaxation techniques and employee assistance programmes); on the individual-organizational interface (person-environment fit, participation and autonomy); or on the organization (organizational structures, training, selection and placement).

Violence

Managerial and professional workers are at risk for violence and assault because of their visibility and the possibility of adverse reactions to their decisions. Most commonly, violence and assault occur where money changes hands in retail settings or where troubled clients are seen. Workplaces at greatest risk for homicide (in descending order) are taxicab establishments, liquor stores, gas stations, detective services, justice and public order establishments, grocery stores, jewellery stores, hotels/motels, and eating/drinking places. Homicide in the workplace was the leading cause of occupational death for women, and the third leading cause of death for all workers in the United States from the mid-1980s to the mid-1990s (NIOSH 1993; Stout, Jenkins and Pizatella 1989).

Travel Hazards

Approximately 30 million people travelled from industrialized countries to developing countries in 1991, many of these business travellers. One-half of the travellers were US and Canadian residents, most commonly travelling to Mexico. European travellers were 40% of the total, with the majority visiting Africa and Asia. Health risks to international travellers occur when travelling to developing countries with high endemic rates of disease for which the traveller may have low levels of protective antibodies. An example is the hepatitis A virus (HAV), which is transmitted to 3 in 1,000 for the average traveller to developing countries and which increases to 20 in 1,000 people for those who travel to rural areas and were not careful with food and hygiene. Hepatitis A is a food- and water-borne disease. A vaccine is available that was introduced in Switzerland in 1992 and is recommended by the Advisory Committee on Immunization Practices for individuals travelling to areas with a high incidence of HAV (Perry 1996). Background and references for such hazards are provided elsewhere in this Encyclopaedia.

Other travel hazards include motor vehicle accidents (the highest rated cause of workplace fatality in the United States), jet lag due to diurnal disturbances, extended family absences, gastrointestinal disturbances, public transport accidents, crime, terrorism or violence. Traveller advisories for specific hazards are available from disease control agencies and embassies.

Health and Safety Interventions

Measure for the improvement of professional and managerial workers’ working conditions include the following:

  • All managerial, supervisory and professional workers should be included in health and safety training on the worksite.
  • Worksite smoking cessation programmes are appropriate as they are convenient, allow practice of cessation behaviours during working hours (when they are often most needed to cope with stressful events) and provide incentive to quit smoking.
  • Stress- and time-management programmes lead to improved worker satisfaction and productivity.
  • Diversity in the workplace will be commonplace in the coming century. Diversity training improves cross-cultural understanding.
  • Female professional and managerial staff need workplace support for their demanding roles at home and in the workplace: family leave, support groups and increased opportunities for advancement and control over their work.
  • Employee assistance programmes that are non-judgemental and confidential should be provided to all workers.
  • Computer work hazards require organizational, environmental, equipment and training emphasis, as well as engineering improvements in workstation, monitor and remote worksite designs.
  • Travellers need time to reorient to other time zones and countries, updated health information to protect them, time off to provide for family needs and security protections.
  • All workers need engineering, work practice and protective equipment controls to protect against violent acts and assaults by others. Training in personal and office protection should deal with prevention, personal protection, and post-assault help and counselling.

 

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Tuesday, 15 March 2011 14:16

The Nature of Office and Clerical Work

Work Organization and Stress

Office and sales work are traditionally thought of as clean, easy, safe work. While life-threatening, acute injuries are rare in these fields, occupational hazards exist that diminish the quality of life and in some cases, cause serious injury and death.

Stress can be defined as a physical or psychological stimulus that produces strain or disruption of the individual’s normal physiological equilibrium. Stress reactions include headaches, gastro-intestinal and sleep disturbances, high blood pressure and other cardiovascular disease, anxiety, depression and increased use of alcohol and drugs. Work in offices and retail trades is stressful both because of the structure of the industries and because of the organization of work.

The Structure of Work

Employers are increasingly using part-time and temporary workers (“temps” or contract workers). Often, this arrangement provides the desired flexibility in working hours. But there are costs. Government labour statistics show that the average part-time worker in the United States, for example, earns only 60% as much as a full-time worker on an hourly basis. Not only are they paid less, but their benefits, like health insurance, pensions, paid sick leave and vacation, are substantially less than those received by full-time workers. Fewer than 25% of part-time workers have employer-paid health insurance, compared to nearly 80% of full-time workers. Sixty per cent of full-time workers have pensions, while only 25% of part-time workers have this coverage. In 1990 in the US, there were nearly 5 million part-time workers who would have preferred to be employed full time. Other countries are also undergoing similar transformations of work. For example, in the European Union, 15% of the workforce and roughly 20% of clerical and sales worked had part-time jobs in 1991, and 8.4% of clerical workers were temps (De Grip, Hovenberg and Willems 1997).

In addition to lower pay and few benefits, there are other negative aspects of this restructuring of work. Temps often live with the stress of not knowing when they will be working. They also tend to work more overtime because they are often hired for “crunch” periods. Neither part-time workers nor temps receive equal protection under many government laws, including occupational safety and health regulations, unemployment insurance and pension regulations. Few are represented by labour unions. A case study commissioned by the US Occupational Safety and Health Administration of contract labour in the petrochemical industry shows that contract workers get less health and safety training and have higher injury rates than non-contract workers (Murphy and Hurrell 1995). The health consequences of an increasingly non-unionized, temporary workforce should not be underestimated.

Work organization

When the well-known long-term study of heart disease, the US Framingham Heart Study, examined the relationship between employment status and the incidence of coronary heart disease, it found that 21% of women clerical workers develop coronary heart disease, a rate almost twice that of non-clerical workers or housewives. According to Karasek’s demand control model of job stress, work that is characterized by high demands and low control, or decision-making latitude, is the most stressful, because of the imbalance between responsibility and ability to respond (Karasek 1979, 1990). Occupations such as clerical work, electronics manufacturing, garment work and poultry processing are characterized by tedium, ergonomic hazards and low job control. Clerical work ranked among the most stressful in this regard.

Recognizing the social, economic and physical determinants of health effects related to occupational stressors instead of focusing solely on personal pathology is a first step in the complete and long-term management of stress-related problems. While many people may benefit from programmes that provide individual coping and relaxation exercises, workplace stress management programmes should also acknowledge the broader social and economic constraints that provide the context for the daily lives of working people.

Air Quality

Many buildings have serious indoor air pollution problems. In offices, the combination of poor ventilation design, sealed buildings and the build-up of chemicals from building materials, office machines and cigarette smoke has resulted in an office smog in many buildings. Micro-organisms (e.g., moulds, bacteria) can flourish in the air-conditioning and humidifying systems, evaporative condensers and cooling towers in many office buildings. The result may be “tight building syndrome”, which can involve a wide range of symptoms depending on the situation, including allergies and respiratory infections, such as legionnaires’ disease, that sometimes can reach epidemic proportions. Perhaps the most common office air pollutant is cigarette smoke, which can increase the level of respirable particles in the air to 5 times that of a non-smoking office. Since research has linked the cigarette smoking of a spouse with the increased lung cancer risk of a non-smoking spouse, non-smoking office workers may also be at risk.

Ergonomic Hazards

Ergonomic hazards in the retail trade have risen in recent years as new technologies and organizational structures have been introduced. The trend in retail has been towards self-service operations and towards larger retail outlets. The introduction of the electronic scanner has created shorter cycle times and increased repetitiveness. In addition, the work space is often not adapted to the new technology, and many work practices can lead to musculoskeletal stress.

Many studies and investigations have found a higher rate of cumulative trauma disorders in cashiers than in non-cashiers, and a dose-response relationship between the work and these disorders. These jobs usually require high levels of upper extremity activity, and, as a result, carpal tunnel syndrome, tendinitis and tenosynovitis are experienced by a large proportion of cashiers. General merchandise clerks have been shown to have moderate levels of wrist activity and high levels of ankle activity. The check stand design can greatly influence the cashier’s posture and movement patterns, causing awkward positions, long reaches and frequent lifts. As a result other common areas of discomfort are the neck, shoulder, elbow and back. Prolonged standing for cashiers and clerks can also lead to back pain from the compressive forces associated with the activity. Additionally, prolonged standing may cause discomfort in the legs, knees and feet, and varicose veins. Further risk to the back comes from moving stacks which can be too heavy and/or too large.

There are many other sectors within the retail trades that experience these disorders as well as many more. For example, retail floristry and hairdressing are frequently associated with skin problems such as rashes and chronic dermatitis. The most common injuries in eating and drinking establishments are lacerations and burns. Take these factors into account along with the high turnover rate of employees and the inadequate training that can occur as a consequence, and the result is a setting that is conducive to chronic pain, discomfort and eventual cumulative trauma disorders.

Office Trades

The image of white-collar work being safe and clean is often deceptive. The dramatic change in workforce characteristics where job specialization, the repetitiveness of tasks and physical demands have all increased and available work space has decreased has led to many ergonomic injuries and illnesses. The most obvious injuries are associated with safety, such as falls on slippery floors, trips over electrical cords, collisions with open file cabinet drawers and moving heavy objects such as boxes of paper and furniture. However, with the ubiquitous use of computers in offices today, a new pattern of health problems exists. The areas of the body most frequently affected by cumulative trauma disorders are the upper limbs and neck. However, prolonged visual disply unit (VDU) use can lead to inflammation in the muscles, joints and tendons of the back and legs as well. Serious wrist disorders such as carpal tunnel syndrome, tendinitis and tenosynovitis are often associated with VDU use. These conditions can result from continuous wrist extension during keyboard use or from direct mechanical pressure on the wrist from such things as the sharp edge of the desk. Disorders of the fingers may result from the numerous, rapid fine finger movements that occur during typing. Shoulders being held in a static elevated position, resulting from too high a work surface, can possibly lead to tendinitis. As is often the case, prolonged sitting, which is characteristic of VDU use, can reduce the blood circulation and increase blood pooling in the legs and feet as the soft tissue in the legs is compressed. Lower-back pain is often a disorder associated with prolonged sitting, as the compressive forces in the spine can be elevated, especially if the chair is poorly designed. Other common health effects of VDU use are eye strain and headaches from improper lighting or VDU flicker. The computer is rarely the only piece of equipment in large offices. The noise level generated by the combination of copiers, typewriters, printers, phones and the ventilation system is often higher than the 45 to 55 dBA recommended for easy office and phone conservation and can interfere with concentration and elevate annoyance and stress levels, which have been associated with heart disease.

Environmental Hazards

The leading environmental hazards related to office and retail trades are primarily concerned with the consumer society: mall development and groundwater problems related to “green fields” development. In many suburban communities in advanced industrial nations, retail trade and office development in malls threatens the viability of both downtown urban areas and open space in the suburbs. In Asia and Africa the problems are different: along with the vast, unplanned growth of urban areas has come even sharper geographic division of social classes. But in the North and in the South, some cities have become dumping grounds for the poor and disenfranchised, as shopping centres and office complexes—and the more privileged classes—have abandoned urban areas. Neither the work of the future nor the consumption possibilities associated with it are available, and the urban environment has deteriorated accordingly. The new efforts of environmental justice organizations have sharpened the discussion of urban development, living, shopping and work.

The development of offices also presents the problem of wasteful uses of paper. Paper presents a problem of resource depletion (the cutting of forests for paper pulp) and the problem of solid waste. An international campaign against chlorine has also pointed out the chemical hazards associated with paper production. The recycling of paper, however, has captured the imagination of the environmentally conscious, and the paper and pulp industry has been induced to increase production of recycled paper products, as well as to find alternatives to the use of chlorine compounds. Electronic communication and record keeping may very well pose a long-term solution to this problem.

The enormous problem of excess packaging materials is a critical environmental concern. For example, Fresh Kills landfill, New York City’s dump for residential garbage, the largest landfill in the United States, covers about 3,000 acres and receives approximately 14,000 tons of trash a day. At present, in some places, the landfill reaches 150 feet (about 50 m) deep, but is projected to go to 450 feet (about 140 m) in 10 years. This does not include commercial or industrial non-toxic waste. Much of this waste is paper and plastic, which could be recycled. In Germany, producers of goods are required to take back packaging materials. Thus, companies are strongly encouraged to reduce their own wasteful retail marketing practices.

 

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The causes of the 1986 Chernobyl disaster have been variously attributed to the operating personnel, the plant management, the design of the reactor and the lack of adequate safety information in the Soviet nuclear industry. This article considers a number of design faults, operational shortcomings and human errors that combined in the accident. It examines the sequence of events leading up to the accident, design problems in the reactor and cooling rods, and the course of the accident itself. It considers the ergonomics aspects, and expresses the view that the main cause of the accident was inadequate user-machine interaction. Finally, it stresses the continuing inadequacies, and emphasizes that unless the ergonomics lessons are fully learned, a similar disaster could still occur.

The full story of the Chernobyl disaster is yet to be disclosed. To speak candidly, the truth is still veiled by self-serving reticence, half-truths, secrecy and even falsehood. A comprehensive study of the causes of the accident appears to be a very difficult task. The main problem faced by the investigator is the need to reconstruct the accident and the role of the human factors in it on the basis of the tiny bits of information that have been made available for study. The Chernobyl disaster is more than a severe technological accident, part of the reasons for the disaster also lie with the administration and the bureaucracy. However, the chief aim of this article is to consider the design faults, the operational shortcomings and the human errors that combined in the Chernobyl accident.

Who is to blame?

The chief designer for the pressure tube large power boiling water reactors (RBMK) used at the Chernobyl nuclear power plant (NPP), in 1989, presented his view on the causes of the Chernobyl accident. He attributed the disaster to the fact that the personnel failed to observe the correct procedures, or “production discipline”. He pointed out that the lawyers investigating the accident had arrived at the same conclusion. According to his view, “the fault lies with the personnel rather than some design or manufacturing failings.” The research supervisor for the RBMK development supported this view. The possibility of ergonomic inadequacy as a causative factor was not considered.

The operators themselves expressed a different opinion. The shift supervisor of the fourth unit, A.F. Akimov, when dying in a hospital as a result of receiving a dose of radiation of more than 1,500 rads (R) in a short period of time during the accident, kept telling his parents that his actions had been correct and he could not understand what had gone wrong. His persistence reflected absolute trust in a reactor that was supposedly completely safe. Akimov also said that he had nothing to blame his crew for. The operators were sure that their actions were in accord with regulations, and the latter did not mention the eventuality of an explosion at all. (Remarkably, the possibility of the reactor’s becoming dangerous under certain conditions was introduced into the safety regulations only after the Chernobyl accident.) However, in light of design problems revealed subsequently, it is significant that the operators could not understand why inserting rods into the core caused such a terrible explosion instead of instantly stopping the nuclear reaction as designed. In other words, in this case they acted correctly according to the maintenance instructions and to their mental model of the reactor system, but the design of the system failed to correspond to that model.

Six persons, representing only the plant management, were convicted, in view of the human losses, on the grounds of having violated safety regulations for potentially explosive facilities. The chairman presiding over the court said some words to the effect of proceeding with the investigations as regards “those who failed to take measures to improve the plant design”. He also mentioned the responsibility of department officials, local authorities and medical services. But, in fact, it was clear that the case was closed. Nobody else was held responsible for the greatest disaster in the history of nuclear technology.

However, it is necessary to investigate all causative factors that combined in the disaster to learn important lessons for safe future operation of NPPs.

Secrecy: The information monopoly in research and industry

The failure of the user-machine relationship that resulted in “Chernobyl-86” can be attributed in some measure to the policy of secrecy—the enforcement of an information monopoly—that governed technological communication in the Soviet nuclear energy establishment. A small group of scientists and researchers were given an exhaustive right to define the basic principles and procedures in nuclear power, a monopoly reliably protected by the policy of secrecy. As a result, reassurances by Soviet scientists as regards the absolute safety of NPPs remained unchallenged for 35 years, and secrecy veiled the incompetence of the civil nuclear leaders. Incidentally, it became known recently that this secrecy was extended to information relating to the Three Mile Island accident as well; the operating personnel of Soviet NPPs were not fully informed about this accident—only selected items of information, which did not contradict the official view on NPP safety, were made known. A report on the human engineering aspects of the Three Mile Island accident, presented by the author of this paper in 1985, was not distributed to those involved with safety and reliability of NPPs.

No Soviet nuclear accidents were ever made public except for the accidents at the Armenian and Chernobyl (1982) nuclear power plants, which were casually mentioned in the newspaper Pravda. By concealing the true state of affairs (thus failing to make use of lessons based on the accident analyses) the leaders of the nuclear power industry were setting it straight on the path to Chernobyl-86, a path that was further smoothed by the fact that a simplified idea of the operator activities had been implanted and the risk of operating NPPs was underestimated.

As a member of the State Expert Committee on the Consequences of the Chernobyl accident stated in 1990: “To err no more, we have to admit all our errors and analyse them. It is essential to determine which errors were due to our inexperience and which ones were actually a deliberate attempt to hide the truth.”

The Chernobyl Accident of 1986

Faulty planning of the test

On 25 April 1986, the fourth unit of the Chernobyl NPP (Chernobyl 4) was being prepared for routine maintenance. The plan was to shut the unit down and perform an experiment involving inoperative safety systems totally deprived of power from normal sources. This test should have been carried out before the initial Chernobyl 4 startup. However, the State Committee was in such a hurry to start up the unit that they decided to postpone indefinitely some “insignificant” tests. The Acceptance Certificate was signed at the end of 1982. Hence, the deputy chief engineer was acting according to the earlier plan, which presupposed a wholly inactive unit; his planning and timing of the test proceeded according to this implicit assumption. This test was in no way carried out on his own initiative.

The programme of the test was approved by the chief engineer. The power during the test was supposed to be generated from the rundown energy of the turbine rotor (during its inertia-induced rotation). When still rotating, the rotor provides electric power generation which could be used in an emergency. Total loss of power at a nuclear plant causes all mechanisms to stop, including the pumps which provide for the coolant circulation in the core, which in turn results in core meltdown—a grave accident. The above experiment was aimed at testing the possibility of using some other available means—the inertial rotation of the turbine—to produce power. It is not forbidden to perform such tests at operating plants provided that an adequate procedure has been developed and additional safety precautions have been worked out. The programme must ensure that a back-up power supply for the whole test period is provided. In other words, the loss of power is only implied but never actualized. The test may be performed only after the reactor is shut down, that is, when the “scram” button is pushed and the absorbing rods are inserted in the core. Prior to this, the reactor must be in a stable controlled condition with the reactivity margin specified in the operating procedure, with at least 28 to 30 absorbing rods inserted in the core.

The programme approved by the chief engineer of the Chernobyl plant satisfied none of the above requirements. Moreover, it called for the shutting off of the emergency core cooling system (ECCS), thus jeopardizing the safety of the plant for the whole test period (about four hours). When developing the programme, the initiators took into account the possibility of triggering the ECCS, an eventuality which would have prevented them from completing the rundown test. The bleed-off method was not specified in the programme since the turbine no longer needed steam. Clearly, the people involved were completely ignorant of reactor physics. The nuclear power leaders obviously included similarly unqualified people as well, which would account for the fact that when the above programme was submitted for approval to the responsible authorities in January 1986, it was never commented on by them in any way. The dulled feeling of danger also made its contribution. Owing to the policy of secrecy surrounding nuclear technology the opinion had formed that nuclear power plants were safe and reliable, and that their operation was accident-free. Lack of official response to the programme did not, however, alert the director of the Chernobyl plant to the possibility of danger. He decided to proceed with the test using the uncertified programme, even though it was not permitted.

Change in the test programme

While performing the test, the personnel violated the programme itself, thus creating further possibilities for an accident. The Chernobyl personnel committed six gross errors and violations. According to the programme the ECCS was made inoperative, this being one of the gravest and most fatal errors. The feedwater control valves had been cut off and locked beforehand so that it would be impossible even to open them manually. The emergency cooling was deliberately put out of action in order to prevent possible thermal shock resulting from cold water entering the hot core. This decision was based on the firm belief that the reactor would hold out. The “faith” in the reactor was strengthened by the comparatively trouble-free ten years’ operation of the plant. Even a serious warning, the partial core meltdown at the first Chernobyl unit in September 1982, was ignored.

According to the test programme the rotor rundown was to be carried out at a power level of 700 to 1000 MWth (megawatts of thermal power). Such a rundown should have been performed as the reactor was being shut down, but the other, disastrous, way was chosen: to proceed with the test with the reactor still operating. This was done to ensure the “purity” of the experiment.

In certain operating conditions, it becomes necessary to change or turn off a local control for clusters of absorbing rods. When turning off one of these local systems (the means of doing this are specified in the procedure for low-power operation), the senior reactor control engineer was slow to correct the imbalance in the control system. As a result, the power fell below 30 MWth which led to fission-product reactor poisoning (with xenon and iodine). In such an event, it is next to impossible to restore normal conditions without interrupting the test and waiting a day until the poisoning is overcome. The deputy chief engineer for operations did not want to interrupt the test and, by means of shouting at them, forced the control-room operators to begin raising the power level (which had been stabilized at 200 MWth). The reactor poisoning continued, but further power increase was impermissible owing to the small operating reactivity margin of only 30 rods for a large power pressure-tube reactor (RBMK). The reactor became practically uncontrollable and potentially explosive because, in trying to overcome the poisoning, the operators withdrew several rods needed to maintain the reactivity safety margin, thus making the scram system ineffective. Nevertheless, it was decided to proceed with the test. Operator behaviour was evidently motivated mainly by the desire to complete the test as soon as possible.

Problems due to the inadequate design of the reactor and absorbing rods

To give a better understanding of the causes of the accident, it is necessary to point out the major design deficiencies of the absorbing rods of the control and scram system. The core height is 7 m, while the absorbing length of the rods amounts to 5 m with 1 m hollow parts above and below it. The bottom ends of the absorbing rods, which go under the core when fully inserted, are filled with graphite. Given such a design, the control rods enter the core followed by one-metre hollow parts and, finally, come the absorbing parts.

At Chernobyl 4 , there were a total of 211 absorbing rods, 205 of which were fully withdrawn. Simultaneous reinsertion of so many rods initially results in reactivity overshoot (a peak in fission activity), since at first the graphite ends and hollow parts enter the core. In a stable controlled reactor such a burst is nothing to worry about, but in the event of a combination of adverse conditions, such an addition may prove fatal since it leads to prompt neutron reactor runaway. The immediate cause of initial reactivity growth was the initiation of water boiling in the core. This initial reactivity growth reflected one particular drawback: a positive steam void coefficient, which resulted from the core design. This design deficiency is one of the faults which caused operator errors.

Grave design faults in the reactor and the absorbing rods actually predetermined the Chernobyl accident. In 1975, after the accident at the Leningrad plant, and later on, specialists warned about the possibility of another accident in view of deficiencies in core design. Six months before the Chernobyl disaster, a safety inspector at the Kursk plant sent a letter to Moscow in which he pointed out to the chief researcher and chief designer certain design inadequacies of the reactor and the control and protection system rods. The State Supervising Committee for Nuclear Power, however, called his argument groundless.

The course of the accident itself

The course of the events was as follows. With the onset of the reactor coolant pump cavitation, which led to reduced flow rate in the core, the coolant boiled in the pressure tubes. Just then, the shift supervisor pushed the button of the scram system. In response, all the control rods (which had been withdrawn) and the scram rods dropped into the core. However, first to enter the core were the graphite and hollow ends of the rods, which cause reactivity growth; and they entered the core just at the beginning of intensive steam generation. The rise of the core temperature also produced the same effect. Thus there were combined three conditions unfavourable for the core. Immediate reactor runaway began. This was due primarily to gross design deficiencies of the RBMK. It should be recalled here that the ECCS had been made inoperative, locked and sealed.

The subsequent events are well known. The reactor was damaged. The major part of the fuel, graphite and other in-core components were blown out. Radiation levels in the vicinity of the damaged unit amounted to 1,000 to 15,000 R/h, although there were some more distant or sheltered areas where radiation levels were considerably lower.

At first the personnel failed to realize what had happened and just kept on saying, “It is impossible! Everything was done properly.”

Ergonomics considerations in connection with the Soviet report on the accident

The report presented by the Soviet delegation at the International Atomic Energy Association (IAEA) meeting in summer 1986 evidently gave truthful information on the Chernobyl explosion, but a doubt keeps on returning as to whether the emphasis was put in the right places and whether the design inadequacies were not treated much too gently. The report stated that the behaviour of the personnel was caused by the desire to complete the test as soon as possible. Judging from the facts that the personnel violated the procedure for preparing and carrying out tests, violated the test programme itself, and were careless when performing the reactor control, it would seem that the operators were not fully aware of the processes taking place in the reactor and had lost all feeling of danger. According to the report:

The reactor designers failed to provide safety systems designed to prevent an accident in the case of deliberate shut-off of the engineered safety means combined with violations of the operating procedures since they regarded such a combination as unlikely. Hence the initial cause of the accident was a very unlikely violation of the operating procedure and conditions by the plant personnel.

It has become known that in the initial text of the report the words “plant personnel” were followed by the phrase “which showed the design faults of the reactor and the control and protection system rods”.

The designers considered the interference of “clever fools” in plant control unlikely, and therefore failed to develop the corresponding engineered safety mechanisms. Given the phrase in the report stating that the designers considered the actual combination of events unlikely, some questions arise: Had the designers considered all possible situations associated with human activity at the plant? If the answer is positive, then how were they taken into account in the plant design? Unfortunately, the answer to the first question is negative, leaving areas of user-machine interaction undetermined. As a result, onsite emergency training and theoretical and practical training were carried out mainly within a primitive control algorithm.

Ergonomics was not used when designing computer-assisted control systems and control rooms for nuclear plants. As a particularly serious example, an essential parameter indicative of the core state, that is, the number of the control and protection system rods in the core, was displayed on the control board of Chernobyl 4 in a manner inappropriate for perception and comprehension. This inadequacy was overcome only by operator experience in interpreting displays.

Project miscalculations and ignoring human factors had created a delayed-action bomb. It should be emphasized that the design fault of the core and the control system served as a fatal basis for further erroneous actions by operators, and thus the main cause of the accident was the inadequate design of user-machine interaction. Investigators of the disaster called for “respect to human engineering and man-machine interaction, it being the lesson Chernobyl taught us.” Unfortunately, it is difficult to abandon old approaches and stereotyped thinking.

As early as 1976, academician P.L. Kapitza seemed to foresee a disaster for reasons that might have been relevant to preventing a Chernobyl, but his concerns were made known only in 1989. In February 1976, US News and World Report, a weekly news magazine, published a report on the fire at the Browns Ferry nuclear facility in California. Kapitza was so concerned about this accident that he mentioned it in his own report, “Global problems and energy”, delivered in Stockholm in May 1976. Kapitza said in particular:

The accident highlighted the inadequacy of the mathematical methods used to calculate the probability of such events, since these methods do not take into account the probability due to human errors. To solve this problem, it is necessary to take measures to prevent any nuclear accident from taking on a disastrous course.

Kapitza tried to publish his paper in the magazine Nauka i Zhizn (Science and Life), but the paper was rejected on the grounds that it was not advisable “to frighten the public”. The Swedish magazine Ambio had asked Kapitza for his paper but in the long run did not publish it either.

The Academy of Sciences assured Kapitza that there could be no such accidents in the USSR and as an ultimate “proof” gave him the just published Safety Rules for NPPs. These rules contained, for example, such items as “8.1. The actions of the personnel in case of a nuclear accident are determined by the procedure for dealing with the consequences of the accident”!

After Chernobyl

As a direct or indirect consequence of the Chernobyl accident, measures are being developed and put into effect to ensure safe operation of current NPPs and to improve the design and construction of future ones. In particular, measures have been taken to make the scram system more fast-operating and to exclude any possibility of its being deliberately shut off by the personnel. The design of the absorbing rods has been modified and they have been made more numerous.

Furthermore, the pre-Chernobyl procedure for abnormal conditions instructed operators to keep the reactor operating, while according to the current one the reactor must be shut down. New reactors that, basically speaking, are in fact inherently safe are being developed. There have appeared new areas of research which were either ignored or non-existent before Chernobyl, including probabilistic safety analysis and experimental safety bench tests.

However, according to the former USSR Minister of Nuclear Power and Industry, V. Konovalov, the number of failures, shutdowns and incidents at nuclear power plants is still high. Studies show that this is due mainly to the poor quality of the delivered components, to human error and to inadequate solutions by design and engineering bodies. The quality of construction and installation work leaves much to be desired as well.

Various modifications and design changes have become common practice. As a result, and in combination with inadequate training, qualifications of the operating personnel are low. The personnel have to improve their knowledge and skills in the course of their work, based on their experience in plant operation.

Ergonomics lessons are still to be learned

Even the most effective, sophisticated safety control system will fail to provide for plant reliability if human factors are not taken into account. Work is being prepared for the vocational training of personnel in the All-Union Scientific and Research Institute of NPPs, and there are plans to considerably enlarge this effort. It should be admitted, however, that human engineering still is not an integral part of plant design, construction, testing and operation.

The former USSR Ministry of Nuclear Power replied in 1988 to an official inquiry that in the period 1990-2000 there was no need for specialists in human engineering with secondary and higher education as there were no corresponding requests for such personnel from nuclear plants and enterprises.

To solve many of the problems mentioned in this article it is necessary to carry out combined research and development involving physicists, designers, industrial engineers, operating personnel, specialists in human engineering, psychology and other fields. Organizing such joint work entails great difficulties, one particular difficulty being the remaining monopoly of some scientists and groups of scientists on “truth” in the field of nuclear energy and the monopoly of the operating personnel on the information concerning NPP operation. Without available comprehensive information, it is impossible to give a human engineering diagnosis of a NPP and, if necessary, propose ways to eliminate its shortcomings as well as to develop a system of measures to prevent accidents.

In the NPPs of the former Soviet Union the current means for diagnosis, control and computerization are far from accepted international standards; plant control methods are needlessly complicated and confusing; there are no advanced programmes of personnel training; there is poor support of plant operation by designers and highly outdated formats for operating manuals.

Conclusions

In September 1990, after further investigations, two former Chernobyl employees were freed from prison before the end of their terms. Some time later all the imprisoned operating personnel were freed before the appointed time. Many people involved with the reliability and safety of NPPs now believe that the personnel had acted correctly, even though these correct actions resulted in the explosion. The Chernobyl personnel cannot be held responsible for the unexpected magnitude of the accident.

In an attempt to identify those who were responsible for the disaster, the court mainly relied on the opinion of technical specialists who, in this case, were the designers of Chernobyl nuclear power plant. As a result of this one more important Chernobyl lesson is learned: As long as the main legal document that is used to identify responsibility for disasters at such complicated establishments as NPP is something like maintenance instructions produced and changed exclusively by designers of these establishments, it is too technically difficult to find the real reasons for disasters, as well as to take all the necessary precautions to avoid them.

Further, a question still remains as to whether operating personnel should strictly follow the maintenance instructions in the case of disaster or whether they should act according to their knowledge, experience or intuition, which may even contradict the instructions or be unconsciously associated with the threat of severe punishment.

We must state, regrettably, that the question “Who is guilty of the Chernobyl accident?” has not been cleared up. Those responsible should be sought among politicians, physicists, administrators and operators, as well as among development engineers. Convicting mere “switchmen” as in the Chernobyl case, or having clergymen sanctify NPPs with holy water, such as was done with the incident-plagued unit in Smolensk in 1991, cannot be the correct measures to ensure safe and reliable operation of NPPs.

Those considering the Chernobyl disaster merely an unfortunate nuisance of a sort which will never happen again, have to realize that one basic human characteristic is that people do make mistakes—not only operating personnel but also scientists and engineers. Ignoring ergonomic principles about user-machine interactions in any technical or industrial field will result in more frequent and more severe errors.

It is therefore necessary to design technical facilities such as NPPs in such a way that possible errors are discovered before a severe accident can happen. Many ergonomic principles have been derived trying to prevent errors in the first place, for instance in the design of indicators and controls. However, still today these principles are violated in many technical facilities all over the world.

The operating personnel of complex facilities need to be highly qualified, not only for the routine operations but also in the procedures necessary in the case of a deviation from normal status. A sound understanding of the physics and the technologies involved will help the personnel to react better under critical conditions. Such qualifications can only be attained through intensive training.

The constant improvements of user-machine interfaces in all kinds of technical applications, often as a result of minor or major accidents, show that the problem of human errors and thus of user-machine interaction is far from being solved. Continuous ergonomic research and the consequent application of the obtained results aimed at making user-machine interaction more reliable is necessary, especially with technologies that bear a highly destructive power, such as nuclear power. Chernobyl is a severe warning of what can happen if people—scientists and engineers, as well as administrators and politicians—disregard the necessity of including ergonomics in the process of designing and operating complex technical facilities.

Hans Blix, Director General of the IAEA, has stressed this problem with an important comparison. It has been said that the problem of war is much too serious to be left solely to generals. Blix added “that the problems of nuclear power are much too serious to leave them solely to nuclear experts”.

 

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Contents

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