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Causes of stress (stressors)

Much has been written about the stress rating (known as the Homes-Rahe life stress inventory) assigned to certain life events, ranging from the death of a child or partner which produces the highest stress levels, to changes in social activities which rate lowest on the scale. Whilst acknowledging the impact of factors outside work on overall stress levels, it is the intention of this section to focus principally on occupational causes.

The following work factors are all known to contribute to stress:

Physical conditions

noise poor lighting overcrowding extremes of temperature toxic fumes and chemicals badly designed furniture poor maintenance dangerous equipment working with VDUs

Balancing the demands of home and work

poor childcare facilities long hours need to take time off to care for sick children and other dependents

Job design

work overload machine-paced work surveillance and monitoring by computers, videos and listening devices repetitive work time pressures responsibility for lives uncertain responsibilities excessive requirements introduction of new technology underuse of skills

Relationships in organisation

unsympathetic management lack of support, assistance or training harassment (sexism, racism, homophobia, ageism) customer/client complaints poor communication social isolation at work

Work organisation and conditions

low pay lone working lack of job security shiftwork nightwork lack of control over work continuous changes in work organisation lack of participation in decision-making financial constraints rigid hierarchy harsh disciplinary procedures inadequate staffing overpromotion underpromotion

'Psychosocial factors' is the academic term used to describe all the non-physical characteristics of work structures and organisation which can affect physical as well as mental health directly or indirectly through the experience of stress.

In the next section we look at some aspects of work organisation which are most likely to contribute to stress.

Excessive working hours

Sudden death is the most extreme consequence of working excessive hours. Physical and psychological fatigue is common. There is an increased risk of heart disease, and victims suffer from sleep difficulties, sexual disorders, gastric disturbances, headaches, backaches, dizziness and weight loss. Accidents become more frequent. There is a range of psychological and behavioural problems: apathy, depression, disorganisation, feelings of incapability, irritability, intolerance, boredom and cynicism. Burnout, defined as exhaustion, underachievement and the inability to handle personal relationships, can result. In the later stages signs of mental illness can appear. All these effects have knock-on consequences for family and social life (Alfredson et al 1993; Karaki 1991).

Body clocking

The human body works according to circadian rhythms, i.e. body temperature, hormone levels and a variety of other bodily functions vary in an approximately 24 hour cycle. Human performance varies at different times and is lowest at night time. There is also a dip in early afternoon. There is a biological clock which regulates the cycle and which can function to some degree independently of environmental stimuli. The most important environmental stimulus which does have an effect is the light/dark cycle. This basically enables human being to function according to the changing times of days and seasons. Knowledge of the time of day and the daily experience of family and social life also help to synchronise the biological and environmental cycles. It has been shown for night workers that there is only partial adjustment of the circadian rhythms (Zenz 1988).

Nightwork

There are established health effects of night work, fatigue and sleep loss, appetite disturbance, gastrointestinal complaints, heart disease and mood, personality and neurological disorders. There is evidence of menstrual effects and adverse pregnancy outcome in woman. There is an increased risk of accidents. There is increased stress on all variations of personal and social life, including relationship breakdown and increased alcohol and drug dependency. Despite all these established health effects, a quarter of British employees work nights, either permanently or as part of a rotating shift pattern (The Safety and Health Practitioner 1992).

Sleep difficulties are a major problem for night workers, affecting both the duration and quality of sleep. Day sleep after night work is generally of shorter duration than normal night sleep and more prone to interruption. It has also been shown to be of poorer quality. After a period of night work/day sleep, a sleep deficit can accumulate leading to fatigue. There is some evidence this effect of night work is more severe in older workers (AAOHN Journal 1991).

About half of night workers complain of loss of appetite, resulting both from the non-availability of suitable of suitable food and the requirement to eat at unusual times. This can lead to indigestion and ulcers. Typically the incidence of ulcers increases after about five years exposure to variable work schedules. A recent study estimated that between 30 and 50 per cent of shiftworkers suffer from gastrointestinal disturbances, a proportion some 5-10 higher than in day workers (Health and Safety Information Bulletin April 1994).

Though it is a matter of dispute, evidence is now accumulating that night work does lead to an increase in heart disease (Rosa and Colligan 1992). Groups as diverse as agricultural workers and airline pilots have shown an increased propensity to coronary artery disease and heart attacks after five to ten years on nights. Night work has been correlated with increased cholesterol levels, a finding also borne out by animal studies.

Accident rates, both at work and travelling to and from work, are affected by sleepiness and napping. The particular danger period is late on in shifts shortly after a transition from day to night work. This is when the body has had the least opportunity to adjust its ordinary rhythm. This effect has been demonstrated over a wide range of occupations (Gold et al 1992). It has been pointed out that many disasters occur on the night shift; Three Mile Island, Chernobyl, Bhopal and Exxon Valdez are quoted as examples.

A study of the work schedules of women suffering spontaneous abortions or fetal death showed that women working evening or night shifts were three to four time more likely to suffer pregnancy loss that women working day shifts (Infante-Rivard et al 1993). The authors allowed for all other factors and concluded that pregnancy loss should be considered an additional hazard of evening and night work. The European Union Directive on pregnant workers will generate new rights on night work. Pregnant women and new mothers who obtain a medical certificate stating that it is necessary for their safety or health will have the right to transfer to suitable day work or go on paid leave. At the time of writing, it remains to be seen how the Health and Safety Commission will translate the Directive into UK Regulations, but the proposals put out for consultation leave something to be desired.

The new European legislation follows in part the recommendations of the International Labour Office which adopted a detailed set of proposals at a conference in 1990 (see Part 3).

Shiftwork

All the health effects of night work are compounded by rotating shift arrangements. On permanent nights, the biological clock can adapt to a degree but with variable shifts, this is less possible. Thus, all the stresses resulting from disruption of the circadian rhythms are increased by the constant alteration of working hours.

The Health and Safety Executive has produced two major reviews of the health effects of shiftwork. (Harrington 1978; Waterhouse 1990). Harrington in particular was highly critical of many reports of adverse health effects of shiftwork, dismissing many of them on methodological grounds. He denied that there was a link between shiftwork and heart disease or neurological problems. He was of the opinion that repetitive tasks associated with low motivation and fatigue were performed less well at night but that interesting jobs were less affected. He also rejected any clear relationship between the time of day and the frequency of accidents. The later report does modify the position on cardiovascular illness and neurological problems but still takes an ambivalent attitude to the link between accidents and shiftwork. Much discussion goes into the differences among individuals in the effect of shiftwork and there is a list of the medical factors which should be taken into account in counselling workers against shiftwork:

those with gastric or duodenal ulcers those with recurrent problems of indigestion and related disorders those on chronic medication in which the timing is important - insulin-dependent diabetics and those with severe thyroid or adrenal pathologies would fall into this category those with severe neurological problems, particularly depressives who might be adversely by altered light/dark schedules those with chronic heart disorders those with chronic sleep disorders epileptics, as treatment is hampered by irregular sleep-wake schedules and sleep deficit can increase the tendency to seizures

A number of other factors are also explored including age, physiology, personality and social effects. One of Harrington's observations has been widely quoted elsewhere. This is that 10 per cent of shiftworkers enjoy shiftwork, most put up with it and 20-30 per cent find it unpleasant enough to leave. In a paper which prides itself on its scientific rigour, it is somewhat surprising to find that this assertion is based only on a personal communication and not on published research. The trade union COHSE (now part of UNISON) put it rather differently: "10 per cent of shiftworkers enjoy night work and this means that 90 per cent have to put up with night work unwillingly or are forced to leave due to ill health" (COHSE 1992). At any rate it can be surmised that workers put up with shiftwork because the alternatives on offer are low pay and unemployment.

A huge amount of research has focused on the differences among individuals as a means of establishing the best means of adapting to or coping with shiftwork. This places the emphasis on the individual modifying his/her lifestyle to suit the demands of the job. One questionable approach advocates personality "hardiness" training (Wedderburn 1994). Wedderburn reports that training in commitment to the job and acceptance of change can reconcile workers to shiftwork and reduce the incidence of digestive problems. He also reports that employees often resist educative attempts to change their habits. Well, yes.

A comprehensive set of recommendations for adapting the worker to the job can be found in a 1991 report by a Dublin-based research organisation (European Foundation for the Improvement of Living and Working Conditions 1991). This contains advice on handling sleep problems, eating, physical fitness and keeping up social contacts. There are no less than 36 hints on avoiding sleep deprivation. Some of these verge on the comical, e.g., "Have you thought of rotating your bedroom?" This turns out to mean finding the quietest place to sleep in your home in the day time. Other advice is to move to a quieter part of town. Evidently, mansions for shiftworkers is the answer.

However well meaning all of this is, it indicates the upheaval required to mitigate the effects of shiftwork. All the recommendations on diet and exercise are impeccable and add up to a guide to a healthy lifestyle. They also require quite a substantial disposable income. This is equally the case for the suggestions on maintaining social contacts which make important points on the role of trade unions. Shiftworkers are advised to insist on special meetings with trade union officers at times which suit everyone, to have a representative available for workers on all shifts, and to ensure that some shiftworkers become union representatives.

A great deal of research has also been carried out on adapting the job to the worker, i.e. investigating shiftwork patterns to establish those which have the least effect on health. A very wide range of shift patterns have been developed:

treble shift non-continuous - three consecutive shifts per day providing 24 hour cover, five days per week; rotation of shifts, e.g. changing shift each week with a three-week cycle alternating days and nights - two shifts per day operating five days per week; workers employed alternately with one week on days, one week on nights double days - two shifts per day - one in morning, one in afternoon, no night work; workers alternate between shifts permanent nights - night shift for four or five nights per week evening or twilight shift - part-time shift in late afternoon or evening mini-shifts - two or three rotating or overlapping shifts of about five hours each, normally operating during the daytime rotating days - six or seven days cover per week with workers working five days per week weekend shifts - workers work Saturday and Sunday only, as an addition to double day or treble shiftworking carried out by other workers during the week split shifts - workers have two or more periods of work per day separated by long break of two hours or more eight hour continuous - three eight-hour shifts per day with workers working on each shift with various types of rotation 12 hour continuous - two 12 hour shifts per day with workers working on each shift with a variety of rotas.

Recommendations on constructing shift patterns that have minimal effect are detailed in Part 3.

There is a consensus on permanent nights; circadian rhythms adjust completely for only a few people and people on permanent nights do become socially isolated (that small proportion of workers who claim to like night work are reported to find this the attraction). Sleep deficit builds up with a succession of nights and there is some evidence that the probability of accidents increases after two night shifts. Quickly rotating patterns offer more stability in social contacts than weekly rotated shifts or permanent nights. The earlier a morning shift starts, the more likely is a reduction of sleep time in order to wake, rise and travel. Though shift change times are often regarded as rigid, flexible changeover times can be introduced even for three-shift systems and this can give individuals more scope for sleeping arrangements and social contacts.

The main arguments against short intervals between shifts are the practical ones of not being able to fit in essential non-work activities, especially sleep. Such arrangements sometimes seem attractive as a way of packing in a lot of work time quickly in order to create bigger blocks of time off. They are however known to produce high levels of fatigue. The argument about dead time between work periods also applies to split shifts. Compressed working weeks, i.e. long periods of continuous work followed by extended time off, are attractive not so much for leisure activities but for the opportunity to do a second job. Young workers with high financial needs are more likely to be tempted by such arrangements but older workers (i.e. those who survive) attest to their exhausting nature.

There are contradictory reports on the effect of the length of shifts. Rapidly rotating 12 hour shifts have been recommended and there have been suggestions that the incidence of adverse health effects for 12 hours is no greater than for eight hour shifts. There are plenty of reports of microsleep, napping and human error beginning to rise six hours into shifts, resulting in increased accident rates. Accidents by truck and bus drivers are particularly notable in this respect. Two views are advanced on the relative length of night versus day shifts. On the one hand, it is argued that where the effort involved in the job is roughly the same at all times, the night shift should be relatively shorter in view of the extra strain in maintaining the same level of performance. For example, the night shift could be seven hours and the other two 8.5 hours. On the other hand, where the night work is lighter than that during the day, a longer night shift may be a possibility. There are a number of issues which are so far unresolved and this is one area where the health and safety arguments do not indicate the best practice.

It is argued that circadian rhythms adjust better to forward rotating shifts than to backward ones. Workers on forward rotating schedules report greater alertness and less fatigue than those on backwards cycles. It also seems that there is more napping on the job in backwards cycles. There do not appear to be reports supporting the contrary point of view. In distinction to the view above some opinion favours slowly rather than rapidly rotating shifts, the former providing more time to adjust to the change in arrangements. This is another area where research is incomplete and where workers should ensure that their own needs and experience are paramount.

A number of unions (COHSE, GMB) have advised their members of the effects of shift and night work and the TUC has now taken it up as a campaign issue. A number of motions were carried at the 1993 Congress on the relationship between working hours and stress and instructing the General Council to identify and publicise best practice in the prevention and alleviation of work related stress. However it has to be confessed that trade union practice does not always measure up to the demands of the situation. A GMB member wrote in to his union journal to complain that shiftwork was ruining plans to start a family (GMB Journal May 1994). He and his wife had been put on separate shifts and had now started quarrelling whenever they managed to spend time together. Moreover his sex drive seemed to have gone. However, the advice he got in return was less than adequate - "Many couples working shifts will know exactly how helpless you are feeling. Pressures of work can often play havoc with our privates lives. But the important thing to remember is that no-one is to blame and there are solutions to your problem." The solutions, apart from the partners getting together on the same shift, purely consisted in adjustments to their personal life, including putting their family plans on hold. The poor member was assured that "these simple measures" really would work. No suggestion here that you could blame the bosses, question whether the shiftwork was really necessary in the first place or take collective industrial or political action to improve things. Yet it might be suggested that it is only in these ways that real changes can be effected.

Violence as a source of stress

A recent survey of union representatives covering 90,000 workers in local government, the civil service, passenger transport services, postal services, education, the health service, the probation service, the retail industry and banking and finance found that over 70 per cent of the workplaces had experienced violent incidents in the last two years (Bargaining Report May 1994). These incidents included verbal abuse, threats and actual physical assault.

Workers who routinely experience violence at work, the threat of violence or anxiety about violence can expect their lives to be dominated by stress and its effects. Violence arises from either,

 a) the context of the work, for example:

transport workers being assaulted by drunks and muggers education workers being verbally and physically attacked care workers being assaulted and injured by those in their care people working with money being robbed travelling service workers being attacked on visits

Or,

b) the system of work, for example:

verbal abuse from line managers who lack supervisory skills "rat-packing" (the situation where, when one person begins to pick on another, others join in so that all are now picking on the victim) and other forms of scapegoating by peers sexual and racial harassment or abuse open and implied management threats, used as "stimulators" unnecessary application of workplace disciplinary codes

At Essex University, a joint staff union, management and student union group has set up a team of Harassment Advisers as part of their equal opportunities programme. As well as dealing with sexual and racial harassment, advisers have been asked to deal with incidents of bullying. Although no formal evaluation of the project has yet taken place, the initial stages have produced encouraging results.

Many employers are loath to tackle violence at work and will go to extreme lengths to avoid reducing it. A bus drivers' branch of the Transport and General Workers Union was de-recognised by their company because they put management under pressure to install safety screens to partially protect drivers from attack from behind. Yet, other bus companies have applied to Traffic Commissioners to withdraw services from routes dangerous to their drivers.

Employers often use forms of violence as a "management" control technique. Abusive line managers who threaten and frighten workers are not seen as "attackers" but can be rewarded by productivity payments for their bullying behaviour. They are not disciplined for their despicable actions.

The HSE defines violence as,

"any incident in which an employee is abused, threatened or assaulted by a member of the public in circumstances arising from her or his employment."

This is a restrictive definition that reflects the HSE's apparent concession to employer's lobbies. It is clear that there is a contradiction in the HSE's position on violence: violent behaviour towards an employee by a "member of the public" is violence but exactly the same behaviour by a working colleague or manager is not.

The important point in terms of tackling and eliminating violence at work is to ignore the artificial category being promoted by the HSE and to treat all violence as the hazard to health that it indisputably is. In Part 3 we set out some of the elements which should be incorporated in any policy on tackling violence at work.

Physical conditions

A working environment designed without consideration of individual worker's needs, which is uncomfortable, unsafe or unhealthy, can cause stress or add to stress caused by psychosocial factors. Equipment manufactured for use in work frequently takes no account of the physical characteristics of those who will operate it. It may be introduced into the workplace without considering its effect on temperature, noise, ventilation and overcrowding.

Noise

High levels of noise directly damage the middle and inner ears causing impairment of hearing. Lower levels can interfere with communication and, particularly if prolonged, cause anxiety, irritability and tension, increase fatigue and affect efficiency (Cox 1993). A 1992 study of more than 2,000 blue collar workers over a two year period found that exposure to noise, even below levels considered harmful to hearing, caused high levels of distress, anxiety, accidents and sick leave (Melamed et al 1992). As well as causing symptoms of mental ill health, workers exposed for long periods of time to high noise levels have a high incidence of allergies, respiratory and digestive disorders and musculo-skeletal and heart problems (Cox 1993).

Who suffers most?

In its 1992 publication on preventing stress at work, the International Labour Office (ILO) reported evidence that workers in a wide and growing range of occupations are at risk from stress. The following is a list of occupations with high stress levels which have been the subject of research studies. As conditions of work deteriorate throughout the cost-cutting 1990s, many other occupations may be added to this list.

Air traffic controllers Blue collar workers Bus and truck drivers Civil servants Construction workers Firefighters Healthcare professionals Journalists Miners Police Postal workers Social workers Teachers

More shop floor than top floor

Contrary to popular opinion, recent research shows that stress-related illness is lowest among professional and managerial groups and highest among blue-collar workers (Independent on Sunday 28 November 1993). Early results from a large-scale, community-wide survey being carried out by Professor Cooper showed high levels of stress amongst people with low levels of job satisfaction, often those employed on repetitive menial tasks.

Women

Recent studies have shown that women workers are at greater risk of stress-related illness than men doing the same job. This is not (as is sometimes claimed) because of some physiological weakness peculiar to women, but because they have, on average, significantly less control at work. Women are over-represented in areas of employment in which they have little control, such as the retail, office work, garment, catering, healthcare and outworking (homeworking) industries. Sexual harassment, reported by 70 per cent of women surveyed in London, adds significantly to stress at work.

Taking into account women's paid work in the workplace, and unpaid work at home, a woman with two or three children works 80-90 hours per week. Managing two jobs can make life difficult and stressful, for example trying to fit shopping into a lunch break or needing time off work when children are sick. Family responsibilities often dictate how far they can travel for work, and for some this means working in the home, where they remain isolated, and easily exploited. Women are more vulnerable in times of economic recession where their jobs (especially part-time jobs) are the first to go. There is little provision of services that might help to alleviate some of the stress, such as affordable childcare facilities and improved public transport.

In the previous sections we have looked at the symptoms, effects and causes of stress on workers' health and wellbeing. In Part 3 we look at strategies for the prevention of stress, employers' duties, the law and the trade union response.