Shiftwork - Fundamentals and Assessment Tools for Occupational Ergonomics - page 646

Caffeine is widely used by shiftworkers in order to stay awake at work, and there is empirical evidence
from the laboratory that it is effective in improving alertness. However, it is important that shiftworkers
recognize that caffeine has a half-life of between 3 and 5 h. Because of the fragility of day sleeps discussed
earlier, it is important that night workers do not further worsen their day sleep by having caffeine still in
their bloodstream when attempting a day sleep. Thus, night workers should not consume any caffeine
after 4 am. 12
32.4 Domestic Factors
Human beings are essentially social creatures, and one could argue, as Walker 42 and others 43 have done,
that the social and domestic factors are at least as important in shiftwork as the biological ones. Certainly,
if a shiftworker's domestic and social life is unsatisfactory, then the individual will not be coping
satisfactorily, however well adjusted the sleep and circadian rhythm factors may be. In a Connecticut
shiftwork study conducted by the author, the intervention included elaborate specification of sleep
and wake times and education in circadian and sleep hygiene principles. The importance of social and
domestic factors was made clear when one participant pointed out that “Your advice is all well and
good, but right now things for me are so bad at home with my wife that I am sleeping out in
the car!” Thus, poor domestic adjustment can seriously affect the other two factors of the triad.
A common example concerns the childcare and household management tasks that can be expected of
a female shiftworker. Unlike her male colleagues, she is often expected by her spouse to continue to
run the household and can thus find herself completely unable to comply with the routine that good
sleep hygiene and circadian adjustment might require.
Another aspect of domestic disruption concerns the role of the male shiftworker as husband and
parent. With regard to the former, there are three major spouse roles that are affected: sexual partner,
social companion, and protector-caregiver. All three roles are compromised. Perhaps as a consequence,
shiftwork has been shown in a longitudinal follow-up study to increase the risk of divorce by 57%. 44 The
evening shift, which has minimal impact on the sleep and circadian factors, can have a crushing impact
on the role of the shiftworker as social companion. With regard to the family role of parent, the evening
shift is again the most disruptive. Often during the school week the shiftworker may only get to see his or
her children when they are asleep in bed. In addition, both spouse and parent roles are heavily disrupted
when the shiftworker is required to work on weekends.
In addition to disrupted family roles, the shiftworker often suffers from social isolation from day-
working friends and from religious, sporting, and community organizations that work under the expec-
tation that evenings or weekends will be free for meetings and activities. One might advance the view that
perhaps a shiftworker who is denied access to community meetings and sports, social, and political
associations is as much disadvantaged as a handicapped person who is denied wheelchair access to a
museum.
32.5 Solutions
The best approach to the challenge of shiftwork is one that involves both management and the work
force. 3 Corporate safety officers and medical officers can be extremely helpful in this regard because
they are skilled at bridging the gap between workers and managers, and at developing long-running
education and awareness programs. Management should realize that it has not only a moral but also a
financial obligation to be sensitive to issues of shiftwork tolerance in the training of its employees and
in the selection of shift schedules. Increasing medical, recruiting, and retraining costs dictate that
poor employee morale, higher job turnover, and increased accident, ill-health and absenteeism rates
resulting from shiftwork intolerance can become a financial burden to the company or organization.
Employee education programs should emphasize the way in which circadian, sleep, and domestic
factors can influence shiftwork coping ability. Workers should be taught good sleep hygiene practice