By nature, we all live to the tune of our internal clock or ‘circadian rhythm’. This pattern of living is imprinted in the brain and governs our waking and sleeping biological activities. Our heart rate, body temperature and blood rate is increased during the day, whereas at night these biological activities slow down. Shift work schedules require abrupt changes to this pattern. Our internal clock can change gradually but does take some time. Some individuals adapt easier than others. Where one doesn’t get enough sleep at the proper times (i.e. during the night) ,performance and errors are more likely. Although, it’s rarely possible to fully adjust to working at night or outside normal working hours, shift work can be managed to lessen to risk to the body and the work environment.
Short term effects of shift work include gastrointestinal problems, insomnia, a general feeling of unwell and increased risks of injuries. Long term effects can include cardiovascular disease, diabetes, obesity, depression, cancer and problems with fertility and pregnancy. Some of the serious risks can develop over decades and some over a shorter period of time. However, if you work in nursing, are a doctor, firefighter, or work in the police force or emergency services, or basically have to work at night, what can you do?
All employers, under the Health and Safety Act have a duty to ensure that they have minimised the risks to a level that is reasonably practical. Risk assessments should be carried out to ascertain the risks that workers may be exposed to. The risk assessment should take full account of the hazards associated with fatigue. It should also be established who might be harmed by shift work. Even though all workers are at risk from shift work, some might be more vulnerable than others. More vulnerable persons may include older workers, younger workers, expectant mothers, workers with pre-existing health conditions, temporary workers and sub-contractors who may find it difficult to adhere to current shift work patterns. Members of the public may also be at risk if they are in the environment where shift work takes place. Data should be collected about the shift work arrangements and used to identify areas where improvements can be made, if necessary. Past accident record books should be consulted. Shift workers should have safety representatives to speak on their behalf.
If practical, demanding work periods should be scheduled when workers are more alert, for example, at the beginning of a shift. Those who work on a more permanent night shift basis should have information regarding the risks. At shift handover, there should be brief communication liaison meeting so that the next set of shift workers are aware of the current situation. There should be adequate rest time between shifts. If practical, shifts should be rotated every 2 to 3 days as the internal body clock doesn’t adapt this quickly and sleep loss can be recovered. Permanent night time work and shifts of more than 8 hours should be avoided. Rest facilities and breaks should be part of the shift pattern. The work place temperature should be adjustable as the body cools down at night. Healthy living strategies should be promoted at work such as eating well, exercising and regular check-ups with the doctor.