Lack of sleep and fatigue has the same effect on the body as alcohol, a conference on safety in a changing era for the workplace has been told.
Long working hours, long commutes, as well as increasing night shift work as Ireland moved more towards a round-the-clock society should mean a greater awareness of the risks of fatigue and shift-working, 400 delegates at the National Irish Safety Organisation conference in Killarney heard at the weekend.
The body had an internal clock which was more alert at certain times of the day and which controlled temperature as well as alertness, according to Mr Jeremy Williams, head of Human Factors Profession at the British Health and Safety Laboratory.
Alertness levels slipped at night and decreased further as the night proceeded. Shift workers were more susceptible to circulatory disease, digestive problems and fatigue.
Ultimately, the problems associated with disruption of sleep and fatigue could lead to premature death. "You can kill people by keeping them awake," he said.
Research in Britain had shown that bad shift patterns and lack of rest led to workplace accidents and health problems, Mr Williams continued. For every successive hour awake, performance worsened and error rates of as much as 200 per cent had been recorded.
Fatigue associated with lack of sleep had the same effect as alcohol consumption. "When you have been awake for 22 to 23 hours, you are in effect drunk. It has the equivalent effect on the body."
A minimum of 12 hours between shifts, an avoidance of "the quick return" of eight hours and a restriction on the number of night shifts to a maximum of four in a row were among guidelines drawn up in Britain.
The Minister for Labour Affairs, Mr Tony Killeen, said fatigue led to decreased vigilance, impaired problem-solving ability, decreased mood and motivation and increased error. Where shift work was concerned, "night shifts have inherent drawbacks", he said.