7. WHY ARE SHIFT WORK AND
EXTENDED WORKING HOURS
HAZARDOUS?
Most people will be affected by working shift work and/or
extended hours. Irregular rosters, long hours and shift
work, particularly night shifts, create and/or worsen a
range of OHS hazards. While shift work and extended
working hours are not identical in the ways they affect the
health and safety of employees, their increasing
interrelationship in working arrangements requires that
they be considered together.
Shift work and extended hours can also affect the social
and domestic lives of employees and their families. Night
shifts, afternoon shifts and weekend work cause the main
problems, because they may be out of phase with the rest
of the community, particularly family and friends.
The interaction between health and safety effects and the
impacts on family and social life can have significant
outcomes for the general health of those working shift
work and extended hours.
Health and safety effects
• changes in natural body rhythms
• ongoing sleep problems
• increased physical and mental fatigue
• concentration difficulties
• increased risk of accidents
• increased exposure to hazardous substances,
noise and manual handling risks
• increased risk of heart disease
• menstrual problems and difficulties during
pregnancy
• disturbed eating patterns and poor diet
• gastrointestinal disorders and gastric and duodenal
ulcers
• more colds and other respiratory illnesses
• stress
• mood changes
• irritability and/or anger
• anxiety and depression
• use of alcohol and other drugs to overcome effects
of shift work