|The Occupational Safety and Health Act (OSH Act) requires employers to comply with hazard-specific safety and
health standards. In addition, pursuant to Section 5(a)(1) of the OSH Act, employers must provide their employees with a workplace
free from recognized hazards likely to cause death or serious physical harm. Emergency Preparedness Guides do not and cannot enlarge or
diminish an employer's obligations under the OSH Act.
Emergency Preparedness Guides are based on presently available information, as well as current occupational safety and health provisions
and standards. The procedures and practices discussed in Emergency Preparedness Guides may need to be modified when additional, relevant
information becomes available or when OSH Act standards are promulgated or modified.
What is an Extended/Unusual
Shift and when are they used?
A normal work shift is generally considered to be
a work period of no more than eight consecutive hours during the
day, five days a week with at least an eight-hour rest. Any shift
that incorporates more continuous hours, requires more consecutive
days of work, or requires work during the evening should be
considered extended or unusual. Extended shifts may be used to maximize
scarce resources. Long or unusual shifts are often required during response
and recovery phases of emergency situations such as terrorist threats,
which generally come without warning, require continuous monitoring,
and may overwhelm local responders both technically and tactically.
These schedules ensure that the appropriate scarce resources are
in place and accessible while full mobilization is being developed.
Is there an OSHA standard covering this?
Currently, there is not a specific OSHA Standard for extended
or unusual work shifts. This document is intended solely as a guide
to provide information to employers and workers.
What should workers know?
Extended or unusual work shifts may be more
stressful physically, mentally, and emotionally. Non-traditional shifts
and extended work hours may disrupt the body's regular schedule,
leading to increased fatigue, stress, and lack of concentration. These
effects lead to an increased risk of operator error, injuries and/or
Society is oriented toward traditional daytime
work hours and work at night will often intensify
fatigue and reduce alertness. Workers generally will not acclimate
to night work, and sleep patterns will generally be disrupted so the non-work
periods do not provide full recovery, resulting in sleep deprivation.
Studies suggest that it can take up to 10 days to adapt to a night time
Fatigue is a message to the body to rest. It is not a problem if the
person can and does rest. However, if rest is not possible, fatigue can
increase until it becomes distressing and eventually debilitating.
The symptoms of fatigue, both mental and physical, vary and depend on
the person and his or her degree of overexertion. Some examples include:
- reduced alertness, lack of concentration and memory
- lack of motivation
- increased susceptibility to illness
- loss of appetite and digestive problems
Emergency responders, particularly those who
are assigned to work for extended hours, must be aware of the
limitations of the protective equipment they use and the allowable
or safe duration of exposure to hazardous environments. It is not
practical or safe to wear some forms of protective equipment for
extended periods. Fatigue and heat-related illness are common
How can I address these hazards?
When there is a choice, managers should limit the use of extended shifts
and increase the number of days employees work. Working shifts longer
than 8 hours will generally result in reduced productivity and alertness.
Additional break periods and meals should be provided when shifts are
extended past normal work periods. Tasks that require heavy physical
labor or intense concentration should be performed at the beginning of
the shift if possible. This is an important consideration for
Managers and supervisors should learn to recognize signs and symptoms of the
potential health effects associated with extended and unusual work shifts.
Workers who are being asked to work extended or irregular shifts should be
diligently monitored for the signs and symptoms of fatigue. Any employee showing
such signs should be evaluated and possibly directed to leave the active area and seek rest.
Make efforts, whenever feasible, to ensure that unavoidable extended
work shifts and shift changes allow affected employees time for adequate
rest and recovery. Extended shifts should not be maintained for more
than a few days, especially if they require heavy physical or
Plan to have an adequate number of personnel available in order to
enable workers to take breaks, eat meals, relax, and sleep. If at
remote sites, ensure, as far as possible, that there is a quiet, secluded
area designated for rest and recuperation.
Plan for regular and frequent breaks throughout the work shift. In addition
to formal breaks such as lunch or dinner, encourage the use of micro breaks
to change positions, move about, and shift concentration.
In addition to fatigue, employers must ensure that employees are not
exposed to hazardous chemicals or other agents in excess of health
standards. Working extended shifts may involve prolonged exposures
to hazards which exceed established standards. Therefore, employers
should implement measures to monitor and limit exposures. Those may
include administrative controls such as limiting the time employees
may remain at the response site; engineering controls such as clean
locations for employee rest areas; or rest areas located
sufficiently up wind of contaminated sites.