8. Heat and cold
8.1.1. This chapter gives additional and specific information to help employers,
workers and competent authorities apply the general principles in Chapters 2 and 3. It
applies to conditions in which:
(a) temperatures and/or humidity are unusually high;
(b) workers are exposed to high radiant heat;
(c) high temperature and/or humidity occur in combination with protective clothing or
high work rate;
(d) temperatures are unusually low (e.g. in outdoor work during winter season, in cold
(e) high wind speeds (>5 m/s) prevail with unusually low temperatures;
(f) work with bare hands is carried out for extended periods of time at temperatures
below 15 °C.
8.1.2. Workers should be allowed sufficient time to acclimatize to an extremely
hot or cold environment, including major changes in climatic conditions.
8.1.3. This chapter does not deal with:
(a) risk of injury from contact with very hot or cold surfaces, but where these exist the
employer should take this risk into account in assessing control measures that are
(b) special measures required to protect against the effect of immersion in cold water,
by diving or by accident.
8.2.1. If workers are exposed for all or part of their tasks to any conditions listed
in paragraph 8.1.1 above and the hazards and risks cannot be eliminated, employers
should assess the hazard or risk to safety and health from the thermal conditions, and
determine the controls necessary to remove such hazards or risks or to reduce them to
the lowest practicable level.
8.2.2. The assessment for the thermal environment should take into account risks
arising from working with hazardous substances in work situations such as:
(a) the use of protective clothing against hazardous substances that may increase the
risk from heat stress; and