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Extremes of temperature or humidity

Hazard Knowledge

The legislation refers to the specified risk of 'loss of consciousness arising from increased body temperature'. This could be the result of high atmospheric temperatures, humidity or a range of other factors.

Working in hot conditions can lead to a dangerous rise in core body temperature. This can be made worse by:

  • Wearing personal protective equipment (PPE)
  • Highly physical or strenuous work
  • Working at a high work rate

In extreme cases, heatstroke and unconsciousness can result.

Excessive heat can occur where:

  • Work is being carried out in hot conditions
  • The confined space is exposed to a significant heat source
  • Processes are being undertaken that generate significant amounts of residual heat

A slower heat build-up in the body can also cause heat stress. If action is not taken to cool the body, there is a risk of heatstroke and unconsciousness.