Heat Stress

You may experience heat stress on the fire ground depending on the duration of the incident, environmental conditions, workload and hydration status. It is important to recognise the signs and symptoms of heat related illness when involved in an incident.

What is heat stress?

Heat related illnesses such as heat cramps, heat stress, heat exhaustion and heat stroke are all forms of heat stress. Heat stress occurs when the body fails to maintain a normal and healthy core temperature (normothermia).

The onset of heat stress can be triggered by extreme temperatures or high workload.
The risk of heat stress for fire fighters is increased due to the nature of  their work, and work conditions i.e. hot, humid and dusty conditions, often within range of radiant heat whilst wearing personal protective clothing and equipment.

Types of heat illness 

  • Heat cramps
  • Heat exhaustion
  • Heat stroke
  • Hyponatremia
Signs and Symptoms
  • Headaches
  • Fatigue
  • Thirst
  • Dry skin
  • Light-headedness
  • Nausea
  • Dizziness
  • Changes in mood
  • Loss of coordination
  • Confusion
  • Loss of consciousness
What can you do?

Heat stress active cooling techniques should be followed to prevent and reduce the effects of heat stress.

Minimise heat stress on the fire ground by:

  • Adopt a comfortable, conservative pace on the fire ground
  • Share heavy workloads, and rotate crews
  • Work at a comfortable distance from the fire
  • Take regular breaks
  • Wear appropriate clothing (PPC) for the task being undertaken
  • Do not run on the fire ground

During rest periods active rehabilitation should include: 

  • Hydration – Up to 600mL of electrolyte drink to 1200mL of water every hour, pending workload.
  • Cool shaded area – where possible a grassed, shaded area should be used for rehabilitation
  • Lower arm cooling – using cooling chairs, cooling towels fans and/or water
  • Remove/loosen excess clothing – this promotes airflow and allows sweat to be evaporated from the skin