Work Health and Safety Heat Related Illness

Heat Related Illness

Sun close up.

Australia is well known for its temperature extremes, with scorching hot summers. Working in hot and/or humid environments can be uncomfortable, but more importantly lead to a heat-related illness, which can be fatal.

Heat is a hazard that can cause heat-related illness. Preventative strategies are needed for both indoor and outdoor work environments to address the risks working in heat poses for workers, as well as potential losses in productivity.

The Work Health and Safety Act 2011 (Qld) requires employers to provide and maintain, so far as reasonably practicable, a working environment in which workers are not exposed to hazards.  This applies to any risk to safety and health including illness from working in heat.

Fact Sheet 2022 - Heat Related Illness

Watch SafeWork South  Australia's Film on Heat Awareness

Heat stress tools can be useful. These tools can provide an indication of the level of risk, suggesting that further control is required. They are not an indication of whether work should proceed or not.

Sports Medicine Australia - Extreme Heat

A great resource developed by the leading Sports Medicine Organisation in the world. Discusses assessing heat related illness risk for various physical activities and cooling strategies amongst other topics.

Heat Stress Calculator - eTool from Work Health and Safety QLD

Online calculator to provide guidance on heat

Heat Stress factors combine to create a total heat load on the body. Heat sources can come from:

  • Humidity
  • Temperature
  • PPE/Clothing
  • Metabolic Heart
  • Radiant Heat
  • Air  Movement

Supervisors and workers should assess these factors and work to eliminate these risks or use other safety controls such as substitution, isolation, engineering or administrative actions to minimise the hazards. Refer to WHS-PRO-002 WHS Risk Management Procedure (Section 3) for more information and guidance on using these controls.

Key controls:

  • Schedule more physically demanding tasks for the cooler parts of the day during November to February
  • Use equipment or plant to reduce physical demands (e.g. ride on mower instead of push mower)
  • Install temporary shade
  • Increase air movement using fan
  • Modify reflective surfaces
  • Increase work break frequency, job rotation of tasks and slow down the pace of work if possible
  • Wear loose fitting, lightweight clothes or self-cooling garments
  • Keep an eye on new coworkers, who are not fully acclimatised to our extremes of temperatures
  • Take breaks during the day in cool, shaded areas or air-conditioned room to bring your core temperature down
  • Try drinking cold fluids or ice slushies before physical activity. Note that cold water and ice slushy ingestion during physical activity is actually less effective for cooling!
  • Water dousing – wetting your skin with cool water using a sponge or a spray bottle helps to increase evaporation
  • Placing an ice pack or damp towel filled with crushed ice around your neck
  • Wrapping in a tarp filled with ice slurry—ice water cooling (immersion and ice tarp ‘taco’) cools the core by 0.2°C per minute, which is twice as fast as enhancing evaporative cooling by covering the body in soaked towels. Great option for field work.
  • TACO method - Reference: Link

You - Self Monitor early warning signsCoworker - What to look for when monitoring others
  • Thirsty
  • Dry Lips and tongue
  • Slowed mental function / low performance
  • Reduced or dark urine
  • Inability to continue the activity
  • High body temperature
  • Dizziness and faintness
  • Nausea, vomiting or diarrhoea
  • Pale skin and other signs of shock
  • Dry skin
  • Poor muscle control or weakness
  • Decreasing levels of consciousness, confusion or seizures

Refer to First Aid for the type of action depending on the symptoms.

Suspected heat stroke requires immediate vigorous cooling to avoid neurological damage.

Ice-water immersion is the most effective means of cooling, working twice as fast as evaporative cooling using sprayed water and fans.


First Aid


Heat rash

  • Itchy rash with small raised red   spots on the face, neck, back, chest or thighs.
  • Move to a cooler, less humid environment.
  • Keep the affected area dry and remove unnecessary clothing, including PPE.

Apply a cold compress.

Seek medical advice if symptoms don’t improve


  • Mild to severe thirst (remember   that thirst is satisfied before fluid loss is fully replaced).
  • Dry lips and tongue.
  • Slowed mental function and   lowered performance.
  • Reduced or dark urine output.
  • Drink water. Avoid caffeinated, carbonated and alcoholic drinks, and salt tablets.
  • Loosen tight clothing and remove unnecessary clothing, including PPE.
  • In cases of extreme heat or dehydration, replace electrolytes.

Seek medical advice if symptoms don’t improve or are severe.

Heat Cramps

  • Painful and often incapacitating   cramps in muscles, particularly when undertaking demanding physical work.
  • Stop activity and rest quietly in a cool place until recovered.
  • Eat food or if unable to eat, drink an electrolyte solution.

Seek medical advice if symptoms don’t improve


  • Fainting (heat syncope) can   occur while standing or rising from a sitting position.
  • Lie the Worker flat   immediately with their legs slightly raised.
  • Do not raise the head.
  • Treat as for heat stroke and follow medical advice.

Seek medical advice

Heat Stroke

  • Dehydration, thirst, and   reduced or dark urine output.
  • Sweating.
  • The person stops sweating.
  • Skin can be pink, warm and   dry, or cool and blue.
  • High body temperature above   39 C.
  • Weakness or fatigue.
  • Pounding, rapid pulse.
  • Headache, dizziness and visual   disturbances.
  • Muscle cramps.
  • Nausea and/or vomiting.
  • Clumsiness or slower reaction times.
  • Disorientation or impaired judgement.
  • Tingling or numbness in fingers   or toes.
  • Rapid or short breathing.
  • Rapid weak pulse or heart   palpitations.
  • Vomiting or an unwillingness   to drink.
  • Irritability and mental   confusion.
  • Collapse, seizures and   unconsciousness.

While waiting for the ambulance:

  • Move the Worker to a cool place with circulating air.
  • Loosen and remove excessive clothing, including PPE
  • Immerse Worker in a bath of cold water (whole-body from the neck   down) in a bath of cold water (preferably 1–7˚) for 15 minutes. Continuously   observe the Worker to ensure breathing and conscious.
  • If immersion is not possible, use any combination of the options   below:
    • Cool the Worker by splashing   cool or cold water on their skin or sponging their skin with a damp cloth.
    • Make a wind tunnel by   suspending sheets around, not on, the Worker’s body.
    • Use a fan to direct gentle   airflow over the Worker’s body.  Fan   continuously.
    • Apply cold packs or wrapped   ice to the Worker’s neck, groin and armpits.
  • If the Worker is conscious sit them up to drink cool fluid and   electrolyte solution with sugar.
  • Shivering will make the body temperature rise even further. If   the Worker starts shivering, stop cooling immediately and cover them until   they stop. Once they have stopped recommence first aid treatment.

Call an ambulance immediately