• What law applies
• Working in the sun and heat
  • The risks of working in the sun
  • Workers most at risk
• The sun and its health effects
• Sun safety measures
  • Sun exposure in Queensland
  • Controlling sun exposure
  • Personal protection
  • Sunscreen
  • Training
• Heat stress
  • Causes and sources of heat stress
  • Heat related illness
  • Hydration
• Artificial sources of ultra violet radiation

• Personal protective equipment
• Risk management

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Heat related illness

Heat stress can affect individuals in different ways, and some people are more susceptible to it than others either because of an illness or medication that may encourage the early onset of heat stress.

Heat related illness can occur when the body is unable to cool itself adequately and body temperature rises. This can be associated with different effects ranging from mild heat rash or cramps through to heat exhaustion or the more severe and potentially fatal heat stroke.

The warning signs to watch for include:

• painful muscles spasms or cramps
• heavy sweating
• difficulty in thinking clearly
• slurred speech
• blurred vision
• dizziness or fainting.

Types of heat related illnesses

Heat rash or prickly heat is an intense, itchy red skin rash. It is caused by a blockage of the sweat ducts from prolonged wetting of the skin. Treat by keeping the skin dry, wearing suitable clothing and moving to a cooler, less humid environment.

Heat cramps usually affect people who have sweated a lot during strenuous activity. These painful muscle cramps usually affect the abdomen, arms or legs. Cramps may be an early symptom of the more severe condition of heat exhaustion.

If medical attention is not necessary:

• stop all strenuous activity and rest quietly in a cool place
• increase fluid intake using cool water
• lay the person in the shade
• remove outer clothing (e.g. hard hat, boots, shirt)
• fan vigorously to increase evaporation.

Seek medical attention if the cramps continue for more than one hour.

Heat exhaustion is a serious condition that can develop into heat stroke. It is the body's response to depletion of fluid and salt due to sweating.

Warning signs include:

• heavy sweating
• paleness
• muscle cramps
• tiredness and weakness
• dizziness
• headache
• nausea
• vomiting
• fainting.

Lay the person in the shade, remove outer clothing, provide cool water and fan vigorously to increase evaporation. If symptoms are severe or don't improve seek medical attention immediately.

Heat stroke is a medical emergency, caused by a rise in core body temperature. A person suffering heat stroke becomes confused, and may stagger or collapse. The skin may be either dry or wet.

Call an ambulance and apply urgent first aid. Remove outer clothing, wet the skin and fan vigorously to increase evaporation.