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Beat the Heat

Ways to minimise the risk of dehydration while wildland firefighting

Firefighting in the bush is a physically demanding occupation. Strenuous work, hot weather and radiant heat places considerable stress on firefighters, requiring special precautions to be taken to avoid the risk of overheating the body.

How do you minimise the risk

Overexposure to heat can be minimised by:

  • wearing the correct clothing
  • adequate fluid intake
  • sensible work practices
  • appropriate rest periods.

    Correct Clothing

    Overalls, hardhat, leather boots are vital to your safety when working in wildfire environments. Protective clothing blocks radiant heat and protects you from environmental dangers, but they reduce the evaporation of sweat.

    To minimise overexposure to heat:

  • underneath overalls wear minimal clothing (shorts and t-shirt) made of cotton
  • make sure all clothes are loose fitting
  • when not working close to the fire, open the front of overalls and roll up sleeves.

    Never compromise your safety.

    Protection from radiant heat is vital to your survival, so always wear protective clothing; overalls, lace up, heat resistant boots, and your sleeves rolled down, collars up, if required.
        Adequate Fluid Intake

        Recent research has documented that sweat loss while working hard in hot environments can be up to 1.5 litres per hour. Firefighters will usually need to drink at least one litre per hour to remain hydrated. Fitter people sweat more and lose more water. Any weight loss identified immediately after work is mainly fluid. Before your next shift try and make up the difference, by drinking water.

        Photo: fluid intake
    To replace water lost during work
    .
            Drink water (about half a litre) before starting any physical work,

            Try to drink regularly while working. 150 - 200 ml (one large glass) of cool water every 10 - 15 minutes,

            Always drink water before you are thirsty,

            Continue to drink water after work has finished,

            Always carry drinking water with you.

    What to drink?

    Water is the best fluid to drink. If you must have a stronger taste, try weak cordial.

    Did you know?

    Stomach cramps are not caused by either drinking while working or drinking cold water.

    What not to drink.

            Don't drink soft drinks or fruit juices, (the sugar concentration is too high - they actually dehydrate you)

            Don't drink alcohol or excessive amounts of tea or coffee. All of these increase fluid loss from the body.

            Don't wait until you are thirsty. Thirst is a sign that your body is already dehydrated.

            Don't take salt tablets (loss of salt is not the major cause of body cramps). Cramps are usually caused by dehydration.

        Sensible work practices
      • Be physically fit and maintain a healthy body weight.
      • Be aware of any medications you are taking, and whether they dehydrate you or make you sleepy.
      • Be used to working outdoors and in the sun.
      • Rest in a shady place, when possible.
      • Watch your work mates for signs of fatigue and heat stress.
      • Rest in a shady place when possible.
        Photo: always rest
    Managing the Heat.

    Heat illness can occur whenever and wherever there are any of the following;

  • high temperatures, or
  • a requirement for the body to work strenuously, or
  • exposure to radiant heat.

    Overexposure to heat can lead to a decrease in physical and mental performance, resulting in an increased potential for errors and accidents.

    Three conditions are caused by overexposure to heat.

  • Sunburn
  • Heat Exhaustion
  • Heat Stroke

    These conditions may occur separately or in combination.

    Sunburn

    Sunburn is totally preventable. To prevent sunburn:

  • wear overalls,
  • wear sunglasses,
  • wear a sunblock, and reapply often,
  • wear hard hat neck flap or sun shade,
  • pull collar of overalls up.

    Heat Exhaustion

    Symptoms

    Initial symptoms of heat exhaustion are: faintness, muscle cramps, light headedness, dizziness, headache, nausea.

    The heat exhausted person usually has a rapid pulse, fast, shallow breathing, cold clammy skin and a pale face.

    Treatment

  • remove person to cool environment
  • sit or lie person down, elevate legs if feeling faint
  • give plenty of water
  • sponge skin with water
  • fan person to increase cooling.

    Heatstroke

    Heatstroke results when the body can no longer control its temperature.

    Symptoms

    Heatstroke symptoms are usually: dry skin, red face, full and bounding pulse and, noisy breathing.

    Treatment

    Treat as for heat exhaustion if person is conscious. If unconscious place in lateral position and monitor vital signs.

    Heatstroke is a medical emergency. Seek Medical Assistance immediately.