Published: 09 August 2022

Advice on heat stress, heat exhaustion and heatstroke

In heatwaves, significant increases in mortality can occur, especially in older people, young children and more vulnerable groups.

See tips and advice to help stay safe in the heat and to be mindful of heat stress, heat exhaustion and heatstroke.

Who is particularly vulnerable?

Heatwaves can affect anyone, but those most at risk are:

  • Babies and children.
  • People aged 65 and over.
  • People with underlying health conditions including problems with breathing, heart, kidneys and diabetes.
  • People with Alzheimer’s and dementia.
  • People who spend a lot of time outside or in hot places – those who work outdoors or the homeless.

How to keep cool

  • Minimise unnecessary heating. Turn off central heating, electrical equipment and lights that are not needed.
  • Keep out of the sun between 11 am and 3 pm when ultraviolet (UV) radiation is strongest. Stay in the shade or cover windows exposed to direct sunlight.
  • If you have to go outdoors, protect your skin by following the SunSmart 5 S’s – slip on clothing that covers skin, slop on sunscreen of SPF 30+ for adults and 50+ for children, slap on a wide-brimmed hat, seek shade and slide on sunglasses.
  • Use natural ventilation such as open windows when the air feels cooler outside than inside (for example at night) and where it is safe, secure and feasible to do so.
  • Increase air flow through buildings wherever possible.
  • Evaporative cooling – dampening your skin may help keep you cool.
  • If you are using air conditioning, make sure it is using a fresh air supply, which is important to prevent the spread of COVID-19.
  • Electric fans need to be used with caution, as they may not be safe for higher temperatures and should not be used where a person may be isolating for a case of COVID-19

Ways to stay hydrated

  • Make sure you have enough water to drink.
  • An adult needs approximately 2 litres of water over 24 hours. This may be less for smaller people or those with medical conditions.
  • Drink more fluids when you feel any dehydration symptoms. The best fluids to drink are water or oral rehydration sachets – chat to your pharmacist about how to use these safely.
  • Drink enough during the day so your urine is a pale clear colour


The person you are caring for may not have a sense of how much they're drinking.
To help them:

  • Make sure they drink during mealtimes.
  • Make drinking a social thing, like "having a cup of tea".
  • Offer them food with a high water content – for example, ice cream or jellies, or fruits like melon

Non-urgent advice: When to get medical help

Contact your GP or the Emergency Department if you are unwell and especially if you are experiencing any of the following:

  • feel confused and disorientated
  • feel very dizzy
  • have not urinated all-day
  • feel like your heart is beating fast
  • have fits (seizures)
  • are caring for someone who is drowsy or difficult to wake.

These can be signs of serious dehydration that need urgent treatment.