During the twentieth century, extreme heat events were
responsible for more deaths in Australia than any other natural
hazard but few people are aware of the dangers of heat stress.
Extreme heat is a unique natural hazard because the effects are
primarily on human health rather than potential property damage as
in the case of other natural hazards. There is a spectrum of
potential impacts from extreme heat ranging from increased rates of
illness and minor disruption to society, to severely increased
rates of illness, death and major disruption to society with wide
ranging consequences (PricewaterhouseCoopers, 2011). Another
important factor is the confluence of hazards, as during an extreme
heat event the risk of bushfire is increased, further stretching
emergency response efforts.
Our changing climate is predicted to increase the frequency and
severity of extreme heat events. CSIRO and the Bureau of
Meteorology (BOM) report that the "Australian annual-average daily
maximum temperatures have increased by 0.75°C since 1910 and that
the Australian annual-average daily mean temperatures showed little
change from 1910 to 1950 but have progressively warmed since,
increasing by 0.9 °C from 1910 to 2011" (CSIRO, BOM, 2012). These
small changes in average temperature will have a significant impact
on the number of hot days and heatwaves that occur (OEH, 2011).
There are lots of simple steps you can take to prepare your
home, yourself and to help others before and during an extreme heat
event. Before an extreme heat event you can make changes to your
home that will help make your home a cooler space and make a plan
of action for during the extreme heat event. During an extreme heat
event you can activate your plan and carry out simple steps to help
you and others around you cope in the heat. Many of the home
preparation options will also provide other benefits such as
improvements in indoor air quality and reduced exposure to extreme
Extreme heat includes 'hot days' and 'heatwaves'. The working
definition for a hot day is a day with a maximum temperature, above
a set threshold (this threshold varies by location). A
heatwave occurs when there are a number of consecutive days with
above average temperature, often combined with high humidity
(Emergency Management QLD, QLD Government, 2012).
Who is most at risk in extreme heat events?
Extreme heat can affect everyone, but depending on a number of
factors it can impact some people more than others. The risk of
heat-related illnesses increases with natural ageing but people
with particular social and/or physical vulnerability are also more
at risk (Kovats & Hajat, 2008). Vulnerable population
groups include people with the following characteristics or
circumstances, although the links are not clear in all
- older people (65 years and older)
- children under five years old
- pregnant or nursing mothers
- people with a pre-existing medical condition, such as diabetes,
heart-disease, kidney disease or mental illness.
- people with a condition that impairs the body's abilities to
regulate its own temperature like Multiple Sclerosis
- those living alone with little social contact
- people taking certain medications, such as those for depression
or insomnia, people with a disability.
- people without air-conditioning or who decide not to use
- homeless people
- low income earners
- those with limited access to transport
- people who are outdoors for any reason, especially doing
strenuous activity like working or playing sports
- residents in the upper floors of multi-storey buildings
- some people from culturally and linguistically diverse
backgrounds who cannot access health services or information.
(Victorian Government, 2009).
Preliminary research suggests that extreme heat as a natural
hazard is most often dealt with through health and emergency
management messaging around the correct actions to take during an
extreme heat event. These active measures are likely to be most
effective during the extreme heat event but there is a number of
retrofitting and preparation measures that homeowners can take to
prepare and increase their resilience to extreme heat. These
particular measures focus on managing the thermal comfort inside
the home and should be used in conjunction with the active measures
PREPARE A PLAN
- Make a list of who you can call if you need help including
doctors or your nearest hospital.
- Make a list of cooler locations you could easily get to and how
to get to them such as your library, shopping centre or
- Prepare for likely health vulnerabilities: take advice from
your doctor if you have any medical conditions that might be
worsened in an extreme heat event.
- Regularly check your local forecast from the Bureau of
Meteorology on your radio, TV or on the internet.
- Extreme heat increases the risk of bushfire. Know what to do in
case of a bushfire. Information on bushfire preparedness is
available from the Queensland Rural Fire Service.
PREPARE YOUR HOUSE
- Put together a small emergency kit to plan for a possible power
failure - this may include a torch, batteries, candles, matches, a
battery operated radio and a first aid kit. For an example of what
to include in your emergency
kit. Keep your emergency kit in an easy to access area in case
of a power failure.
- If you will be out of the house during the day shade the
windows before you leave in the morning.
- Check that your home can be properly ventilated without
- Check your fridges, freezers, fans and air-conditioners to make
sure they work properly and make sure your air conditioning is set
PREPARE YOUR PANTRY
- Stock up on food (for your household and pets), water and
medicines to last up to a week so you don't have to go out in a
heatwave or if transport links are limited due to power supply
problems that can occur during extreme heat events. Consider buying
cool foods with high water content such as cucumbers and melons.
The colder these foods are when consumed the more they will help
you keep cool. Have food on hand that you can prepare without
cooking such as salads and sandwiches.
- Consider buying cool packs to have in the fridge or freezer to
help you cool down if needed.
PREPARE YOUR BODY
- Know the signs of heat stress so you can help
yourself and others should you need to. Types of work,
environment, air temperature, humidity and the physical condition
of an individual are all factors in the occurrence of heat
- Talk to your doctor about any issues you may have during an extreme heat
event such as side effects from particular medications.
- Get advice from your doctor about whether your medication
and/or your medical conditions may affect what you should do if it
gets extremely hot.
- If your doctor normally limits your fluids, check how much to
drink in hot weather.
- Check that you can store your medication at less than
25°C (some medications can become less effective or
occasionally toxic if stored at higher temperatures - check with
your pharmacist if unsure)
PREPARE YOUR GARDEN
- Add a thick layer of mulch around the base of the plant to
prevent excess moisture loss.
- Erect a shade structure out overheatsusceptible
- Wait until the heat has passed before cutting any affected
foliage as it helps protect the undergrowth.
- Water plants deeply before an expected extreme heat event.
- Move pots out of the direct sun and into a shaded
- Avoid fertilising stressed plants and instead use fortnightly
applications of liquid seaweed (Gardening Australia, ABC).