Snug but unsafe: your heater may be harming your health. What are your safest choices?
<p><em><a href="https://theconversation.com/profiles/christine-cowie-191638">Christine Cowie</a>, <a href="https://theconversation.com/institutions/unsw-sydney-1414">UNSW Sydney</a> and <a href="https://theconversation.com/profiles/bill-dodd-1280161">Bill Dodd</a>, <a href="https://theconversation.com/institutions/university-of-tasmania-888"><em>University of Tasmania</em></a></em></p>
<p>We now have a dizzying array of heating technologies to consider, besides the fire that warmed our ancestors.</p>
<p>Salespeople will highlight any number of features and minor conveniences. You will be made aware of limited-offer discounts, product warranties, trends in certain Nordic countries, or their low cost (at least in the short-term). What you are less likely to read on the box is, well, the stuff that really matters: the long-term effects on your health and the health of your family, your neighbours and the environment.</p>
<p>Yes, a heater should keep you warm affordably. After all, a warm home is vital for your health. But would you run a heater that you knew was increasing the likelihood of your child developing asthma, your partner developing lung cancer, and your neighbour or your grandparent suffering a stroke or heart attack?</p>
<p>Many <a href="https://doi.org/10.1016/j.envint.2019.105429">peer-reviewed studies</a> have found domestic heating to be a major source of air pollution and of ill health in Australia. So which heaters are high-risk and which are low-risk? Let’s consider, firstly, the most dangerous heaters.</p>
<h2>Extreme-risk heaters</h2>
<p>Two rules reduce the risks:</p>
<ol>
<li>
<p>never burn anything (wood, gas or other fuel) in your home without adequate ventilation such as a chimney, exhaust or flue</p>
</li>
<li>
<p>never use an outdoor appliance (heater, cooker, barbecue) inside.</p>
</li>
</ol>
<p>Concerningly, a 2022 <a href="https://asthma.org.au/wp-content/uploads/2022/11/AA2022_Housing-Survey-Report_full_v4.pdf">Asthma Australia survey</a> found 7% of Australians used an unflued gas heater.</p>
<p>When gas or other fuel is burnt indoors it releases a range of <a href="https://search.informit.org/doi/abs/10.3316/informit.786585213635569">particles and toxic gases</a>. Most dangerous of all is <a href="https://www.dcceew.gov.au/environment/protection/npi/substances/fact-sheets/carbon-monoxide-0">carbon monoxide</a> (CO). This colourless, odourless gas can build up in unventilated homes, resulting in serious poisoning and death.</p>
<p>A recent <a href="https://www.abc.net.au/news/2024-06-29/sydney-family-use-bbq-as-indoor-heater-inhale-carbon-monoxide/104039702">case of carbon monoxide intoxication</a> left three people unconscious in a Sydney home after an outdoor barbecue was used inside as a heater. Outdoor heaters, cookers and barbecues are especially potent sources of carbon monoxide and should never be brought inside.</p>
<p>If you have a gas appliance in your home, even if it is ventilated, install a <a href="https://www.energysafe.vic.gov.au/industry-guidance/gas/gas-information-sheets/gis-36-carbon-monoxide-alarms-domestic-use">carbon monoxide alarm</a> for as little as $30.</p>
<h2>High-risk heaters</h2>
<p><a href="https://www.sciencedirect.com/science/article/pii/S0048969724012087">The evidence</a> is now very clear: wood heater smoke is a potent source of air pollution and significant cause of ill-health in Australia.</p>
<p>The more often you burn, the greater the risk. One <a href="https://doi.org/10.1016/j.envint.2023.108128">large population study</a> found even infrequent wood heater use (30 days or more each year) increases the risk of lung cancer by 68%.</p>
<p>Wood heaters spill smoke into the home when refuelling. They also suck smoke from outside back into the home as air is drawn up the chimney.</p>
<p>If you can smell your wood heater, it is harming your health and exposing you to a toxic mix of particles and gases.</p>
<p>For the wider community, the cumulative health impacts of wood heaters are significant.</p>
<p>Less than <a href="https://www.abs.gov.au/ausstats/abs@.nsf/Previousproducts/4602.0.55.001Main%20Features5Mar%202011?opendocument&tabname=Summary&prodno=4602.0.55.001&issue=Mar%202011&num=&view=">10% of Australian households</a> use a wood heater. Yet they are the largest source of particulate air pollution in most Australian cities and towns, including <a href="https://www.environment.nsw.gov.au/-/media/OEH/Corporate-Site/Documents/Air/sydney-air-quality-study-stage-2-program-report-220644.pdf">Sydney</a>, <a href="http://www.doi.org/10.1016/j.scitotenv.2024.171069">Melbourne</a>, <a href="https://onlinelibrary.wiley.com/doi/full/10.5694/mja2.52176">Canberra</a>, <a href="http://www.doi.org/10.1016/j.scitotenv.2024.171069">Adelaide</a> and <a href="http://www.doi.org/10.3390/ijerph17093264">Hobart</a>. Even in temperate Sydney, wood heaters emit <a href="https://www.environment.nsw.gov.au/-/media/OEH/Corporate-Site/Documents/Air/sydney-air-quality-study-stage-2-program-report-220644.pdf">more of this pollution</a> than all the cars, trucks, boats and buses combined, and more than coal-fired power stations and industry.</p>
<p><a href="https://safeair.org.au/">Centre for Safe Air</a> researchers <a href="https://doi.org/10.1016/j.scitotenv.2024.171069">estimate</a> wood heaters cause between 558 and 1,555 excess deaths a year in Australia. That’s roughly equivalent to the <a href="https://www.bitre.gov.au/publications/ongoing/road_deaths_australia_monthly_bulletins">annual road toll</a>.</p>
<p>Fine particles (2.5 microns or less in diameter – also known as PM2.5) are a major component of wood smoke. PM2.5 increases <a href="https://www.epa.gov/air-research/air-pollution-and-cardiovascular-disease-basics">rates of heart disease and stroke</a>, <a href="https://doi.org/10.3978%2Fj.issn.2072-1439.2016.01.19">lung disease</a>, <a href="https://doi.org/10.1016/j.scitotenv.2018.11.218">dementia and other neurological conditions</a> and <a href="https://asthma.org.au/about-us/advocacy/air-quality">asthma attacks</a>. Risks of <a href="https://doi.org/10.1371/journal.pmed.1003718">adverse pregnancy outcomes</a> and <a href="https://www.eea.europa.eu/publications/air-pollution-and-childrens-health">poorer learning outcomes in children</a> are also increased.</p>
<h2>Low-risk heaters</h2>
<p>Evidence suggests there is no “safe” level of air pollution, with health effects <a href="https://doi.org/10.1016/j.envint.2019.02.044">seen at very low levels</a>.</p>
<p>Even ducted gas heating, where most of the toxins are ventilated, <a href="https://search.informit.org/doi/abs/10.3316/informit.786585213635569">can expose residents to low levels</a> of PM2.5, nitrogen dioxide (NO2), carbon monoxide and formaldehyde. Over time, this can have a range of <a href="https://safeair.org.au/the-health-impacts-of-gas-use-extraction/#gf_1">health impacts</a>, including worsening asthma and respiratory symptoms.</p>
<p>Burning gas for heating also adds to greenhouse gas emissions.</p>
<p>As Australia transitions to a zero-carbon society, some states and territories are phasing out installation of new wood heaters, such as <a href="https://www.abc.net.au/news/2023-08-24/canberra-to-phase-out-wood-heaters-by-2045/102769162">in the ACT</a>, and gas connections, such as <a href="https://www.planning.vic.gov.au/guides-and-resources/strategies-and-initiatives/victorias-gas-substitution-roadmap">in Victoria</a>. Subsidies to help people replace unhealthy heaters are excellent investments in the environment, public health and health equity.</p>
<h2>Healthy heaters</h2>
<p>Ultimately, heaters that do not rely on burning fuel inside the home are the safest, and often more affordable, heating option.</p>
<p>A <a href="https://www.abc.net.au/news/2023-07-17/cleaning-filters-in-reverse-cycle-air-conditioner-to-save/102594652">well-maintained</a> reverse-cycle air conditioner, sometimes called a heat pump, actually cleans the air inside your home.</p>
<p>These air conditioners have the additional benefit of cooling your home in summer. As heatwaves become more severe and frequent, efficient cooling is <a href="https://www.sciencedirect.com/science/article/pii/S0378778823004152">increasingly important for health</a>.</p>
<p>As for affordability, an efficient reverse-cycle air conditioner can be up to <a href="https://www.climatechoices.act.gov.au/__data/assets/pdf_file/0005/1862663/Sustainable-Household-Scheme-A-guide-to-reverse-cycle-systems.pdf">seven times as efficient</a> as a gas wall heater in the energy it uses for a given amount of heat.</p>
<p>There are many other <a href="https://www.choice.com.au/home-and-living/heating/electric-heaters/articles/which-electric-heater-type-is-best">electric heating technologies</a> – such as fan heaters, oil column heaters, panel heaters, or infrared heaters – that do not release toxins into the home.</p>
<p>Heater manufacturers are often reluctant to talk about the health impacts of their products, and regulators are slow to catch up with the science.</p>
<p>By thinking about heating in terms of health, you can make your home safer for yourself and the people around you.</p>
<p>After all, there’s nothing cosier than a healthy home.<img style="border: none !important; box-shadow: none !important; margin: 0 !important; max-height: 1px !important; max-width: 1px !important; min-height: 1px !important; min-width: 1px !important; opacity: 0 !important; outline: none !important; padding: 0 !important;" src="https://counter.theconversation.com/content/235102/count.gif?distributor=republish-lightbox-basic" alt="The Conversation" width="1" height="1" /></p>
<p><a href="https://theconversation.com/profiles/christine-cowie-191638"><em>Christine Cowie</em></a><em>, Senior Research Fellow, Centre for Air Quality and Health Research and Evaluation, Woolcock Institute of Medical Research, University of Sydney; Senior Research Fellow, South West Sydney Clinical School, <a href="https://theconversation.com/institutions/unsw-sydney-1414">UNSW Sydney</a> and <a href="https://theconversation.com/profiles/bill-dodd-1280161">Bill Dodd</a>, Knowledge Broker, Centre for Safe Air (NHMRC CRE), and Adjunct Researcher, Media School, <a href="https://theconversation.com/institutions/university-of-tasmania-888">University of Tasmania</a></em></p>
<p><em>Image </em><em>credits: Shutterstock </em></p>
<p><em>This article is republished from <a href="https://theconversation.com">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/snug-but-unsafe-your-heater-may-be-harming-your-health-what-are-your-safest-choices-235102">original article</a>.</em></p>
