HEPA filters a breath of fresh air in bushfire season

by Sophie Berrill
0 comment

Portable air purifiers fitted with high-efficiency particulate air (HEPA) filters can substantially improve indoor air quality during bushfire events, according to new research from Australia’s national science agency, CSIRO.

Research published yesterday in Public Health Research and Practice found that HEPA filters have the potential, when used appropriately, to substantially improve indoor air quality by 30-74 percent during smoke episodes caused by planned burns.

The findings could help to protect 2.7 million Australians currently affected by asthma and around 7 million more at elevated risk of developing health problems during extreme smoke events.

New evidence supports old advice about HEPA filters

Previous research found a 44 percent increase of patients reporting asthma symptoms and presenting to emergency departments over one week during the Black Summer bushfires in January 2020.

While agencies often recommend vulnerable individuals use portable HEPA filters to reduce their exposure to smoke and stay inside, there has also been limited evidence so far that air purifiers fitted with HEPA filters reduce exposure or health risks to fine particulate matter, or PM2.5.

Lead author and CSIRO scientist Dr Amanda Wheeler says the results provide a strong point of evidence for agencies who are tasked with providing advice to the public during extreme smoke events.

“Staying inside and closing windows and doors during extreme smoke events is important, but ultimately what provides protection against smoke pollution indoors are air purifiers fitted with HEPA filters,” Dr Wheeler says.

“Using more than one, if possible, inside houses is likely to lead to improved health outcomes.”

While the research was focussed on prescribed burns, the findings are relevant for protection during bushfire events more generally.

“They demonstrate that any smoke emissions, including from neighbouring houses’ wood heaters can be managed better,” says Wheeler.

Tackling the greatest threat to Australian air quality

Dr Wheeler says that bushfires are the greatest threat to air quality in Australia, with climate change increasing the complexity of bushfire mitigation.

Increased temperatures are leading to increased fire events, which cause smoke pollution. Climate change is also extending the length of the summer bushfire season in southern parts of Australia, potentially prolonging smoke exposure and associated adverse health effects. Fire managers rely on prescribed burns to reduce fuel loads and mitigate the hazard of uncontrolled bushfires. 

“Prescribed burns are an important part of fire management, but outdoor smoke can easily infiltrate homes and buildings, so it’s critical that we find ways to protect populations from serious health impacts.” Dr Wheeler concludes.

Windows that generate electricity developed by CSIRO and Monash University were recently selected as finalists in Australia’s premier national science awards.

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept Read More