Thunderstorm asthma, raging bushfires, a worldwide pandemic—in the past few years, these events have brought the quality of the air we breathe, and the impacts on our health, into razor sharp focus.
Australia is home to some of the cleanest outdoor air in the world. But the quality of our health depends on wherever we are breathing air—whether that’s outdoors or indoors. And air quality changes the instant particulates and viruses enter our homes, schools, workplaces: our personal spaces.
These issues and more were explored in the recently released State of the Environment 2021 report.
CSIRO’s Dr Kathryn Emmerson co-led the air quality chapter. She also co-led the same chapter in 2016, and assessed Australia’s air quality then too.
“The air quality in Australia is generally still good,” Dr Emmerson said. “Which matches our findings from 2016. But since then, events such as the Black Summer bushfires show us the potential extremes of air quality. There is still a lot more we can do.”
Increasing access to real-time messaging
Singular events such as bushfires can cause air quality within cities and towns to drop from ‘very good’ to ‘very poor’ and ‘extremely poor’ within minutes. And unfortunately, with climate change, catastrophic events like these will only become more frequent.
The 2019/2020 bushfires blanketed Australia in dense smoke for weeks, which changed the way people accessed and used air quality data.
Having timely information on-hand means knowing in advance when there’s going to be a lot of smoke around, so you can get your house sealed beforehand.
“We want to move to a quicker method of getting real-time air quality information to the public,” Dr Emmerson said. “What we are trying to do is reduce the amount of smoke that might seep in and create a smokier situation inside the house than outside.”
The report includes a calendar of the 2019/2020 summer months in Canberra, where each day is coded according to its air quality. The boundary between ‘fair’ and ‘poor’ for fine particulate matter is 25 mg/m3—and the reading on 1 January 2020 was a whopping 962 mg/m3 (as a 24-hour average).
Tending to gaps under doors or around windows can make a world of difference to indoor air quality during a bushfire. The Canberra case study in the report found that sealing a house reduced five-minute readings from 1600 mg/m3 down to 300 mg/m3 inside.
Dr Emmerson says real-time air quality readings are also handy in letting the user know when it is safe to open up their house again, to flush clean air through.
The report reads, “the Bushfire Royal Commission recommended that air quality measurements are reported hourly, and that jurisdictions standardise how their air pollution health alert messaging is conveyed to the public.”
Dr Emmerson says the rise of personalised health technology, such as low-cost personal devices, apps and house-based gadgets has helped people access real-time data.
“These devices can help interpret whether there’s air pollution in our back yards, but the quality of these data varies greatly. The gold standard measurements are made by the network of air quality monitoring stations, and it’s hoped more stations can be commissioned.”
Good for you, good for your neighbours
The 2016 report also called for tighter controls around wood heater emissions. Most people complain about poor air quality when their neighbours are using domestic wood heaters.
A case study within the 2021 report highlights the localised effects of wood-heater smoke on air quality via a smoke-mapping survey in Tasmania.
“The air quality data was collected on a house-to-house level,” Dr Emmerson said. “And we found the effects of wood smoke varied not only from house-to-house but street-to-street.”
“With poorly operated wood heaters, you pollute your neighbours—chimney smoke drifts next door and gets trapped inside through leaky windows. So, the way you heat your house can really impact your own, and your neighbours’, quality of life.”
She says wood heaters in cities—where air conditions can stagnate at night and people are living in close proximity to each other—aren’t necessary. There are other forms of heating that aren’t as damaging.
The report says addressing behavioural change seems to be the best way to reduce the use of wood heaters. A buy-back scheme in Tasmania was successful but similar schemes are yet to be considered and implemented in other states and territories.
Overall findings
Dr Emmerson says periods of reduced air quality can exacerbate other health issues: asthma, heat stress, heart problems, reduced lung function—and, stress.
“Australia has very good air quality most of the time,” she said. “But the infrequent and extreme events we get can make it really bad.”
“There are things that improve local environments during extreme times,” Dr Emmerson said. “But you can’t escape poor air quality completely unless you have access to a clean room with HEPA filters that take out particles such as dust and viruses.”
The report outlines achieving a more effective management of air pollution through “better public transport, a move to cleaner energy systems, banning wood heaters in cities, introduction of stricter fuel standards for vehicles, implementing cleaner European vehicle technology standards, and holding industry to strict licence-to-operate standards.”
“We’ve certainly seen some improvements since the last report. Disastrous events have challenged Australians and humanity in a huge way since then, but now we’re learning from those too.”