Clean air in schools makes for better learning environment for students and teachers

The experts tell us that clean air is good for brains — particularly young brains — and good learning emerges with clean air.

But the practitioners too are aware of this: Dapto High School in Wollongong was “shrouded in smoke” during the Black Summer of 2019-20, Principal Andrew Fitzsimons recalls.

He’d already been talking to University of New South Wales researchers about monitoring air quality, following a UNSW workshop earlier that year, which he describes as “a revelation”.

“So when there was an opportunity to have our air monitored, I jumped at it,” he says.

Now with two years of data from the pilot project, he can confidently say that “the air at Dapto is remarkably good, bushfires aside,” although there’s always room for improvement.

He’s now a firm believer in the benefits of opening windows, provided the air is clear outside. And there are other benefits for students and staff. 

“In our maths and science faculties, we like to use real data (and) COVID has taught us just how important it is to have good ventilation,” Fitzsimons says. “So all of those things tie together.”

“Clean air is good for brains, particularly young brains. Good learning emerges with clean air.”

In Australia, we tend to think our children are breathing safe, clean, fresh air at school, especially indoors. But it’s hard to know for sure because no-one checks.

We tend to think our children are breathing safe, clean, air at school, but it’s hard to know for sure because no-one checks.

At least, that was the case until researchers at UNSW started asking questions.

Concern about the lack of data prompted a collaboration with a technology company producing low-cost air quality sensors; a pilot study; and now, a research project involving 100 schools.

UNSW Associate Professor Donna Green says the program could be easily extended – all it would take is funding and a willingness to participate.

Now that her team has “ironed out the kinks” and has scaled up from six to 100 schools, she can see the benefits of a national roll-out. She says the “plug and play, post-ready, monitors-in-a-box” design enables schools anywhere in Australia to get set up quickly and start checking air quality.

The idea’s genesis came in 2019, with the realisation that information about indoor air quality in schools was virtually non-existent. That thought was crystalised in the Black Summer of bushfires that followed.

“I remember asking why we didn’t measure indoor air pollution in Australia. All of our air quality readings are taken outside under what’s called ambient, or background, conditions,” Green says.

“They are not really representative of the air quality in urban areas where many schools are located, and they don’t really tell you much about what you’re exposed to inside those schools.

“I thought, well, we can fix that. Using low-cost sensors inside and outside school buildings, we can find out the actual levels of air pollution. This knowledge would be especially important to provide guidance during heatwaves and bushfires.

“We need to know what the indoor conditions are because that’s where people are up to 80 per cent of the time.”

Information about indoor air quality in schools was virtually non-existent. That thought was crystalised in the Black Summer of bushfires.

High-quality, calibrated sensors have recently become more affordable, allowing researchers to embark on the study comparing indoor and outdoor air quality. This is all being done to inform policies that will help keep the indoor school environment “good for children’s health and good for learning”.

“I had hoped this information was already out there so we could work on policies straight away,” Green says. “When I found it wasn’t, I realised someone had to design a program to collect the data. CleanAir Schools was the result.”

Each school participating in the program will have two air quality sensors (one indoors and one outdoors) managed by the CleanAir Schools team.

These automated sensors measure particulate matter 2.5 (PM_2.5) and nitrogen dioxide (NO₂). Paired indoor/outdoor weather stations measure carbon dioxide (CO₂), temperature, and relative humidity.

Readings are taken at 15-minute intervals, and the data is available in real-time and transmitted via mobile networks to avoid the difficulties of securing reliable Wi-Fi connections.

Teachers can access their school’s air quality readings online. The project team provides guidance on interpreting the information and developing STEM learning materials to go with it.

Green and her team are keen to study what she describes as “a very interesting data set that doesn’t exist anywhere else in the world”.

High-quality, calibrated sensors have recently become more affordable, allowing researchers to embark on the study comparing indoor and outdoor air quality.

“Alongside understanding how localised PM_2.5 readings vary between indoor and outdoors, we would also like to start looking at factors (such as) proximity to road or green space, because that will affect NO₂ levels from traffic pollution,” she says.

“We can also see what’s going on with carbon dioxide levels inside the school, and how closing windows might reduce outdoor PM_2.5 entering the building through open windows, but might increase CO₂ levels inside, and as a consequence, increase the risk of transmitting airborne viruses.”

Green says that CleanAir Schools plans to identify indoor air quality issues and work to improve them, providing “simple, straightforward guidance” to help reduce PM_2.5, NO₂ and CO₂ levels.

She’s thinking of the benefits, for the children and for society as a whole.

“If we can protect their health at school now, not only are there individual benefits to them, but Australian society as a whole will benefit,” she says.

Within the World Health Organisation and among air quality professionals, there’s a growing realisation that even low levels of air pollution can be harmful.

But it can be difficult to engage policymakers because fine particles and pollutants such as nitrogen dioxide are invisible and odourless.

“If you can’t see it or smell it, it’s not tangible or tactile, you tend to not think it’s a problem,” Green says.

“But what we’re realising, more and more, is that even at low levels, these pollutants do affect all the systems in the body, they can go through your lungs, into your blood, through the blood-brain barrier.

“That’s something that has only recently been recognised, and with more stressors, such as more heatwaves due to climate change, it adds more stress to the body.”

It can be difficult to engage policymakers because fine particles and pollutants such as nitrogen dioxide are invisible and odourless.

On top of that, most Australians, including children, have had COVID, which can have multiple, cumulative, lasting effects that can be exacerbated by poor quality air.

So while “generally we saw good air quality, inside and outside those schools (in the limited pilot study), it’s not quite as good as most people would like to believe. And there are ways we can suggest to improve indoor conditions,” Green says.

Updated WHO global air quality guidelines released in 2021 focus on six pollutants: ‎PM2.5, PM10‎, ozone, nitrogen dioxide, sulphur dioxide and carbon monoxide.

Following a comprehensive review of the evidence on the health impacts of these air pollutants, the WHO says: “The burden of disease attributable to air pollution is now estimated to be on a par with other major global health risks such as unhealthy diets and tobacco smoking.”

Air pollution is a “risk factor for diseases such as ischaemic heart disease, stroke, chronic obstructive pulmonary disease, asthma and cancer”.

It is hoped that policymakers will now “use these guidelines to inform evidence-based legislation and policies to improve air quality and reduce the unacceptable health burden that results from air pollution”.

But it won’t be easy, as Queensland University of Technology Professor Lidia Morawska and co-authors explain in their Medical Journal of Australia paper: “Healthy indoor air is our fundamental need: the time to act is now”.

That’s mainly because indoor air quality is a “regulatory no man’s land”.

“In Australia, as in most countries, there is no single national government authority with responsibility for indoor air quality, and any relevant legislation is at the discretion of individual states and territories, not the Commonwealth,” the authors wrote.