Mould-related closures and new national evidence are driving urgency around indoor air quality, with filtration and ventilation emerging as key considerations for school leaders.
A significant mould outbreak that forced the closure of Willyama High School in Broken Hill in 2024 has sharpened focus on indoor air quality (IAQ) risks in Australian schools, with more than 600 students and staff displaced after buildings were deemed unsafe.
The disruption reflects a broader issue facing school systems: when indoor environments fail, learning stops. Other reported cases of mould exposure in schools have triggered health concerns, investigations and temporary closures, reinforcing the operational risks tied to poor air quality.
A 2024 national evidence review examines how indoor air quality influences airborne disease transmission in public buildings, including schools. The report identifies four key strategies to improve indoor air quality:
- Air cleaning (eg HEPA filtration)
- Air disinfection (eg UVC systems)
- Ventilation (introducing outdoor air)
- Airflow control within spaces
Indoor air quality concerns extend beyond airborne disease to include mould, volatile organic compounds and particulate matter, all of which can affect health, comfort and attendance.
Combining HEPA filtration with UVC sanitisation removes 99.97 per cent of indoor air contaminants or VOC’s, reducing the spread of COVID 19, Influenza, common colds and other airborne transmissible diseases.
Implications for school operations
For school leaders, IAQ is increasingly linked to operational continuity and risk management.
- Poor air quality has been associated with health impacts, absenteeism and reduced productivity
- Students and staff spend extended periods indoors, increasing exposure
- Building-related issues such as mould can lead to closures, relocations and costly remediation
- Ventilation and filtration performance can vary significantly depending on building design and usage
The report also highlights practical constraints. Larger spaces may require commercial-scale filtration units, which can introduce noise challenges in classrooms, while HVAC upgrades can be complex and costly.
Natural ventilation is not always reliable due to weather, building design or external pollution, and no single monitoring method can directly measure infection risk.
Policy settings add further complexity. Australia currently has no specific IAQ regulation outside workplace health and safety frameworks, leaving schools to navigate decisions across jurisdictions.
According to Mr Colin Bell, Proprietor of Purified Air Australia, the issue was escalated through federal channels following engagement with Independent MP Dr Sophie Scamps. Mr Bell said Dr Scamps raised indoor air quality in the House of Representatives, prompting a rapid parliamentary response and the commissioning of the national evidence review.
The report concludes that IAQ strategies are most effective when implemented as part of a broader, integrated approach tailored to each space. Mr Bell said recent changes to Work Health and Safety laws mean workplace exposure standards will transition to workplace exposure limits (WEL) from 1 December 2026, reinforcing that these values are limits not to be exceeded.
What schools should do next
- Review ventilation, airflow and known risk areas such as older buildings or moisture-prone spaces
- Consider where air cleaning or filtration may supplement existing systems
- Ensure any systems are appropriately sized and positioned for classrooms and shared areas
- Combine ventilation, filtration and maintenance strategies rather than relying on a single intervention.
Purified Air Australia is offering a 20 per cent promotional discount to all schools and aged care facilities. For more information, visit www.purifiedairaustralia.com.au or call 1300 571 671.
