It has been recognised that ventilation, along with other controls, is one of the most effective controls to help reduce the risk of infection of COVID-19.¹

The Department of Education (DoE) has a ventilation strategy for WA schools. An audit has been conducted of all schools, with a dot system developed for classrooms and other work areas.² You can see a guide to this system here. (Please note windows with a black dot require repair – this is not in the guidance material.)

The most effective ventilation method is cross ventilation in which new air flows into a space and disperses old air. The various natural ventilation of rooms is outlined in diagram one.

Diagram one:³

In classrooms or work areas where natural or mechanical ventilation cannot occur, DoE has provided schools with air purifiers to clean the existing air within the indoor space.

Schools have also been provided with CO2 monitors to monitor air quality.

Member concerns

If you have members who are concerned about their workspace/classroom, air monitoring should be conducted in the area.

Advice

As the health and safety rep (HSR), we advise you to:

1. Request from the school one of the air monitors provided by DoE.
    
2. Ask the staff member to place the air monitor around their work area several times each day, for two to three days.
   
   This will allow for the differing variables that affect the amount of air particles in the space to be considered in the assessment of the area, including number of people and the amount of talking.
    
3. Ensure the staff member records the date/time, monitor readings and location of the monitor as it’s moved around the classroom/workspace over the course of the two to three days.
   
   Sample template:

Date/time          Monitor reading             Monitor location

__________          ________________             _________________

CO2 risk rating

Diagram two will assist in making a risk assessment of the CO2 monitor readings, which measure the carbon dioxide parts per million (ppm) within the space. Note these measurements are based on the presumption mask wearing is occurring to assist in managing the level of risk.

Diagram two:⁴

Risk mitigation

At the end of the monitoring period if the carbon dioxide readings are within the high relative risk range, then immediate measures must be taken to improve the air flow to enable new outside air to flow into the area, either mechanically or naturally. If readings are within the upper moderate relative risk range, work to improve indoor air quality. If possible, use the air monitor again for a further two to three days to ensure the new measures are effective in reducing the carbon dioxide ppm.

If the air flow cannot be improved or the workspace/classroom cannot implement any of the measures outlined in the DoE documents: Understand Ventilation Requirements for your School and the Ventilation Sticker System, the room needs a HEPA filter air purifier. These are provided to worksites by the DoE.

Support

If you are having issues with any part of this advice, follow the Occupational Safety and Health Issue Resolution Process as outlined in the DoE health and safety policy/procedures⁵.

Please also liaise with your school organiser and/or the WHS organiser at the SSTUWA if you need to enact this process to resolve ventilation risks at your school. Reach them at (08) 9210 6000 or contact@sstuwa.org.au

¹Safe Indoor Air (Ventilation) Recommendations, OzSage, 6/9/21

²https://ikon.education.wa.edu.au/-/understand-ventilation-requirements-for-your-school/

³Guidance Document for Primary and Secondary Schools: COVID-19 Ventilation Optimisation, Brad Prezant, 17/11/21

⁴Safe Indoor Air (Ventilation) Recommendations, OzSage, 6/9/21

⁵Occupational Safety and Health Procedures (D18/0019186), DoE, 16/4/19.