Manitoba school ventilation projects may not purify the air of COVID-19, expert says
Jeffrey Siegel says he is frustrated when cost concerns dominate the discussion about improving ventilation in schools during the fourth wave of the COVID-19 pandemic.
“Every dollar that Manitoba doesn’t spend on improving schools, you pay for it in other ways down the road,” said Siegel, professor in the Department of Civil and Mineral Engineering at the University of Toronto and an expert on the quality of indoor air.
Manitoba has issued guidelines for ventilation in schools and has committed tens of millions of dollars to more than a dozen ventilation-related projects across the province – but Siegel says that may not be enough.
Since the start of the pandemic, doctors, teachers and parents have called on the province to take action to improve ventilation and filtration in schools to reduce the risk of transmission of COVID-19.
The Manitoba government has committed to funding ventilation and filtration projects in 14 schools, worth a total of $ 20.4 million, by the summer of 2023, with an additional $ 40 million going to schools. school divisions for further health and safety improvements.
This level of funding and the number of projects “may not be adequate” in a province with more than 800 schools, Siegel said.
It may also fall short of efforts in other jurisdictions such as Ontario and cities like Vancouver, which have completed or are in the process of upgrading air systems in all schools.
Funding can be used for ventilation improvements: province
The Ontario government has pledged $ 600 million specifically to improve ventilation in schools.
Ontario Education Minister Stephen Lecce said all 72 publicly funded school boards have installed stand-alone High Efficiency Particulate Air (HEPA) filters in all classrooms without ventilation systems mechanical, The Canadian Press reported earlier this month.
Ontario has deployed 20,000 HEPA units to all kindergarten classrooms, even those that are mechanically ventilated.
Manitoba’s spending on individual projects ranges from $ 130,000 to $ 2.6 million. Funding is intended for projects such as upgrading heating, ventilation and air conditioning (HVAC) systems and air handling units.
Three of those projects have been completed and three more are expected to be completed this year, according to the province. The rest is expected to be completed by summer 2023.
A government spokesperson said the province has also committed $ 40 million of the $ 58 million of the 2021/22 Safe Schools Fund to school divisions on a per student basis to support a range of initiatives in health and well-being.
“Since addressing ventilation issues is one of the health and safety measures, this funding can be used by school divisions to pay for ventilation costs,” the spokesperson said.
Manitoba’s guidelines for how schools should use their ventilation systems are based on recommendations from the American Society of Heating, Refrigeration and Air-conditioning Engineers (ASHRAE).
Provincial guidelines do not specifically address the use of portable HEPA filters in rooms without mechanical ventilation, but recommend that schools not use these rooms or find “a technical solution.”
They are also asking schools to purge the air from their buildings every day for two hours before and after occupancy.
Renovating old buildings with centralized mechanical ventilation systems can be invasive, “much like doing a lung transplant,” says Siegel.
This is why many schools may choose to use portable HEPA units or use natural ventilation.
The chair of the ASHRAE Outbreaks Task Force says HEPA filters are a cost-effective way to get the amount of air needed to reduce aerosol transmission.
“Just basic air purifiers – they don’t have to be high tech settings. HEPA filters work fairly well and have been tested and accepted by the healthcare community for decades. “said Bill Bahnfleth, a mechanical engineer with expertise in bio. -control of aerosols.
Prioritize ventilation in plans, according to group
In British Columbia, officials say HVAC systems in all schools in the Vancouver School District now feature the high-end MERV-13 filters (MERV stands for “minimum efficiency ratio value”) recommended by ASHRAE, according to the Canadian Press report of September 8.
In Calgary, HVAC systems in schools are configured to maximize outdoor air intake, CP said.
In places with extreme climates like Manitoba, Bahnfleth says improving filter efficiency may be more cost effective than increasing ventilation, which requires heating or cooling the air to meet temperature and temperature standards. indoor humidity.
Manitoba guidelines do not specify any minimum standards for filtration, recommending that schools have HVAC systems professionally inspected and adjusted to maximize the supply of fresh air.
Schools should ensure that they have the “highest level of air filtration allowed” in the operating recommendations for their HVAC systems, as directed.
Lauren Hope, a Winnipeg teacher and activist with advocacy group Safe September, says the province and Manitoba school divisions must prioritize ventilation improvements in their efforts to mitigate the spread of COVID-19 this fall.
“This mitigation is very costly, if we look at it in terms of updating ventilation systems, especially in the Winnipeg School Division, which has the most dated ventilation systems of any division in the province, simply because it is an older part of town. she said.
“What we really need is the ability to open the windows. We need to move lunches and all the food we can outside as much as possible, and then we need to have… filtration. “
The Winnipeg School Division says it follows all public health guidelines, which emphasize mechanical ventilation as the preferred strategy for indoor air quality.
The division “optimizes existing ventilation systems to maximize outdoor air,” spokesman Radean Carter said in an emailed statement.
She said the division’s existing HVAC systems allow schools to maintain adequate fresh air levels and that “HEPA classroom air filters are not necessary.”
A provincial government spokesperson said the 14 schools benefiting from a ventilation system upgrade were selected using a framework that prioritizes health and safety.
Siegel says social equity should also be a criterion for prioritizing projects.
“We know that people who are racialized or marginalized or of lower socioeconomic status have been exposed to worse air pollution, and it really affects their health,” he said.
Provinces must act now to improve air quality in schools, he said, raising fears that a possible fifth wave of the pandemic could strike at the same time as the regular flu season.
“It could mean the difference between schools being able to stay open… until late fall when things could get a little gloomy.”