Toronto·State of Our Schools

Even with upgrades and extra filters, classrooms aren't getting equal air quality, experts say

Some experts say not all students are receiving the same level of protection against COVID-19 with the current ventilation systems and upgrades installed in schools.

Part 2 of our CBC series on the state of TDSB schools focuses on ventilation in classrooms

Isabel Meana stands in front of her school, Runnymede Junior and Senior Public, on Aug. 27, 2021. (Angelina King/ CBC)

Although Isabel Meana was sad to see her summer holidays end, the sixth grader was excited to be heading back to Runnymede Junior and Senior Public School for a few reasons — including air conditioning.

Being in Grade 6 means she'll spend more time in the newer part of the school, which has better ventilation. In previous years, she spent most of her day in the original building, which was built in 1915, where she says the heating is erratic.

"In the winter it's usually pretty cold. But we have to keep the windows open because we have to have air circulation because of COVID," she said. "Some people wear their jackets [inside] … but we would get really hot in the summer."

Her mom Erin Meana says she loves the staff at Runnymede, but the condition of the building makes it more challenging for kids to learn. 

"They just don't have proper learning conditions in their schools. It's too hot. It's too cold. The bathroom facilities are awful," she said. 

Meana, an architect, and a member of the non-partisan advocacy group Fix Our Schools, says she had concerns about ventilation and the deterioration of Ontario schools long before the pandemic and notes Runnymede's mechanical ventilation system is a series of separate systems that should be integrated into one. Parts of the ventilation system are on the school's list of repairs.

"The kids today, they don't even know what a good condition looks like at their school. And it's hard to watch."

Runnymede's original building opened in 1915, according to the TDSB. (Angelina King/ CBC)

Toronto students returned to classrooms last week amid Ontario's fourth pandemic wave and for many are going back to schools in serious need of repair. School boards across the province are dealing with a combined $16.8-billion repair backlog, more than 25 per cent of which is at Toronto schools.

The pandemic has focused the public's attention on the state of disrepair in schools, specifically ventilation. Some experts say when it comes to air quality, not all students are receiving the same level of protection against COVID-19 with the current ventilation systems and upgrades that have been installed.

The repair backlog at the Toronto District School Board (TDSB) now sits at $3.7 billion. The board has 314 projects underway that include ventilation-related improvements and replacing windows. 

The provincial government says over the last year, it spent $600 million to improve ventilation in every school in Ontario.

In an interview with CBC's Metro Morning last Thursday, Education Minister Stephen Lecce said the majority of the money went to 2,000 structural ventilation improvements and the province also put 70,000 standalone HEPA  units — medical-grade filters with fans that purify air — into classrooms, .   

"That is a big difference when you look at the overall state of air ventilation quality within Ontario schools," Lecce said.

What's being done to improve air quality?

In Toronto, the two largest school boards have put a standalone HEPA filter in each classroom.

That goes above the Ministry of Education's guidance, which says schools should put a HEPA filter in classrooms and spaces that don't have mechanical ventilation. HEPA filters are also required in all full-day kindergarten classrooms, regardless of what ventilation system the school uses. 

There are three types of ventilation systems in schools: mechanical, partial mechanical and natural ventilation, which means a school relies on opening windows. 

This new HEPA air filtration system was shown to parents when Toronto District School Board staff gave a tour of Highland Heights Junior Public School on Aug. 10, 2021 as families prepared to return to in-class learning in the fall. (Evan Mitsui/CBC)

Mechanical ventilation systems use fans and HVAC systems to bring outdoor air into a space and push contaminated air out. Many schools have partial mechanical ventilation systems due to newer wings or buildings being added to older ones. 

The province is directing schools with mechanical ventilation systems to use the highest-grade filters possible, change filters more frequently, calibrate systems for maximum fresh air intake and run ventilation systems for two hours before and after school hours.   

The education ministry also says all Ontario school boards should post on their websites the type of ventilation a specific school has and how many HEPA filters are in place. 

Click on your school board below to view the downloadable file:

HEPA filters are noisy and the TDSB says they must be run at high speed first thing in the morning, but can be turned down later in the day.

Energy engineer David Elfstrom says turning down the filter isn't as safe and compares it to closing an open window to a little crack.

"It turns it into filtration theatre," he said. 

'There is huge inequity'

In Toronto, at least 99 public schools have no mechanical system and rely on windows alone, and 58 of them are with the TDSB.  

"There is huge inequity," said Colin Furness, an infection control epidemiologist.

He says air quality audits should have been performed in every classroom in the province over the summer to create an informed and equitable approach to ventilation.

"Some classrooms may have more than what they need. And many, of course, may not have what they need," Furness said.

Furness and Elfstrom say putting a HEPA filter in every classroom still leads to inequity in ventilation: one filter in a naturally-ventilated classroom will not lead to the same air quality as one in a mechanically-ventilated room.

Students at Runnymede Junior and Senior Public School say windows have been left open during the pandemic to increase air flow. (Michael Charles Cole/CBC)

"You need a whole bunch of portable HEPA filters to achieve the same as what an existing mechanical system would do with upgraded filters," said Elfstrom, who is calling for a uniform air quality standard for all the province's schools.

The TDSB says its HEPA units can complete two air exchanges per hour in an average-sized classroom. Elfstrom recommends six.

The board says the use of HEPA filters combined with "improved improved ventilation strategies and existing health and safety protocols" will work together to reduce the risk of COVID-19 transmission.

Meanwhile, Isabel Meana's mom says Fix Our Schools has been pushing for air quality and other standards in Ontario schools long before COVID.

"There are quality and condition standards in almost every workplace. This is not only a workplace, but with children," Erin Meana said.


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