A ventilation expert enlisted by a group of worried NYC school teachers believes the DOE is not doing enough to prevent the spread of COVID-19 in school buildings when students return on September 21st.

Monona Rossol, an industrial hygienist and chemist who assesses workplace safety, held a virtual training session on Tuesday with roughly 100 members of the MORE-UFT caucus, a group that's been largely opposed the reopening of schools, arguing they’re simply not safe to reopen during the pandemic.

Rossol bluntly asserted that the school ventilation reports released by the city Department of Education and United Federation of Teachers union "are for shit" because they fail to provide specific information when it comes to proper ventilation, offering only vague responses. She contends the standards DOE inspectors follow to determine air quality, as outlined by the American Society of Heating and Air-Conditioning Engineers [ASHRAE], are inadequate.

"They say, 'Well, you know, all you need is a little open window, a little fresh air, and people will survive' and that's very true" in most cases, said Rossol. "But they won't survive this bug because this bug is a contaminant that is very small and is created in the space. So if you recirculate the air...you're just running the damn stuff around the building. It's just a really bad system; we have to literally walk away from the ASHRAE standard."

Referring to the speed at which air is replaced in a room, Rossol said school staff and administrators "have to know what the air exchanges per hour are. They have to know what the MERV filter is--what number it is--and they have to know the percent of fresh air."

Rossol believes the DOE should upgrade schools with air filtration systems that are equivalent to what hospitals use. MERV filters with a higher rating, at least 13 or more, should also be installed, as Governor Andrew Cuomo has mandated for the reopening of shopping malls.

The School Construction Authority has said that MERV-13 filters have been installed at some schools, but has not said how many have them.

"You have to bring in enough fresh air and you have to change it rapidly enough that if you've got a spreader in that room. It's not going to take two hours before that air is completely replaced," said Rossol. "The ideal is six room exchanges an hour and a HEPA filter, which is a MERV-17 and at least 20% fresh air. We know they'll do about 90-95% risk reduction."

The presentation was eye-opening for Matthew Driscoll, a teacher at the Clinton School in Union Square and UFT chapter leader.

"After that presentation, it seems like the way [HVAC systems are] designed, even the newer ones [are] more to prevent pollutants from outside coming in from cleaning the air inside of indoor pollutants, including viruses or other illnesses, other basic illness," said Driscoll, who's uncertain over whether his school is really safe because the UFT and DOE's own ventilation reports are vague.

"I feel like teachers are not able to even make a decision, because we don't know what the state of ventilation really is in any schools without detailed reports that go a lot further than what the DOE has provided," said Driscoll.

The news comes amid growing concerns from teachers about their safety, with some refusing to set foot in school buildings. In Queens, teachers at IS 230 stood outside their school building in Jackson Heights to demonstrate their lack of confidence in the building's safety.

"We saw the procedures supposedly put in place to keep us safe not actually keeping us safe,” Lysette Latorre, a special education teacher at the school told the Daily News. “We were promised it would be different this time around … and it hit close to home for us because we already lost a staff member."

The DOE initially identified ten school buildings that are not safe for reopening, including the Martin Luther King Jr. Educational Complex in the Upper West Side. There, the windowless school had improper ventilation, according to an independent ventilation expert. The school had been among 30 schools inspected by experts hired by the UFT in August, coinciding with the DOE's plan to dispatch School Ventilation Action Teams to 1,600 school buildings across the system. (Five of those schools have since been given the green light by the DOE.)

The DOE and Mayor Bill de Blasio have continued to assure educators that the majority of classrooms are safe to occupy.

"And what we can say today is 96% of those classrooms have passed and are ready to go," de Blasio said at a news conference on Tuesday. "Work will continue on the classrooms that need a little more to be done before school opens. There's time, obviously, to make the improvements before school."

Rossol, however, said any teacher in a room with inadequate ventilation should simply leave.

"They just need to get the fuck out of there," said Rossol. "Let's just get real -- an open window is not gonna cut it."