While you weren’t paying attention to local news yesterday, Chicago Public Schools announced they are spending $8.5 million to put an air purifier in each of their 20,000 classrooms. The district conducted its own inspection to ensure every classroom had access to either a working window or mechanically ventilated air supply and exhaust.
So here’s the filter I’m using to examine this information. I’ve been aware of deferred HVAC maintenance as a problem in public schools, both nationally and in Chicago, for many years. “Sick building syndrome” — when indoor air quality is so bad it aggravates children’s asthma or causes other breathing problems — has been a problem since well before the pandemic. The issue now takes on heightened importance, and a June report from the U.S. Government Accountability Office (GAO) says that one-third of schools nationally need HVAC upgrades.
From what the district has said, it didn’t really check out the quality of the HVAC systems supplying that mechanically ventilated air. Upgrading those HVAC systems is expensive. It’s a lot cheaper to put in an air purifier. But experts suggest that when you’re looking for a solution to the tough problem of how to stop Covid from spreading in a classroom, air purifiers are actually more of a “meh” solution.
The Best Fix for Air Quality Costs Big Bucks
A recent article in Education Week sifted through the possible ways to improve classroom air quality, a key factor in deciding whether it’s safe to return to school buildings. Mark Benden, an ergonomics expert at the Texas A & M School of Public Health, recommends that schools have strong filters (MERV-13 or higher– a much stronger filter than most people’s home furnace filters) in their HVAC systems. But many schools don’t have HVAC systems that can handle that strong a filter.
Long before the pandemic hit, many public school systems were dealing with old buildings and deferred maintenance on big-ticket items like upgrading their HVAC systems. In Chicago, the biggest effort to improve HVAC in recent years was Mayor Rahm Emanuel’s push for window air conditioning units in more than 200 schools. Now, they are facing more expenses and less state tax revenue to help pay them.
So, upgrading HVAC systems to handle stronger filters–the best solution–is not going to happen in most CPS buildings. Note: newer, LEED-certified CPS schools should be able to handle this level of filtration. If your child attends a newer school, the building should be in good shape and should be using those high filters. But if you are in an older CPS building, you’re relying solely on those air purifiers, the fallback solution.
Are Air Purifiers Good Enough? It Depends.
If air purifiers in every classroom are the experts fall-back solution, does that mean they are good enough? Maybe. Speaking personally, that’s exactly what the private school where I moved my own daughter this year is doing. But the middle school students have only been indoors a few times. When they were inside, it was for only a few hours at a time, not the entire school day. In fact, the middle school students are fully remote now through the spring. Parents do not want to take chances with older kids.
Meanwhile, CPS may not be testing what we really need to know to determine the effectiveness of air purifiers. Environmental engineering firm Carnow Conibear‘s inspections couldn’t really answer the most important questions about carbon dioxide levels or potential viral transmission. No one was in the building when they inspected.
Given all this, here’s where I land: if I were the parent of a preschooler, I would probably go ahead and send them back to school. (If that’s even possible this month, given spiking community spread.) But if I were the parent of a child in a special education cluster program, I would really think hard about that child’s particular health history and issues before deciding to take the risk. And I’d feel much better if my child were in a LEED-certified building.
One last thought–if this is all they can afford to do, why didn’t they just do it back in the summer and have them ready when school started?