The White House’s roadmap for the next phase of the pandemic covers all the usual suspects, including Covid-19 surveillance, testing, vaccination and treatment. But there’s also a happy surprise tucked in there: a series of proposals to help improve indoor air quality.
This marks an essential shift toward acknowledging that cleaning the air can help mitigate the spread of Covid. “It’s overdue,” says Virginia Tech engineering professor Linsey Marr.
Under the proposal, the Environmental Protection Agency is to create a clean air checklist that recommends steps to filter air and increase the supply of fresh outdoor air in buildings of all kinds. A new rating system for building ventilation and filtration, akin to sustainability certifications such as LEED, is to be developed. And government agencies would be tasked with increasing the public’s understanding of air hygiene and how it can reduce Covid transmission.
These are good ideas that will foster awareness about the need to keep indoor air fresh and clean. But the administration could go further. So could companies, businesses and schools.
Air hygiene took a backseat for much of the pandemic as we focused on medical and social interventions such as vaccines, treatments, testing and masks. Those have been critical but often divisive, because they have involved persuading individuals to act for the greater good. Improving indoor air quality, on the other hand, is an innocuous way to improve health outcomes now and well beyond the pandemic. “You’re not cleaning surfaces, you’re not telling someone to wear a mask,” says Joseph Allen, a professor at Harvard’s T. H. Chan School of Public Health. “It’s operating all the time in the background.”
Part of the difficulty in carrying out this change is the large menu of options for improving ventilation and filtration, including some that don’t work. Different buildings have different needs, and people have struggled to sift through the complexity.
We’ve seen how efforts at improvement can go wrong. Some schools that used money from the American Rescue Plan to try to improve ventilation wasted it. And it’s no wonder they struggled. Products like plasma sterilizers or ionizing purifiers made lofty, unsubstantiated claims. And some classrooms went all in on plexiglass dividers, which in almost all situations actually hinder ventilation, Marr says.
In the past year, Kim Prather, an aerosols expert at University of California, San Diego, who has been helping schools correct their mistakes, says that without more money, many schools simply can’t afford to make substantive improvements to ventilation and filtration. Overhauling older HVAC systems, or buying portable air filters for every room is expensive.
Yet the investment is worthwhile because it can reduce the spread of respiratory viruses of all kinds. Researchers have amassed plenty of case reports suggesting that ventilation and filtration can prevent superspreading events. Several ongoing and planned studies will give better information on the value of specific ventilation improvements for different settings.
A University of Leeds study of 30 primary schools in northern England, for example, will compare various approaches to ventilation and filtration, whether simply opening windows, incorporating air filtration or using ultraviolet disinfection devices.
A similar study underway in the US will focus on how ventilation can affect flu infections. Donald Milton, an environmental health expert at University of Maryland, and his team will put people with flu symptoms (who should be shedding a lot of virus) in rooms outfitted with differing methods of air-cleaning to see how they affect virus transmission to others.
Lockdowns and masks have given most people a two-year reprieve from the worst of the flu, but infection rates will surely creep back up once people have returned to regular routines.
And everywhere, but especially in schools, seasons will play a role. A Canadian study showed that hospitalizations in children with asthma increase like clockwork about 18 days after Labor Day. That’s peak ragweed season, but it’s also when kids are back together and mingling with all the other little viral vectors. When they do so in stagnant, unfiltered classroom air, viruses spread easily.
Clean air is not a panacea. Infected, maskless people can still transmit virus particles to others near them. But this passive measure could reduce incidences of many respiratory infections, and have other long-term health benefits.
Congress should ensure that Biden’s plan gets the funding it needs to take the first small steps toward improving indoor air quality, and make it a more prominent part of the nation’s Covid mitigation strategy. School districts should consider investing some of their unspent Covid relief funds on effective upgrades. They should also follow the Boston Public School system’s lead by monitoring indoor air quality in schools and making those measurements public.
As people return to spending many of their waking hours in offices, states should create incentives for businesses to improve ventilation and openly share air quality measurements with their employees.
We take for granted the clean water flowing from our taps, and government oversight of the outdoor air we breathe. Having experienced two years of Covid-19, we should have learned enough to demand better indoor air quality, too.
Bloomberg
