As the pandemic enters a new phase in the United States marked by fewer precautions and the rise of the even more transmissible BA.2 subvariant of Omicron, the Biden administration has begun to stress the importance of mitigate the risk of indoor aerosol transmission, the main driver of the pandemic.
The Environmental Protection Agency recently released expert advice for building managers, contractors and business owners, with two pages of recommendations that codify best practices on ventilation, air filtration, and air disinfection from university experts and federal agencies for the past two years. The agency said the implementation could be funded with federal funds from the $1.9 trillion U.S. bailout package, which President Biden signed into law a year ago.
Alondra Nelson, head of the White House Office of Science and Technology Policy, said last week that the guidance was part of an initiative called the Clean Air in Buildings Challenge. In a blog post titled “Let’s clear the air on Covid‘, she quoted the advice and said: ‘Now we all need to work collectively to let our friends, family, neighbors and co-workers know what we can do or ask to make it safer to be together. on the inside.
“For decades, Americans have demanded that clean water flow from our faucets and that pollution limits be placed on our chimneys and tailpipes,” Dr Nelson wrote in the post. “It is time that healthy and clean indoor air also became an expectation for all of us.”
US federal health officials were initially slow to identify airborne transmission of the virus. It was not until October 2020 that the Centers for Disease Control and Prevention acknowledged that the virus can sometimes be airborne, long after many infectious disease experts warned that the coronavirus travels aloft in small airborne particles. Scientists have been calling for more focus on tackling this risk for more than a year.
The initiative is “really a big deal,” said William Bahnfleth, a professor of architectural engineering at Pennsylvania State University and head of the outbreak task force at the American Society of Heating, Refrigerating and Air. -Conditioning Engineers. “It’s the start that is often the hardest part.”
The company, whose roots date back to the dawn of the skyscraper in the late 19th century, is a global, not-for-profit technical society that, among other things, develops the consensus indoor air quality standards referenced in the US building codes.
Dr. Bahnfleth’s task force was created as the pandemic began to sweep the world in March 2020, and the new federal recommendations closely follow its guidance. He said the pandemic had given impetus to the long-awaited campaign to improve the country’s “poor” air quality standards for buildings, noting that existing standards had failed to protect people from coronavirus infections.
Viruses can travel in different ways. At the start of the pandemic, health officials assumed that the coronavirus was mainly transmitted by droplets expelled during coughing or sneezing, as is the case with influenza, or possibly by contact with surfaces. contaminated. But many scientists noted growing evidence that the coronavirus was airborne, spreading as tiny drifting particles in indoor spaces.
Similar to the rating system for high-quality masks, whose high-tech filter material traps at least 94-95% of the most dangerous particles (N95, KN95 and KF94), filters used in building ventilation systems have this which is called a MERV Ranking. The higher the score, which ranges from 1 to 16, the better the filter is at trapping particles.
New federal guidelines advise buildings to upgrade to at least a MERV 13 filter, which traps 85% or more of risk particles. Before the pandemic, many buildings used MERV 8 filters, which are not designed for infection control.
Long before the pandemic, studies have shown that indoor air quality affects the health of students and workers. A Harvard study of more than 3,000 workers showed that sick leave increased by 53% among employees working in poorly ventilated areas. Better ventilation has also been associated with better test scores and less school absenteeism.
“Improving indoor air has benefits beyond Covid-19,” Dr Nelson wrote. “It will reduce the risk of catching the flu, a cold, or other airborne illnesses, and lead to better overall health outcomes.”
March 27, 2022
Due to an editing error, an earlier version of this article misrepresented the amount of the US bailout President Biden signed into law last year. It was $1.9 trillion, not $1.9 billion.