With the pandemic entering a new phase in the United States marked by fewer precautions and the rise of even more communicable Omicron subvariant BA.2the Biden administration has begun to emphasize the importance of mitigating the risk of indoor aerosol transmission, the main driver of the pandemic.
The Environmental Protection Agency recently issued an expert guide for building managers, contractors, and business owners, with two pages of recommendations that codify best practices on air ventilation, filtration, and disinfection from academic experts and federal agencies for the past two years. The agency said the implementation could be financed with federal funds from the US $1.9 trillion bailout planthat President Biden enacted the 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 Covidthe guide quoted, saying, “Now, we all need to work collectively to make our friends, family, neighbors and co-workers aware of what we can do or ask to make it safer to be indoors together.”
“For decades, Americans have demanded that clean water flow from our taps and that pollution limits be placed in our smokestacks and exhaust pipes,” Dr. Nelson wrote in the post. “It is time that healthy and clean indoor air also becomes an expectation for all of us.”
US federal health authorities were initially slow to identify airborne transmission of the virus. It was only in October 2020 that the Centers for Disease Control and Prevention recognized that the virus can sometimes be airborne, long after many infectious disease experts warned that the coronavirus traveled in the air in tiny particles. Scientists have been calling for a greater approach to address that risk. for more than a year.
The initiative is “a really big deal,” said William Bahnfleth, a professor of architectural engineering at Pennsylvania State University and head of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers’ Task Force on Epidemics. “Getting started is usually the hardest part.”
The society, whose roots go back to the dawn of skyscrapers in the late 19th century, is a nonprofit global technical society that, among other things, develops the indoor air quality consensus standards referenced in US building codes
Dr. Bahnfleth’s task force was created when the pandemic began sweeping the globe in March 2020, and new federal recommendations closely follow its guidance. He said the pandemic had given impetus to a long-awaited campaign to improve the country’s “lackluster” air quality standards for buildings, noting that existing standards had failed to protect people from coronavirus infections.
Viruses can travel in a variety of ways. Early in the pandemic, health officials assumed the coronavirus was spread primarily through droplets expelled by coughing or sneezing, as is the case with the flu, or perhaps through contact with contaminated surfaces. But many scientists noted mounting evidence that the coronavirus was airborne, spreading in small particles drifting indoors.
Similar to the rating system for high quality maskswhose high-tech filter material traps at least 94 to 95 percent of the most dangerous particles (N95, KN95 and KF94), the filters used in building ventilation systems have what is known as MERV Rating. The higher the rating, which ranges from 1 to 16, the better the filter will be at trapping particles.
The new federal guidelines advise that buildings be retrofitted with at least a MERV 13 filter, which traps 85 percent or more of hazardous particles. Before the pandemic, many buildings used MERV 8 filters, which are not designed for infection control.
Long before the pandemic, studies showed 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 percent among employees in poorly ventilated areas. Improved ventilation has also been associated with better test scores and fewer school absences.
“Improving indoor air has benefits beyond Covid-19,” Dr. Nelson wrote. “It will reduce the risk of getting the flu, a common 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 American Bailout that President Biden signed into law last year. It was $1.9 trillion, not $1.9 billion.