Americans spend, on average, 90 percent of their time indoors. And like the water we drink, the quality of the air we breathe can significantly impact our health. For the general public, this issue came into sharp focus in 2020, when COVID-19 proved to spread far more easily in spaces without proper ventilation. Since then, experts and policymakers have pushed for updated standards for indoor air quality in buildings. Last year, the Biden-Harris Administration — along with the EPA CDC, and other federal agencies — introduced a new initiative, the Clean Air in Buildings Challenge, to prompt building owners to evaluate and upgrade their HVAC systems. And in June 2023, leading global HVAC&R society, ASHRAE, expects to publish a new standard with requirements for infection risk mitigation in existing and new buildings.
This new standard is meant to mitigate the spread of respiratory diseases within indoor spaces, but studies show that poor indoor air quality can affect overall health, too. The EPA reports that concentrations of some pollutants can be two to five times higher inside than out — a significant factor for those who suffer from allergies and asthma. Studies also show that indoor air quality can have an impact on brain health and cognitive performance. For example, recent research conducted by the Harvard T.H. Chan School of Public Health showed that office environments with higher air pollution and lower ventilation rates were associated with slower response times and reduced accuracy on cognitive tests.
A Higher Bar
William P. Bahnfleth, Ph.D., PE, a mechanical engineer and professor of architectural engineering at Pennsylvania State University, consults on energy efficiency and indoor air quality in buildings, among other areas. Typically, Bahnfleth finds himself unimpressed with the indoor environments at the hotels and venues he frequents for academic conferences, including the air quality. He’s noticed that when colleagues have CO2 (carbon dioxide) monitors on hand, which can indicate how much fresh air is circulating, the results often have been “surprisingly high.” To Bahnfleth, that suggests issues with the design of the space or lack of maintenance.
“Why should those who put on conferences care?” he asked. “Because, at least for a while, the conference-attending public is really concerned about the quality of these public environments that they go into, in a way that they haven’t been in the past.”
One barrier to better air quality is that regulation is nearly nonexistent for indoor air quality in existing buildings — raising the standards has typically required an owner or manager to be proactive, Bahnfleth said. But he thinks that may soon change. Much like the energy report cards that New York City has begun requiring for buildings larger than 25,000 square feet, an assessment and disclosure of a building’s air quality may not be too far off, Bahnfleth said. If indoor air quality “follows the pattern that we’ve seen with energy efficiency,” he said, “we will move from just having design standards to having requirements for operation that eventually may have regulatory teeth.” In the U.S., that would most likely mean states and municipalities would adopt and enforce those regulations.
Bahnfleth currently serves as chair of the ASHRAE committee tasked with coming up with the new infection risk mitigation standard that better reflects public health needs — globally, commercial and public buildings reference ASHRAE standards to plan future construction and ongoing maintenance. The goal, he said, is for the new standards to provide strategies for maintaining a higher level of indoor air quality that won’t adversely impact a building’s energy efficiency and operating costs.
“What ASHRAE is trying to do right now is come up with a target,” said Meghan McNulty, PE, LEED AP O+M, senior project engineer for engineering consultancy Servidyne. She frequently consults with buildings on how to increase energy efficiency and indoor air quality, and like Bahnfleth, she is a member of ASHRAE. “That’s been the challenge — how much is enough? When do I stop?” McNulty said. “That’s what this new standard is going to try to help define.”
Bahnfleth emphasizes that the new standards won’t necessarily require buildings to overhaul their entire HVAC system, but rather make upgrades when and where appropriate — like providing portable air cleaners, HEPA filters, and UV lights during flu season, for example. “My hope for the future is not that we’ll operate all buildings like airborne infection isolation rooms all the time, but that we will be prepared to increase the level of protection when there is actually a reason to do it,” he said. “Otherwise, we’re going to be wasting a lot of energy and accomplishing not much with it.”
An Organizer’s Checklist
“There’s no enforcement for indoor air quality building codes like there is for fire codes,” McNulty said. “So your interest in the indoor air quality of the venue — that becomes the enforcement.” McNulty serves on an ASHRAE host committee that helped plan a recent conference, and she shared tips for planners on how to ensure that a building’s indoor air quality is up to an acceptable standard for a meeting or event.
- Start by having a conversation with the venue and let them know that indoor air quality is important to you and your group. McNulty emphasizes that you don’t have to be an HVAC engineer to have a conversation about indoor air quality. She advises asking general questions about the venue’s approach to indoor air quality to gauge their level of commitment — like, “What are their plans? Do they have a program in place? What kind of maintenance do they do? How do they monitor the HVAC system to ensure it’s working during events? If they stare at you blankly,” she added, “that’s not a good sign.”
- Ask if the building’s ventilation system is in compliance with the most current ASHRAE Standard 62.1-2022, Ventilation and Acceptable Indoor Air Quality, the minimum standard for commercial buildings, which requires that ventilation be checked and measured every five years. Also ask when ventilation air will be provided, to ensure that their schedule matches your event schedule — venue operators “can make sure the appropriate equipment is on and running continuously when you have people in those spaces,” McNulty said.
- Filtration is another important topic worth asking about. McNulty said the minimum- rated filter a building should use is MERV 8 — “which protects the equipment, but it doesn’t grab the tiniest particles that matter for our health,” she said. To achieve that, the ASHRAE Epidemic Task Force recommends high-efficiency filters rated MERV 13 or higher to remove virus-laden particles. You should also ask how often they change their filters.
Jennifer N. Dienst is senior editor at Convene.