As with many questions about COVID-19, there are at least some self-described experts on both sides of the debate over the impact of air conditioning in public buildings. On the one hand, there is a widely cited Chinese study that purports to document the transmission of the virus in an air-conditioned restaurant. It concluded that the horizontal flow of cold air spread the virus a considerable distance from an infected person and caused infections among downwind customers. However, many others have raised doubts about this finding and have also questioned the extent of its relevance to the more sophisticated air conditioning systems used in most American buildings.
On the other hand, the arguments in favor of air conditioning are more convincing. Most significantly, it can ventilate as well as cool, replacing potentially contaminated indoor air with an influx of safer outdoor air. These systems also have filters that can capture at least some virus-containing particles. In addition, the air flow pattern from an air conditioning system can be designed so as to minimize the risk of spreading disease from person to person. These are among the conclusions of a recent position paper put out by the American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE). However, ASHRAE notes that much depends on choosing the right equipment as well as proper installation, operation, and maintenance.
Of course, one can’t look at COVID-19 risks in isolation. Air conditioning has substantial and well documented health benefits in its own right. One study estimates that its widespread use in the U.S. has prevented 18,000 heat-related deaths annually.
Despite these benefits, air conditioning has become politically incorrect in some circles. In recent years, the onset of summer brings with it opinion pieces decrying air conditioning’s contribution to climate change (because of its high electricity use) and other ills. Doubtless, the critics will try to tag air conditioning as a COVID-19 facilitator, but it’s a good thing they are wrong, since most of us consider it a summertime necessity and will continue demanding it regardless.
Of course, air conditioning’s virus-fighting role can be improved. Ventilation rates can be increased and filtration can be enhanced to capture more of the smaller virus particles and not just the larger bacteria and dust-sized ones. But these goals are best met not by more federal interference but by less.
At a minimum, Congress should reject pending bills restricting the refrigerants used in most existing systems on the grounds that they contribute to climate change. These bills, which not surprisingly are supported by the makers of pricey “greenhouse friendly” substitute compounds, would raise the cost of air conditioning without doing anything to improve virus protection. Hopefully, the seriousness of the coronavirus pandemic helps put an end to this rent-seeking.
Further, the federal government’s overemphasis on energy efficiency could be a roadblock to improving ventilation and filtration. Both are energy users, so beefing up protection against the indoor spread of coronavirus is going to require more energy use than making no effort at all.
However, there are many “green building” activists who arguably added to the vulnerability by prioritizing energy efficiency and climate change advocacy over indoor air quality, and they have successfully lobbied for federal programs reflecting these priorities. The result has been tighter buildings that may hold in more virus particles, including systems that cut back on ventilation to save energy. Many of these organizations are now requesting subsidies from Congress to do more of the same.
ASHRAE has also been a proponent of the efficiency and climate agenda, though it has pursued it in a more balanced manner than the activists—one that doesn’t ignore indoor air quality or treat it as minor concern. In response to COVID-19, ASHRAE now recommends disabling or bypassing certain energy-saving devices that reduce the influx of outdoor air—including ones that had been incentivized by federal tax breaks and other measures—as well as upgrading the filters. It also suggests running air conditioning systems for longer hours (“24/7 if possible”) to maximize the benefits. The Centers for Disease Control and Prevention largely concurs. This is a good start towards a rebalancing of priorities.
The use-less-energy absolutism that has dominated federal policy needs to be reconsidered in light of COVID-19. At the very least, the federal government should refrain from adopting any air conditioning-related measures that place energy efficiency and climate goals ahead of coronavirus protection.
Whatever the future of COVID-19, few Americans are willing to endure summer without air conditioning, neither in their homes and offices nor in the restaurants, gyms, shops, places of worship, and other establishments they enter. Nor should they, even in a post-coronavirus world, since it will continue to enhance public health so long as federal policy doesn’t get in the way.