Air conditioning upgrades are a top priority for landlords, said Salama of the New York association, even as it’s unclear when office workers will return. His company, Capital Properties, is swapping out 900 air conditioning filters at its two Manhattan office buildings for double the price it would normally pay.

Many of the methods to reduce pathogens have been around for years, such as UV light and bipolar ionization, which releases electrically charged atoms that attach to and neutralize viruses and bacteria. Those technologies were geared more to hospitals than commercial buildings, which put more of an emphasis on saving energy than killing germs. That’s changing now.

Allan Reagan, chief executive officer of Flix Brewhouse, adopted elaborate protocols for sanitizing and creating social distancing at his 10 dine-in movie houses. As the risk of airborne spread drew more attention, he hired Trane Technologies to install bipolar ionization for all 87 of the company’s screening auditoriums, at $1,500 a piece.

A study showing the system kills as much as 99% of pathogens won Reagan over, and Flix Brewhouse opened in San Antonio to the public for two weeks to try the system. He said the venue had about 700 visitors, including 50 employees, and he hasn’t heard of any Covid cases that arose. All of Flix’s theaters are closed for now, mainly because of a lack of new films from Hollywood, he said.

“We tried it out, declared victory, and we’ll come back when we have some good content,” Reagan said. “In the meantime, we’ll be retrofitting our other theaters. So when they reopen we’ll have this technology across the circuit.”

Fredric Lubit, a dentist with two offices in New Jersey, purchased four Carrier OptiClean air scrubbers at $4,500 each. The machine, which looks similar to a tall filing cabinet, sucks air though a high-efficiency particulate air, or HEPA, filter. He also purchased a $10,000 machine for each office that saturates a room with UV light for two minutes to destroy microbes.

Carrier began designing the OptiClean in March by hot-rodding the inside portion of a residential HVAC system with a bigger fan and motor, along with other parts. The product was initially aimed at hospitals, but demand is now coming from schools and small offices, said Chris Nelson, president of Carrier’s HVAC unit, who declined to provide sales numbers.

It’s unclear whether the virus could squeeze through. While studies have shown HEPA filters can block particles as small as 0.1 micron, tiny enough for the coronavirus particles that can float on air, the rating on the heavy-duty filters is only for particles the size of 0.3 microns, according to a July 9 paper by consulting firm McKinsey & Co.

For Lubit, the outlay is still worthwhile.

“You can’t put a price on your health, your staff’s health and, in my case, patients’ health,” he said.