You think they are going to $$$ to protect us in the office? I rarely see them change a regular filter!
HVAC (heating/ventilation/air conditioning) systems are not thought to be a significant factor in the spread of coronavirus.
Many modern air conditioning systems will either filter out or dilute the virus. Ventilation systems with highly effective filters are a key way to eliminate droplets from the air, said Harvard environmental health researcher Joseph Gardner Allen.
Filters are rated by a MERV system – their “minimum efficiency reporting value” that specifies their ability to trap tiny particles. The MERV ratings go from 1 to 20. The higher the number, the better the filtration.
HEPA filters have the highest MERV ratings, between 17 and 20. HEPA filters are used by hospitals to create sterile rooms for surgeries and to control infectious diseases. They’re able to remove 99.97% of dust, pollen, mold, bacteria and other airborne particles as small as 0.3 microns.
For context, this coronavirus is thought to be between 0.06 to 1.4 microns in size.
But “HEPA filtration is not always going to be feasible or practical,” Allen said. “But there are other filters that can do the job. What is recommended now by the standard setting body for HVAC is a MERV 13 filter.”
High-efficiency filters in the 13-to-16 MERV range are often used in hospitals, nursing homes, research labs and other places where filtration is important.
“If you’re an owner of a home, building or mall, you want to have someone to assess your system and install the largest MERV number filter the system can reliably handle without dropping the volume of air that runs through it,” advised Erin Bromage, an associate professor of biology at the University of Massachusetts Dartmouth.
“In addition, virtually all modern air conditioning systems in commercial buildings have a process called makeup air where they bring in air from outside and condition it and bring it inside,” Bromage said. “It’s worse in regards to energy, but the more outside air we bring in, the more dilution of the virus we have and then the safer you are