BART improving air filters to limit coronavirus particles
BART is equipping its cars with denser air filters that capture more dangerous coronavirus particles, in the transit system’s latest move to outfit itself in the continuing pandemic.
Agency officials announced Tuesday that they plan to install filters rated with a minimum efficiency reporting value of MERV14 — up from the old filters’ rating of MERV-8 — following a pilot program over the past six months. The filters have denser folds and can capture particles as small as 0.3 to 1 micron. The old filters capture particles as small as 3 microns.
Health officials have zeroed in on ventilation and air filtration systems as an important part of efforts to prevent coronavirus from spreading in confined spaces such as office buildings, along with other precautions like wearing a face covering.
The American Society of Heating, Refrigerating and Air-Conditioning Engineers recommends efficiency ratings of at least MERV-13 to limit the spread of coronavirus aerosols, which are smaller and lighter than respiratory droplets.
BART trains will have their air filters swapped out as they go in for preventive maintenance. The agency did not detail how long it would take to outfit all of its train cars with the new filters, or how much the project would cost.
In the months since the vast majority of riders cleared off of BART last spring, the system — like many other transit agencies across the country — has sought to reassure the public that its trains are safe to rider during the pandemic.
BART cars already replace the air in a train roughly every 70 seconds, according to the transit agency, which is also exploring adding ultraviolet lighting rods to its HVAC systems to further improve filtration.
Weekday ridership on BART these days is typically less than 15% of prepandemic levels.