Can we fillter inlet air of AHU directly from HEPA?
Air filteted directely through HEPA will chock/demage the HEPA so its is first filterd through pre fiters and bag filters.
no HEPA filter is the end filtration of an AHU and Area.
Before that, it is better to install Outside air unit that contains primary filters. and cleaned very often, for intake or air…for better longitivity of v & pre filter of AHU…
yes its necessary
called mesh filter or aluminium washable filters