Originally Posted by
hoss183
Who says these filters actually filter airbourne viral contamination 100% or even at all?
The manufacturers do. It's HEPA filters same as used in hospital sterile surgery rooms. Filters best compared to anything else.
Together with the fact that the air sourced from the engines is about 260°C before conditioning and the aircraft flies at altitude, for airborne contamination - speaking of air quality - aboard a modern jet in flight is as safe as it gets.