


The time you have remaining on a filter is unaffected by your actions (running or jumping), but it is theorized that if Artyom is at "rest" (not breathing heavily, or even better standing near a fire to "calm" him) you will get more time on the filter when you swap one in. It varies, a random filter found in the game world will usually have about one minute of air time, whereas a filter bought from a merchant will have 10 minutes of air time.
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Since google searches for how the filters actually work in the game have come up with many varied responses, some of them contradictory, I thought I'd share the known facts here.
