Questions about filter direction for a hand-held vac

[ChuckM]

Anyone know for the filter cartridge in the image, whether the dirty air gets filtered in the manner shown in #1 (red) or 2) in blue?

The video (0:20) shows the filter removal -


Seems to me 2) is the way air is filtered.

If so, can the filter be used in the opposite manner such that dirty air goes in as shown in #1)?

 

[squall_line]

Considering the "pre-filter" wraps on the outside, I'd say you're correct that #2 is the flow direction.

As for reversing the flow, usually on a pleated filter, there are reinforcements on the leeward side of the filter to prevent it from collapsing under pressure while in use.  If you were to reverse the flow on that filter, it may or may not want to separate from itself and turn into a balloon instead of a pleat.

 

[ChuckM]

Thanks for your response. I've used the filters as designed, as explained in a separate post about upgrading the shop vacs with those filters.