2 x Odor Control Activated Carbon Charcoal Cut-to-fit Replacement filter Pad Sheet for Air Purifiers

I just received mine today for my air purifier. But after awhile how do I wash it? Or do i replace it?

Does anyone know if this product will reduce refrigerator odors, or is it only to be used in appliances with air flow?

Dim. of the filter: approx. 17.5"x 11.8" and 0.4" thick (inches) Product Dim. 12 x 8.8 x 2.2 inches, can someone please explain? Thanks.

Will this product restrict air flow from a floor vent?