Testing a n95 ordered off of ebay

With all of the shortages, I know several people turning to ebay to buy their own - obviously most of the ones out there are Chinese made kn95 (their version of n95) - is there any self test that anyone knows to see if these masks actually work? I ordered some for my team - as our option is this or a surgical mask - but want to test to see if the KN95's are better or not
Source: Student Doctor Network - Category: Universities & Medical Training Authors: Tags: Pharmacy Source Type: forums