At least semiannual testing required for each PEC (Primary Engineering Control. i.e. Hood, Isolator, BSC, Cleanbench, Glovebox, CAI, CACI, etc.). In higher usage facilities, more frequent testing may be prudent. Kit contains 10 gel coated contact plates of Tryptic Soy Agar (TSA) w/Lecithin and Polysorbate 80 additives, $35.49/sleeve of 10.