Tests boilers, tanks, fittings, pipes, and similar objects to detect and locate leaks, using compressed air or water pressure: Installs fittings on object to seal outlets and connects object to high-pressure air or water line, using hand tools. Job Purpose: As a WEM Tester, you will safely pressure and/or leak test grey iron, ductile iron, steel and stainless-steel castings, while following all Work Instructions.