Anytime someone dons a tight fitting respirator, the user should conduct two types of seal checks. It is necessary to ensure that the respirator is working properly. Before donning the respirator make sure that all valves and straps are present, it is clean, and there is no signs of distortion.
Positive Pressure Test
- If removable, remove the exhalation valve cover.
- Cover the exhalation valve with the palm of the hand while gently exhaling to inflate the facepiece.
- The respirator should remain inflated and this indicates that there is no leakage and the seal is tight.
- If the respirator deflates, reposition and retest.
Negative Pressure Test
- Cover the inhalation valve openings on the canisters or cartridges with the palm(s) of the hand while inhaling gently to create slightly collapse the respirator. (negative pressure)
- Hold for 10 seconds while keeping the canisters or cartridges covered.
- If the respirator remains under negative pressure and there no sign of leakage, this indicates that seal is tight.
- If there is leakage, reposition and retest.