Respirator seal check

Also referred to a user seal check or fit check. Don the respirator, mold nose piece to engage a snug fit. Place hands over respirator, careful not to disturb position. Positive seal check: Exhale sharply (puff). No leakage should occur around the respirators periphery. Negative seal check: Inhale sharply. If no leakage, the negative pressure will make the respirator appear to cave inward.