How do you test for positive pressure on a face piece of SCBA?

Testing for positive pressure on a face piece of a Self-Contained Breathing Apparatus (SCBA) is critical for ensuring the safety and effectiveness of the equipment during firefighting operations. The correct method involves breaking the seal while feeling for air movement, which is key to determining the pressure within the mask.

When breaking the seal of the face piece, you should not feel any rush of air entering the mask. If the SCBA is functioning properly and maintaining positive pressure, there should be no air movement into the face piece from the outside environment. This indicates that the SCBA is effectively protecting the user from inhaling hazardous materials. The design of a positive pressure SCBA allows for a small positive pressure inside the mask, which ensures that any ambient air or contaminants cannot infiltrate the protective seal.

This method allows for a quick and effective check of the equipment before entering hazardous environments, ensuring firefighter safety. The other methods mentioned wouldn't effectively determine the positive pressure status of the SCBA face piece in the same way that breaking the seal does.