What indicates that a respirator is functioning properly?

The function of a respirator is critical for ensuring that users are protected from harmful airborne contaminants. The correct choice highlights a key aspect of respirator operation: the air you exhale passes through the cartridges. This indicates that the respirator is effectively filtering out pollutants, as exhaled air should ideally be passing through the filtering components rather than escaping unfiltered.

The design of respiratory protection is such that inhaled air is cleaned by the cartridges, and if exhaled air is also directed through these cartridges, it confirms that the sealing mechanisms are functioning as intended. This is a crucial operational verification step that allows wearers to ascertain that their respirator is effectively filtering the air both ways, ensuring that harmful substances are not re-entering their breathing zone.

The other options, while relevant to the overall function and fit of the respirator, do not directly indicate its operational capability in the same way. Although having clean inhaled air and a snug fit are important for comfort and efficiency, the fundamental verification of the respirator’s filtering system is demonstrated through the air that passes through the cartridges upon exhalation.