Chimney Safety Institute of America (CSIA) Certification Practice Test

How does a positive pressure respirator function?

1. It uses filters to clean the air

2. A fan pushes air into the mask

3. It relies on tight-fitting seals

4. It absorbs air with activated charcoal

The correct answer is: A fan pushes air into the mask

A positive pressure respirator functions by utilizing a fan to push air into the mask. This design ensures that the air supplied to the wearer is at a higher pressure than the surrounding environment, which serves to prevent any contaminants from entering the mask. The airflow created by the fan not only provides the wearer with breathable air but also creates a protective barrier against external pollutants and hazardous airborne substances. While some respirators may use filters to clean the air, focus on the features that define positive pressure respirators emphasizes the role of the fan in delivering a consistent airflow. Additionally, while sealing is important for effective respirator operation, the pressure differential created by the airflow is what primarily characterizes the positive pressure system. This means that a tightly fitting seal alone is not sufficient for the functionality of this type of respirator. The mention of activated charcoal is relevant to certain filtration systems, but is not indicative of how positive pressure respirators operate as a primary breathing aid.