Which type of breathing apparatus recycles the user's exhaled air?

Closed circuit breathing apparatus is designed to recycle the user’s exhaled air, making it a highly efficient option for situations where air supply is limited. This type of apparatus captures and cleans the exhaled air by removing carbon dioxide and replenishing oxygen, allowing the firefighter to reuse the air instead of releasing it into the environment.

This method is particularly advantageous in enclosed or confined spaces, where fresh air is scarce, as it reduces the amount of external air needed and extends the duration of breathable air available to the user. In contrast, other types of breathing apparatus—like air-purifying respirators, supplied air, and powered air—do not recycle exhaled air but either filter or provide a continuous flow of fresh air instead. Thus, the closed circuit system is distinguished by its unique ability to recycle, making it crucial for efficient breathing in hazardous situations.