What does an Air Purifying Respirator do?

An Air Purifying Respirator (APR) is designed to protect the wearer from inhaling harmful contaminants in the air by removing those contaminants through a process of filtration or chemical reaction. The respirator uses various filters or cartridges that can effectively capture particular types of pollutants, ensuring that the air the user breathes is cleaner and safer.

The effectiveness of an APR is contingent on the type of filter it employs, which can be tailored to address specific contaminants such as particulate matter, gases, or vapors. This capability is crucial in environments where harmful airborne substances are present, allowing for safe and breathable air to be provided to the wearer.

In contrast, other options do not correctly define the function of an APR. For instance, providing oxygen in high altitudes does not apply, as APRs do not supply oxygen but rather clean existing air. Similarly, supplying continuous airflow does not accurately describe the function of APRs, which work primarily by filtering rather than providing a constant stream of air. Lastly, while APRs do filter out particles, they are not limited to just large particles; they can also filter out smaller particulate pollutants, gases, and vapors, which makes the generalization in one of the options incorrect.