What is an Air-Purifying Respirator (APR)?

An Air-Purifying Respirator (APR) is correctly identified as a device that removes contaminants by passing ambient air through a filter. This type of respirator functions by filtering out harmful particles, gases, and vapors from the air that the wearer inhales, making it suitable for environments where airborne contaminants are present but oxygen levels are still adequate.

The operation of an APR hinges on its filter system, which can vary depending on the type of contaminants it is designed to address. This can include particulate filters that capture solid particles, or chemical filters that adsorb gases and vapors. The effectiveness of the respirator is highly dependent on the quality of the filters used.

In contrast, other options such as a device that only provides oxygen, which implies a supply of breathable gas without filtration, do not align with the function of APRs. Full-face protective gear may imply comprehensive coverage, but it's not a defining characteristic of all APRs, as they can come in various forms including half-masks. Additionally, the notion of a respirator that cannot be reused does not apply, as many APRs are designed for multiple uses depending on the manufacturer’s guidelines and the conditions they are used under. Thus, option B stands out as the accurate description of