[2] Tight-fitting PAPRs require a fit test in hazardous workplace environments, while loose-fitting PAPR users can avoid OSHA fit test requirements in certain hazardous workplace environments (see OSHA's respirator assigned protection factors for more information).

Loose-fitting PAPRs can be useful when a fit test for a tight-fitting respirator cannot be successfully passed, for example when facial hair is present.

[2][3] When comparing various makes and models of PAPR, the supporting documentation from each of the respective manufacturers should be consulted in order to confirm the APF value of each product.

In healthcare settings involving a live virus, CDC recommends that a practical replacement cycle be implemented.

[CF2] According to the NIOSH Respirator Selection Logic, PAPRs are recommended for concentrations of hazardous particulates or gases that are greater than the relevant occupational exposure limit but less than the immediately dangerous to life or health (IDLH) level and the manufacturer's maximum-use concentration, subject to the respirator having a sufficient assigned protection factor.

[2] Because they provide higher assigned protection factors, PAPRs are suitable for use during aerosol-generating procedures[1] and by hospital first receivers.

They were used by the U.S. Army Aeromedical Isolation Team to perform medical evacuations of patients with highly infectious diseases.

In the United States, they must be certified to resist permeation of chemical warfare agents, which may involve additional protective coverings; that gas or vapor will not pass through the filter before a specified amount of time; and its ability to fit a wide range of facial sizes and shapes.