Efficacy of powered air-purifying respirators (PAPRs) for source control of simulated respiratory aerosols.

Background: Loose-fitting powered air-purifying respirators (PAPRs) are a popular alternative to the use of filtering facepiece respirators for health care workers. Although PAPRs protect the wearer from aerosol particles, their ability to block infectious aerosol particles exhaled by the wearer from being released into the environment (called source control) is unclear.

Methods: The source control performance of 4 PAPRs with loose-fitting facepieces were tested using a manikin that exhales aerosol particles. The PAPRs were tested by themselves and in combination with a face-worn product intended to provide source control (either a surgical mask or an N95 filtering facepiece respirator).

Results: Two PAPR facepieces with filtration panels significantly reduced the release of exhaled aerosols into the environment, while 3 facepieces without such panels did not. Wearing a surgical mask or respirator under the facepiece significantly improved the source control performance.

Conclusions: Most PAPR facepieces do not block aerosols exhaled by the wearer. Facepieces designed to filter exhaled particles can prevent aerosols from being released into the environment. Wearing a surgical mask or a filtering facepiece respirator under the facepiece can also provide source control, but PAPRs are not typically certified for use with masks and respirators.