Inward leakage in tight-fitting PAPRs.

Frank C Koh, Arthur T Johnson, Timothy E Rehak

Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.

Journal of environmental and public health 2011

filter terms:

A combination of local flow measurement techniques and fog flow visualization was used to determine the inward leakage for two tight-fitting powered air-purifying respirators (PAPRs), the 3M Breathe-Easy PAPR and the SE 400 breathing demand PAPR. The PAPRs were mounted on a breathing machine head form, and flows were measured from the blower and into the breathing machine. Both respirators leaked a little at the beginning of inhalation, probably through their exhalation valves. In both cases, the leakage was not enough for fog to appear at the mouth of the head form.