A comparison of controlled negative pressure and aerosol quantitative respirator fit test systems by using fixed leaks.
An automated version of a new method for quantitative respirator fit testing by controlled negative pressure was compared with a computerized aerosol fit test system. The controlled negative pressure technique eliminates many of the problems associated with aerosol and pressure decay fit test methods. A series of fixed leaks was used to compare the leak measurement capabilities of the controlled negative pressure system against a standard computerized aerosol fit test system. Negative pressure and aerosol fit factors determined for a series of fixed leaks through hypodermic needles were highly correlated with each other (r = 0.998) and with the cross-sectional areas of the leak needles (r greater than 0.995).
Crutchfield
C D
CD
School of Health Related Professions, University of Arizona, Tucson 85719.
Murphy
R W
RW
Van Ert
M D
MD
D004867:Equipment Design; D005240:Feasibility Studies; D012134:Respiratory Protective Devices; D015919:Ventilators, Negative-Pressure