ISRP 2002 abstract
National Personal Protection Laboratory, NIOSH, Pittsburgh, Pennsylvania, USA
|Correlation between Quantitative Fit Factors and Protection Factors Measured under Actual Workplace Environments at a Steel Foundry||
Past studies have found little to no
correlation between workplace protection factors and quantitative fit
factors (FFs). The purpose of this new study was to investigate the
correlation between FFs and protection factors (PF) for half-facepiece,
air-purifying respirators under actual workplace environments at a steel
foundry. Fifteen burners, welders, and chippers wore two respirator
models. Each worker donned a respirator twice per day for two days.
Quantitative FFs were first obtained for each donning using the
PortaCount Plus in a separate room. Without redonning the respirators,
workers performed normal work for one to two hours, and protection
factors were measured by collecting ambient and in-facepiece samples
simultaneously. A second fit-test was conducted without redonning the
respirator. Fit factors were obtained by averaging the results from the
first and second fit-tests.
The resulting FFs had a geometric mean (GM) of 400 (range=10-6010) and a geometric standard deviation (GSD) of 6.1. The protection factors had a GM of 920 (range=13-230000) and a GSD of 17.8. The protection factors were found to be significantly correlated with the FFs (R2=0.55 and p-value=0.0001). This field study has, therefore, shown fit factor to be a meaningful indicator of respirator performance under actual workplace environments.