Abstract
The purpose of this study was to assess the effect of personal variables on the fit of the respirators used by firefighters and workers in highly polluted environments. However, resistance from many plants managers was met to conduct the study on their workers. Therefore, we were forced to limit the study on firefighters who were found very cooperative. Forty volunteer firefighters from different departments participated in the study. They were subjected to a daily leak rate measurement using a Control Negative Pressure (CNP) fit tester for five consecutive days. Two types of respirators were used for each volunteer: the Drager type and the MSA. At the end of the study, the association between face shape and presence of beard with the respirator leak rates was investigated. A significant difference in the leak rate was detected between the two types of respirators used, with the Drager respirator having higher leak rates. The presence of a beard increased dramatically the leak rate whatever the face shape was. The oval shape was the best fitting to the respirators, followed by the rounded and finally the rectangular face. The study recommends that personal variables like face shape must be taken into consideration and fit testing must be carried out periodically, to specify the respirator that best fits each firefighter. Having beard must be absolutely prohibited, since it can be life threatening in environmental dangerous conditions such those encountered during extinguishing fires and overhaul situations.