Measurement of the leak rate of masks used for anticancer drug handling using a mask fitting tester

Abstract

Background Exposure to inhalation of anticancer drugs is frequent in anticancer drug handling. Using an activated carbon mask with the ability to remove particulates and vapors of anticancer drugs may be effective. Mask fitting performance is important, because low fitting performance leads to inhalation via bypassing the mask filter (leak). This study evaluated the leak rate of multiple-shaped masks. Methods Activated carbon and nonactivated carbon masks of the pleated-type (like surgical mask) and cup-type were used. Four pharmacists wore the masks and a fitting tester was employed. The particle reduction rate of particles in ambient air was calculated using: particle count (outside - inside)/outside × 100 (%). Leak rate was calculated as the difference in the particle reduction rate due to the presence or the absence of a seal in the mask surroundings. Results Reduction rates of the pleated-type nonactivated carbon mask and the pleated-type activated carbon mask were 14.8% and 34.8% (mean). These values significantly increased to 85.6% and 83.3% upon sealing the mask surroundings. Particle reduction rates of the cup-type nonactivated carbon mask and activated carbon mask were 99.3% and 33.6%. When mask surroundings were sealed, these values were 99.6% and 39.2%. Leak rates of pleated-type nonactivated carbon mask, pleated-type activated carbon mask, cup-type nonactivated carbon mask, and cup-type activated carbon mask were 70.8%, 48.5%, 0.3%, and 5.6%, respectively. Conclusion A difference was found in the leak rate between masks used in anticancer drug handling. Based on the low leak rate, the cup-type activated carbon mask was thought to be effective.