Efficiency of Protective Mask Filters in Removal of Hexavalent Chromium Mist

Abstract

BACKGROUND AND OBJECTIVE: Personal protective equipments (PPE) are common equipments for control of workers exposure to harmful agents in work environment. Regarding to the critical role of the filter collection efficiency under hazardous conditions such as exposure to carcinogen materials, this study was performed to determine the effect of different factors on efficiency of respirator filters in removing hexavalent chromium mist. METHODS: In this quasi-experimental study, homogenous chromium mist at different conditions (concentration 1.25 and 2.5 mg/m3, relative humidity 50 and 80% , and temperature 0-5 and 35-40 oC) passed through two types of respirator filters (MSA and Spasciani). All samples (n= 384) were collected, using NIOSH 7600 test method at upstream and downstream of respiratory filters, simultaneously and analyzed, using an atomic absorption spectrometer and inductively coupled plasma (ICP), respectively. FINDINGS: Although type of filter had significant effect on hexavalent chromium mist removal, the ANOVA test results indicated that the increase of chromium mist concentration and relative humidity resulted a significant decrease in removal efficacy 0.53% and 0.42%, respectively (p<0.001). The temperature had not significant effect on filter efficiency.CONCLUSION: Increase of hexavalent chromium mist concentrations and relative humidity has significant negative effect on collection efficiency of respirator filters.

Keywords

• hexavalent chromium
• mist
• respirator
• efficiency
• filter
• temperature
• relative humidity
• concentration
• penetration