From EHS Today:
In its newly published guidance document, Assigned Protection Factors (APF), OSHA provides employers with vital information for selecting respirators for workers exposed to contaminants in the air.
The guidance focuses on mandatory respirator selection provisions added to the existing Respiratory Protection standard. OSHA revised this standard in 2006 to add APFs and Maximum Use Concentration (MUC) provisions.
APF means the workplace level of respiratory protection that a respirator or class of respirators is able to provide to workers. The higher the APF number (5 to 10,000), the greater the level of protection provided to the user. APFs are used to select the appropriate class of respirators that will provide the necessary level of protection against airborne contaminants. Such exposures can come from particles or a gas or vapor.
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