Question of the Day – Thursday January 4, 2018

Question:  With regard to respirators used in the occupational setting, what is the so-called Assigned Protection Factor (APF)?

Answer: The Occupational Safety and Health Administration (OSHA) states “Assigned Protection Factor (APF) means the work-place level of respiratory protection that a respirator or class of respirators is expected to provide to employees when the employer implements a continuing, effective respiratory protection program as specified by [OSHA]” (; accessed December 2017)