Assigned Protection Factor (APF) Law and Legal Definition

According to 10 CFR 20.1003 [Title 10 – Energy; Chapter I -- Nuclear Regulatory Commission; Part 20 -- Standards for Protection Against Radiation; Subpart A -- General Provisions], the term assigned protection factor (APF) means “the expected workplace level of respiratory protection that would be provided by a properly functioning respirator or a class of respirators to properly fitted and trained users. Operationally, the inhaled concentration can be estimated by dividing the ambient airborne concentration by the APF.”