Get the Most Out of Masking - California Department of Public Health (1/14/2022)
Types of Masks and Respirators - Center for Disease Control and Prevention (CDC)
NIOSH-approved N95 Particulate Filtering Facepiece Respirators
NIOSH Certified Equipment List
Counterfeit Respirators / Misrepresentation of NIOSH-Approval - CDC - The National Personal Protective Technology Laboratory (NPPTL)
NIOSH Science Blog - CDC
The National Institute for Occupational Safety and Health (NIOSH)