Personal Protective Equipment Guide
There’s a range of PPE products which meet different standards and approvals. Proper understanding & selection is critical.
PPE Performance Levels
HIGH PERFORMANCE: N95
NIOSH Approved N95 Particulate Respirator
High Fluid Resistance: 160 mmHg
Filtration Efficiency: PFE = 99.9% @ 0.1 micron
Breathability - Delta P: > 5.0 mm H2O/cm2
Flame Spread: Class 1 (Flame Resistant)
ASTM LEVEL 3
Surgical Mask with high fluid resistance
High Fluid Resistance: 160 mmHg
Filtration Efficiency: BFE/PFE ≥ 98% @ 0.1 micron
Breathability - Delta P: > 5.0 mm H2O/cm2
Flame Spread: Class 1 (Flame Resistant)
ASTM LEVEL 2
Surgical Mask with moderate fluid resistance
High Fluid Resistance: 120 mmHg
Filtration Efficiency: BFE/PFE ≥ 98% @ 0.1 micron
Breathability - Delta P: > 5.0 mm H2O/cm2
Flame Spread: Class 1 (Flame Resistant)
ASTM LEVEL 1
Surgical Mask with some fluid resistance and less filtration
High Fluid Resistance: 80 mmHg
Filtration Efficiency: BFE/PFE ≥ 95% @ 0.1 micron
Breathability - Delta P: > 5.0 mm H2O/cm2
Flame Spread: Class 1 (Flame Resistant)
UNTESTED & MINIMUM PERFORMANCE
Masks which have not been tested to NIOSH, ASTM or comparable standards
High Fluid Resistance: n/a
Filtration Efficiency: n/a
Breathability - Delta P: n/a
Flame Spread: n/a
USA PPE Certification & Standards
FDA
The Federal Drug Administration regulates surgical masks and N95 respirators differently based on their intended use.
NIOSH
The U.S. National Institute for Occupational Safety and Health (NIOSH) classifies PPE with air filtration ratings which describing the ability to protect in occupational settings.
ASTM
Founded in 1898 as the American Section of the International Association for Testing Materials, ASTM International is a private organization that creates testing standards to measure PPE performance.
CDC
The Centers for Disease Control and Prevention (CDC) is the parent organization for NIOSH & the leading national public health institute of the United States.
The FDA's Role in Regulating Personal Protective Equipment (PPE)
Face masks and respirators are regulated by FDA when they meet the definition of a device under section 201(h) of the Federal Food, Drug, and Cosmetic Act (FD&C Act).
Generally, face masks fall within this definition when they are intended for a medical purpose,
Masks and other PPE used for medical purpose are reviewed by the FDA known as Premarket Notification or 510(k) clearance, where manufacturers have to show they meet specific criteria for performance, labeling, and intended use to demonstrate substantial equivalence.
Demonstration is conducted by conforming to standards (such as ASTM standards) for barrier performance and resistance to tears and snags. Voluntary consensus standards may also be used to demonstrate sterility (when applicable), biocompatibility, fluid resistance, and flammability. Manufacturers must validate the methods used to test conformance to standards.
NIOSH Air Filtration Ratings
NIOSH Particulate Respirator Class Minimum Efficiency Levels
The National Institute for Occupational Safety and Health is the United States federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. NIOSH is part of the Centers for Disease Control and Prevention (CDC) within the U.S. Department of Health and Human Services.
The NIOSH air filtration rating is the U.S. National Institute for Occupational Safety and Health (NIOSH)'s classification of filtering respirators. The ratings describe the ability of the device to protect the wearer from dust and liquid droplets in the air.
NIOSH has currently established nine classifications of approved particulate filtering respirators based on a combination of the respirator series and efficiency level. The first part of the filter's classification indicates the series using the letters N, R, or P to indicate the filter's resistance to filtration efficiency degradation when exposed to oil-based aerosols (e.g., lubricants, cutting fluids, glycerine, etc.)
N for not resistant to oil. Used when oil particulates are not present.
R for resistant to oil. Used when oil particulates are present and the filter is disposed of after one shift.
P for oil-proof. Used when oil particulates are present and the filter is re-used for more than one shift.
ASTM Testing Standards
It’s important to note that ASTM International has no role in requiring or enforcing compliance with its standards. The standards, however, may become mandatory when referenced by an external contract, corporation, or government such as they are by the FDA.
With regard to filtration test methods, the NIOSH certification standards are a more conservative set of filtration test parameters as compared to the ASTM standards such as the ASTM F2299 standard included in the FDA's regulatory requirements.
The NIOSH test uses a charge-neutralized aerosol, creating a worst-case scenario for a filtration medium, while the ASTM method uses an unconditioned aerosol, which means that the aerosol's particles are charged to some extent. The NIOSH test uses an entire respirator that has been preconditioned for 24 hours at 38°C and 85 percent relative humidity, which represents a challenging high-humidity environment.
The ASTM method tests a sample of the filtration material with no preconditioning. In addition, the NIOSH method is run until a mass of approximately 200 milligrams is deposited on the filter—a relatively large amount of mass—while there is no specific requirement for a specific mass to be tested in the ASTM method.