Common Types of Masks

*Specifically referring to medical grade masks vs OTC Comfort and dust masks

 

Filter Performance

Reduction in concentrations of specific aerosols (typically 0.1 – 0.5 microns in size) in air that passes through the filter.  For reference, red blood cells are about 7 microns wide.

 

Aerosol

Suspension of fine solid or liquid droplets in air or another gas.

 

Test Agent

Aerosol that is generated in the filter performance test.

 

Total Inward Leakage

Amount of specific aerosol that enters tested respirator via both filter penetration and seal leakage while wearer performs exercise in test chamber.

 

Inward Leakage

Amount of specific aerosol that enters tested respirator while wearer performs normal breathing for 3 minutes.

 

Pressure Drop

The resistance air is subjected to as it moves through the medium.

 

Personal Protective Equipment (PPE)

Any gear necessary to minimize exposure to hazards; includes masks, gloves, goggles, clothing, etc.