DPT 8.0
Levels of PPE
•Level A - IDLH environments, fully encapsulated, requires SCBA
•Level B - Chemicals or substances with inhalation hazard, requires SCBA or SAR
•Level C - Known contaminants, requires air-purifying respirator
LEVELS OF PPE

Level A PPE is required for exposures in the area of a release (the hot zone), if air concentrations exceed those that are immediately dangerous to life and health (IDLH).  This level of protection mandates a self-contained breathing apparatus (SCBA), is fully encapsulating, and is resistant to liquid and vapor penetration.  This level of PPE is difficult to wear for long periods of time, and the wearer is exposed to a claustrophobic environment with risk of heat stress.

Level B PPE is required for chemicals or substances that pose a potential inhalation hazard but requiring a lesser level of skin protection.  Although this PPE ensemble offers less splash protection than Level A, when coupled with an SCBA or supplied air respirator (SAR), it provides adequate vapor protection. This is the minimum level of protection for personnel dealing with vapor-prone hazardous materials.

Level C PPE should be used when the atmospheric contaminants have been identified, (such as nerve or blister agents), concentrations measured and determined to below a hazardous level, and an air purifying respirator (along with an agent-specific filtering canister) is appropriate and available to remove the contaminants involved.  This ensemble is protective for both liquid and vapor.  An air purifying respirator is one in which ambient air passes through a filter element or canister that removes gaseous or particulate contaminants.  There are two basic types of air-purifying respirators. A negative-pressure respirator functions when the ambient air is pulled across the filter by the user’s inspiration. A positive-pressure, powered air purifying respirator (PAPR) has a battery-operated blower that propels ambient air through a filter and then into a mask.