U.S. Environmental Protection Agency levels of protection can be used as a starting point for assembly of protective clothing ensembles. However, each ensemble must be tailored to the specific situation to provide the most appropriate level of protection.
When response activities are conducted where atmospheric contamination is known or suspected to exist, personal protective equipment must be worn.
Personal protective equipment is designed to prevent/reduce skin and eye contact as well as inhalation or ingestion of the chemical substance.
Protective equipment to protect the body against contact with known or anticipated chemical hazards has been divided into four categories.
Level A protection should be worn when the highest level of respiratory, skin, eye and mucous membrane protection is needed.
Level B protection should be selected when the highest level of respiratory protection is needed, but a lesser level of skin and eye protection. Level B protection is the minimum level recommended on initial site entries until the hazards have been further identified and defined by monitoring, sampling, and other reliable methods of analysis, and equipment corresponding with those findings utilized.
Level C protection should be selected when the type of airborne substance is known, concentration measured, criteria for using air-purifying respirators met, and skin and eye exposure is unlikely. Periodic monitoring of the air must be performed.
Level D is primarily a work uniform and is used for nuisance contamination only. It requires only coveralls and safety shoes/boots. Other PPE is based upon the situation (types of gloves, etc.). It should not be worn on any site where respiratory or skin hazards exist. Refer to The Office of Emergency and Remedial Response. Environmental Response, Division. See "Interim Standard Operating Safety Procedures" for full details.
The type of environment and the overall level of protection should be reevaluated periodically as the amount of information about the site increases and as workers are required to perform different tasks.