HAZWOPER Respirator Protection Factors
So, how do we measure the chemical concentration of a respirator for HAZWOPER work?
After the oxygen content has been determined for a HAZWOPER site, and after the chemical has been identified and the warning properties have been assessed, the chemical concentration needs to be determined to decide if an air-purifying respirator can be used. An air-purifying respirator cannot be used in an immediately dangerous to life or health (IDLH) atmosphere. (If you were on a different planet that did not have an oxygen rich atmosphere, you could not use an air-purifying respirator)! An IDLH atmosphere is defined as a condition(s) that will cause severe injury or death without warning. The IDLH of every chemical that you could be exposed to must be determined prior to entry into a work area. The next step in determining the use of an air-purifying respirator is to determine the life limit or service limit of the canister. When this limit has been reached, the canister can no longer provide sufficient protection. The service life of the canister is normally written on the canister. If it is not provided on the canister, call the manufacturer to obtain the service life.
Items that shorten the life span of a canister:
• Storage of the canisters in a very dry or very humid environment
• Breathing rates of humans vary from one person to another - a person who breathes faster than another will find their canister to clog faster
• The higher the concentration of the contaminant, the sooner the canister will become clogged
• A canister that has exceeded its shelf life should not be used
• Never use a canister that has not been wrapped in a protective package
The level of protection that can be provided by a respirator is indicated by the respirator's protection factor. The Protection Factor (PF) is determined experimentally by measuring face piece seal and exhalation valve leakage. The number indicates the relative difference in concentrations of substances outside and inside the face piece.
Determining the Protection Factor of a Respirator for HAZWOPER Work:
The protection factor (PF) is the level of protection that a respirator provides. In essence, it tells a worker if the respirator selected is adequate for protection from the chemical concentration in the work zone. For example, a respirator with a PF of 10 can be used when the concentration of the contaminant is up to but not more than 10 times the chemical OSHA PEL. If the chemical concentration is more than the PF multiplied by the OSHA PEL, then a respirator with a higher protection factor must be selected. Multiply the PF for the respirator in question by the chemical's OSHA PEL or threshold limit value (TLV). Here is the equation: (PF) (PEL or TLV) = Maximum Value Limit. The value calculated is known as the maximum value limit (MVL). This value is the highest concentration of a chemical(s) for which the respirator is acceptable. If the chemical concentration is above the MVL calculated, a higher respiratory protection is required i.e., a better respirator is required.
(PF) (PEL or TLV) = Maximum Value Limit