<<< Back to Air-purifying vs. Atmosphere-supplying Respirators

Three Kinds of Air-purifying Respirators       Particulate Respirators   Combination Respirators   Gas & Vapor Respirators   capture particles in the air, such as dusts, mists, and fumes do not protect against gases or vapors generally become more effective as particles accumulate on the filter and plug spaces between the fibers filters should be replaced when user finds it difficult to breath through them (see Selection Criteria for Particulate Filters) are normally used in atmospheres that contain hazards of both particulates and gases   have both particulate filters and gas/vapor filters may be heavier are normally used when there are only hazardous gases and vapors in the air   use chemical filters (called cartridges or canisters) to remove dangerous gases or vapors do not protect against airborne particles are made to protect against specific gases or vapors provide protection only as long as the filter's absorbing capacity is not depleted the service life of the filter depends upon many factors and can be estimated in various ways (see Respirator Change Schedules)