ABSTRACT
Chemical cartridges or canisters are used for protection against exposure to gaseous air contaminants such as acid gases, alkaline gases, organic vapors, or vapors of inorganic compounds. The most common application for chemical cartridges and canisters is for protection against a variety of organic vapors. When the gas or vapor contaminant passes through a fresh adsorbent bed of activated carbon, most of the contaminant is removed. As time progresses, more and more contaminant flows through the adsorbent bed without being adsorbed. Eventually, an equilibrium is reached when the challenge concentration equals the effluent concentration. The ratio between the effluent and challenge concentration is defined as breakthrough. It is often expressed in percent. For example, if the challenge concentration is 500 ppm, a 10% breakthrough occurs when the effluent concentration reaches 50 ppm. Service life of a cartridge or canister is defined as the time required to reach a specific effluent concentration.
