Canister Mask : A breathing apparatus that uses a canister to filter toxic mists and dust from the atmosphere; it is no longer recommended for fire service use because it cannot be used in an oxygen deficient or very hot atmosphere
Ralph W. Burklin & Robert G. Purington, Fire Terms: A Guide to Their Meaning and Use, National Protection Association, Boston, MA 1980 USA. (Guide: Meaning and Use, Nat Prot Association Fr Srvc - Amer) {457}