An oxygen concentrator apparatus, comprising: at least two canisters (302, 304); gas separation adsorbents disposed in the at least two canisters, wherein the gas separation adsorbent separates at least some nitrogen from air in the at least two canisters to produce oxygen enriched gas; a compression system, the compression system comprising: a compressor coupled to at least one canister, wherein the compressor compresses air during operation; and a DC motor coupled to the compressor, wherein the DC motor comprises an external rotating armature, wherein the armature is wrapped around a stationary field generated by the DC motor, and wherein the DC motor drives the compressor, and an air transfer device coupled to the external rotating armature, wherein the air transfer device creates an air flow when the DC motor is operated, and wherein the created airflow passes over at least a portion of the DC motor; and a compressor outlet conduit coupling the compressor to at least one canister, wherein compressed air is transferred from the compressor to at least one canister through the compressor outlet conduit, wherein an outlet of one or more canisters is positioned such that gas exiting one or more canisters during a venting of the one or more canisters is directed toward: at least a portion of the DC motor; at least a portion of the compressor; at least a portion of the compressor outlet conduit; or combinations thereof, during use. at least two canisters (302, 304); gas separation adsorbents disposed in the at least two canisters, wherein the gas separation adsorbent separates at least some nitrogen from air in the at least two canisters to produce oxygen enriched gas; a compression system, the compression system comprising: a compressor coupled to at least one canister, wherein the compressor compresses air during operation; and a DC motor coupled to the compressor, wherein the DC motor comprises an external rotating armature, wherein the armature is wrapped around a stationary field generated by the DC motor, and wherein the DC motor drives the compressor, and an air transfer device coupled to the external rotating armature, wherein the air transfer device creates an air flow when the DC motor is operated, and wherein the created airflow passes over at least a portion of the DC motor; and a compressor outlet conduit coupling the compressor to at least one canister, wherein compressed air is transferred from the compressor to at least one canister through the compressor outlet conduit, wherein an outlet of one or more canisters is positioned such that gas exiting one or more canisters during a venting of the one or more canisters is directed toward: at least a portion of the DC motor; at least a portion of the compressor; at least a portion of the compressor outlet conduit; or combinations thereof, during use. a compressor coupled to at least one canister, wherein the compressor compresses air during operation; and a DC motor coupled to the compressor, wherein the DC motor comprises an external rotating armature, wherein the armature is wrapped around a stationary field generated by the DC motor, and wherein the DC motor drives the compressor, and an air transfer device coupled to the external rotating armature, wherein the air transfer device creates an air flow when the DC motor is operated, and wherein the created airflow passes over at least a portion of the DC motor; and a compressor outlet conduit coupling the compressor to at least one canister, wherein compressed air is transferred from the compressor to at least one canister through the compressor outlet conduit, wherein an outlet of one or more canisters is positioned such that gas exiting one or more canisters during a venting of the one or more canisters is directed toward: at least a portion of the DC motor; at least a portion of the compressor; at least a portion of the compressor outlet conduit; or combinations thereof, during use.