Unmanned Evaluation of Six Closed-Circuit Oxygen Rebreathers

摘要

Six closed-circuit (C/C) pure oxygen rebreathers were evaluated in the unmanned mode by the Navy Experimental Diving Unit in accordance with Naval Sea Systems Command Task Number 81-16. The purpose of the task was to provide performance data on existing rebreathers to aid in the selection of a new C/C pure oxygen underwater breathing apparatus (UBA) to replace the current U.S. Navy C/C SCUBA (EMERSON). Breathing resistance/breathing work studies were conducted using a hyperbaric simulator at depths up to 40 feet-of-seawater (FSW) simulated work rates ranging from light to extreme. Carbon dioxide (CO2) absorbent canister duration tests were also conducted at 25 FSW in water temperatures ranging from 29 to 90 F. Results of unmanned performance testing revealed the AGA OXYDIVE and DRAEGER LAR V C/C UBA's to have breathing resistance/breathing work and absorbent canister durations superior to all other UBA's evaluated. One exception to this finding was that the Navy 'EMERSON' exhibited canister durations slightly superior to those obtained with the AGA and DRAEGER units.