Evaluation of Modified Draeger LAR V Closed-Circuit Oxygen Rebreather. Part I. Unmanned Testing. Part II. Manned Testing
Abstract
The modified Draeger LAR V closed-circuit oxygen rebreather was evaluated by the Navy Experimental Diving Unit to determine its suitablity for U.S. Navy use. Previous evaluation of the German-made scuba in its standard configuration found the LAR V technically satisfactory with adequate reliability and maintainablity characteristecs; however, the clockwise oxygen flow in the breathing loop is the reverse of all U.S. Navy scuba equipment. The manufacturer modified 10 units for further NEDU testing. Unmanned CO2 canister duration tests resulted in canister breakthrough after 48 minutes in cold (39 F (4 C)) water and 3 hours and 15 minutes in warm (70 F (21 C)) water. LAR V breathing resistance values at light, moderate, heavy and extreme diver work rates were acceptable. In view of the short unmanned canister durations experienced in cold water, a series of 24 manned dives was carried out in the OSF wet pot at 25 FSW in 70 F (21 C) and 40 F (4 C) water. Canister outlet carbon dioxide levels, breathing resistance, and oxygen consumptions were measured. Mean canister duration was 226 + or - 23 minutes and 124 + or - 9 minutes in 70 F (21 C) and 40 F (4 C) water respectively. Breathing resistance was acceptable at all work levels, and no other design limitations were encountered. Differences in unmanned versus manned canister durations in cold water may be partly attributable to slightly higher carbon dioxide injection rates during unmanned testing.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1979
- Accession Number
- ADA077451
Entities
People
- Claude A. Piantadosi
- James R. Middleton
Organizations
- United States Navy Experimental Diving Unit