Regenerable, Closed-circuit Oxygen Rebreather With Passive Torso Heating Capability

The Johns Hopkins University Applied Physics Laboratory has designed and created an alternative diving scrubber in a form of a vest that is regenerable and has passive torso heating capabilities. Regenerable, highly cyclable 5A zeolite physi-sorbents were down-selected from a number of commercial-off-the-shelf options, and sorbents of interest were implemented into the vest to scrub CO2 from the diver's breathing stream. The vest was created with high-temperature resilient, nontoxic materials featuring drop-stitch patterning to preserve form and function. The Dragon Breath rebreather prototype, including the vest, was completed through front-mount integration with the widely used military Shadow rebreather and was subsequently tested against the U.S. Navy Experimental Diving Unit technical manual specifications (TM-15-01). The vest yielded comparable endurance and work of breathing relative to traditional rebreathers with single-use scrubber materials and provided a path for tactical reusable rebreathers with passive torso heating capability.