{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,8,7]],"date-time":"2024-08-07T04:56:46Z","timestamp":1723006606887},"reference-count":0,"publisher":"Undersea and Hyperbaric Medical Society (UHMS)","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["UHM"],"published-print":{"date-parts":[[2017,7,1]]},"abstract":"<jats:p>Introduction: Single-hose scuba regulators dived in very cold water may suffer first- or second-stage malfunction, yielding complete occlusion of air flow or massive freeflow that rapidly expends a diver\u2019s air supply.  Purpose: This study, conducted in Antarctica, evaluated the under-ice performance of a sampling of commercially available regulators.  Methods: Seventeen science divers logged a total of 305 dives in -1.86\u00b0C seawater under 6-meter-thick Antarctic fast-ice over two field seasons in 2008 and 2009. Dive profiles had an average depth of 30 msw and dive time of 29 minutes, including a mandatory three-minute safety stop at 6 msw. Sixty-nine unmodified regulator units (17 models) from 12 different manufacturers underwent standardized pre-dive regulator care and were randomly assigned to divers. Depths and times of onset of second-stage regulator freeflow were recorded.  Results: In 305 dives, there were 65 freeflows. The freeflows were not evenly distributed across the regulator brands. Regulator failure rates fell into two categories (&lt;11% and &gt;26%). The regulators classified for the purpose of the test as \u201cacceptable\u201d (&lt; 11% failure rate: Dive-Rite Jetstream, Sherwood Maximus SRB3600, Poseidon Xstream Deep, Poseidon Jetstream, Sherwood Maximus SRB7600, Poseidon Cyklon, Mares USN22 Abyss) experienced only nine freeflows out of 146 exposures for a 6% overall freeflow incidence. Those classified as \u201cunacceptable\u201d (&gt; 26% failure rate) suffered 56 freeflows out of 159 exposures (35% freeflow incidence.)  Conclusions: Contrary to expectations, the pooled incidences for the seven best performing regulators was significantly different by Chi-square test from the 10 remaining regulators (P&lt;0.001).<\/jats:p>","DOI":"10.22462\/7.8.2017.1","type":"journal-article","created":{"date-parts":[[2018,1,3]],"date-time":"2018-01-03T17:11:41Z","timestamp":1514999501000},"page":"299-308","source":"Crossref","is-referenced-by-count":0,"title":["Performance of life support breathing apparatus for under-ice diving operations"],"prefix":"10.22462","volume":"44","author":[{"name":"University of California San Diego, Department of Emergency Medicine, San Diego, California, U.S.","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Lang","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John R.","family":"Clarke","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"name":"Navy Experimental Diving Unit, Panama City, Florida, U.S.","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"9754","published-online":{"date-parts":[[2017,7,1]]},"container-title":["Undersea and Hyperbaric Medicine"],"original-title":[],"deposited":{"date-parts":[[2022,10,20]],"date-time":"2022-10-20T20:35:18Z","timestamp":1666298118000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.uhms.org\/uhm-search\/uhm-journal-volume-44\/number-4\/performance-of-life-support-breathing-apparatus-for-under-ice-diving-operations.html"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,7,1]]},"references-count":0,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2017,7,1]]},"published-print":{"date-parts":[[2017,7,1]]}},"URL":"https:\/\/doi.org\/10.22462\/7.8.2017.1","relation":{},"ISSN":["1066-2936"],"issn-type":[{"type":"print","value":"1066-2936"}],"subject":[],"published":{"date-parts":[[2017,7,1]]}}}