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<div dir="ltr" data-setdir="false">Rick,</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Besides others, Steve McQueen ran that scenario in his K250 and reported on it at PC2021 in Orlando. In a sealed hatch test without O2 or scrubber, he reached 5000ppm in 14 minutes and 10000ppm in 30 minutes. The O2 had depleted to 19.5% at 34 minutes.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">You have slightly more volume in your K350 but should find similar results. In the old days (before these measured tests) we used to say you could stay underwater in a K350 for about 30 minutes before surfacing to refresh the air inside, which seems to be confirmed by Steve's tests. Important to understand that Steve's test represents one person, at rest with no stress. Adding a passenger, moving around, and/or stressful situations will increase your breathing rate and reduce time to max/min levels. </div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Jon</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false"><br></div><div><br></div>
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On Wednesday, May 28, 2025 at 10:30:52 PM EDT, Rick Patton via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div id="ydp7e631161yiv2728931813"><div><div dir="ltr">Does anyone remember who sat in their sub with the hatch closed to see how long they could stay before the Co2 PPM became dangerous?<div><br clear="none"></div><div>Rick</div></div><br clear="none"><div id="ydp7e631161yiv2728931813yqt80677" class="ydp7e631161yiv2728931813yqt1274729295"><div class="ydp7e631161yiv2728931813gmail_quote ydp7e631161yiv2728931813gmail_quote_container"><div dir="ltr" class="ydp7e631161yiv2728931813gmail_attr">On Fri, May 23, 2025 at 9:22 AM Rick Patton <<a shape="rect" href="mailto:satwelder@gmail.com" rel="nofollow" target="_blank">satwelder@gmail.com</a>> wrote:<br clear="none"></div><blockquote style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex;" class="ydp7e631161yiv2728931813gmail_quote"><div dir="ltr">Someone posted a while ago that they sat or layed in their sub until the PPM got dangerous.<div>Can't remember who that was? Wanted to get more information from them if possible.</div><div>Thanks</div><div><br clear="none"></div><div>Rick<br clear="none"><div><br clear="none"></div></div></div>
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