<table cellspacing="0" cellpadding="0" border="0"><tr><td valign="top">Alan<br/><br/>No definitive answer but we can postulate that both sensing and actuation are involved. <br/><br/>On sensing, differential pressure on either side of the hatch is translated to a impulse to actuation.<br/><br/>On actuation, a method of locking out the operator from physically un-dogging the hatch, is the only way to meet the standard as per your O.P.<br/><br/>Joe<a href="http://overview.mail.yahoo.com?.src=iOS"><br/><br/>Sent from Yahoo Mail for iPad</a></td></tr></table> <div id="_origMsg_">
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hank pronk <hanker_20032000@yahoo.ca>; <br>
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Personal Submersibles General Discussion <personal_submersibles@psubs.org>; <br>
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Re: [PSUBS-MAILIST] G.L. summary Pressure Hull <br>
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Wed, Dec 11, 2013 2:36:26 PM <br>
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<td valign="top"><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12pt;"><div><span>Alan,</span></div><div><span>Is this equalization from overpressure inside the hull? or external pressure. </span></div><div><span>Hank </span></div><div class="yahoo_quoted" style="display:block;"> <br clear="none"> <br clear="none"> <div style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12pt;"> <div style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12pt;"> <div class="yqt1385517701" id="yqt07881"><div dir="ltr"> <font face="Arial" size="2"> On Wednesday, December 11, 2013 1:23:21 AM, Alan <alanlindsayjames@yahoo.com> wrote:<br clear="none"> </font> </div> <div class="y_msg_container"><div id="yiv6100496818"><div><div>Can
anyone enlighten me on what sought of mechanism</div><div>is used that renders the opening of the
hatch possible only after</div><div>equalisation, as per G.L. Requirements?</div><div>Thanks</div><div>Alan<br clear="none"><br clear="none">Sent from my iPad</div><div class="yiv6100496818yqt6118645076" id="yiv6100496818yqt49514"><div><br clear="none">On 11/12/2013, at 3:01 PM, Alan James <<a rel="nofollow" shape="rect" ymailto="mailto:alanlindsayjames@yahoo.com" target="_blank" href="javascript:return">alanlindsayjames@yahoo.com</a>> wrote:<br clear="none"><br clear="none"></div><blockquote type="cite"><div><div style="color:rgb(0, 0, 0);font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:14pt;background-color:rgb(255, 255, 255);"><div>Hi,</div><div>I'm not covering much in this section because if I started on construction</div><div>regulations, I would just be duplicating what was printed.</div><div>G.L. wants you to have manufacturer certificates for every non structural
screw.</div><div>Any company you contract to do your welding has to have their facilities, personal</div><div>& supervision approved by G.L..</div><div>Some points of interest are.... hatches need to be opened from both sides, they need</div><div>to be able to be secured open, they need to be designed in a way that opening of the</div><div>hatch is only possible after equalization. Two measures are required to guarantee that</div><div>the hatches are closed & secured before diving; one measure is to be visibly noticeable.</div><div>Mechanical
measures for stopping a banging of the hatch is required.</div><div>Any external through hulls are to be protected against damage by appendages or covers.</div><div>If you are doing calculations on a computer you have to prove that the program is suitable.</div><div>Alan</div></div></div></blockquote></div><blockquote type="cite"><div><span>_______________________________________________</span><br clear="none"><span>Personal_Submersibles mailing list</span><br clear="none"><span><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="javascript:return">Personal_Submersibles@psubs.org</a></span><br clear="none"><span><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a></span><br clear="none"></div></blockquote></div></div><br clear="none"><div class="yqt6118645076"
id="yqt62748">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="javascript:return">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br clear="none"><br clear="none"></div></div> </div> </div> </div> </div></td>
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