<html>
<head>
<meta content="text/html; charset=windows-1252"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<div class="moz-cite-prefix">I know that this particular rule is
often voluntarily disregarded by hobbyists, but just FYI:<br>
<br>
ABS Rules for Building and Classing Underwater Vehicles, Systems
and Hyperbaric Facilities (2016)<br>
Section 11 (Submersibles)<br>
Subsection 5 (Access Hatches)<br>
<br>
5.3 (Operation):<br>
<br>
"All hatches are to be operable from both internal and external
sides. Hatches should be designed to seat with pressure. Hatches
that unseat with pressure will be considered based on the
application of the unit. The means for opening and closing of
hatches should permit operation by a single person under all
anticipated operating and emergency conditions. Hatches are to
have means for securing in the open and closed positions. Means
are to be available to ensure that hatches are clear of water
before opening. All hatches are to be considered when evaluating
the surface stability of the submersible. See subsection 11/31."<br>
<br>
5.5 (Pressure Equalization):<br>
<br>
"Means are to be provided for equalizing pressure on each side of
a hatch prior to hatch opening. As an alternative, an absolute
pressure indicator with means of adjusting the internal pressure
on either side may be provided."<br>
<br>
<br>
Technically, to be in compliance you need to be able to cinch it
down from the outside too. Gets to be a complicated mechanism
though.<br>
<br>
Sean<br>
<br>
<br>
On 2016-03-22 22:07, Brian Cox via Personal_Submersibles wrote:<br>
</div>
<blockquote cite="mid:20160322210749.5CE60E1B@m0087792.ppops.net"
type="cite">
<div style="font-family:Arial, sans-serif; font-size:10pt;">
<div>Hank, can you cinch it down from the inside , obviously
you would have to be inside at the time, but you might be able
to determine if it is where you want it.</div>
<div> </div>
<div>Brian<br>
</div>
</div>
</blockquote>
<br>
</body>
</html>