<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>Steve,</div><div>not the most experienced but this is what I'm doing.</div><div>I have 2 steel O2 cleaned tanks. ( 2 tanks as per GL for redundancy)</div><div>I have O2 cleaned scuba regulators & get my tanks filled at a dive shop.</div><div>Had to have an emergency O2 provider cert first.</div><div>I believe Nuytco were using composite tanks at one stage.</div><div>O2 tank options & fitting options here. (EMT medical)</div><div><a href="http://www.emtmedicalco.com/OXYGEN-CYLINDERS-ALUMINUM-STEEL-COMPOSITE_c64.htm">http://www.emtmedicalco.com/OXYGEN-CYLINDERS-ALUMINUM-STEEL-COMPOSITE_c64.htm</a></div><div>You will need a tank fitting suitable for where you intend filling i.e. dive shop</div><div>or medical O2 supplier. Then you will need a compatible regulator . If you were </div><div>heading across country for a few dives maybe have interchangeable fittings or </div><div>spare tanks with different fittings if you need to switch between medical & dive</div><div>suppliers. ( I haven't heard this discussed before) </div><div>I have heard people say that medical & commercial O2 tank swap people don't</div><div>like the idea of their tanks going under the water. They also may require some</div><div>sort of certificate from you before they fill.</div><div>Have read of deaths from people using commercial rather than medical O2, but</div><div>this would be 100% O2 inhaled straight in to the lungs.</div><div>Phil offered to sell his O2 add system to Psubbers.</div><div>I am using a paediatric flow meter set at a minimal flow & are topping up via</div><div>3 x O2 sensors wired to my PLC & operating a solenoid valve on the low pressure </div><div>O2 line. The PLC will be comparing the 3 readings & going with the average of</div><div>the 2 readings closest to each other. The PLC will notify me when the range of</div><div>one O2 sensor is out relative to the other 2 or the reading of the nearest 2 differ </div><div>by a certain amount & may need replacing. I think the life of a sensor is only</div><div>a year or so depending on the heat it is stored at. Being a small one person sub</div><div>I need to be a lot more careful as the O2 % can change a lot more quickly.</div><div>Cheers Alan</div><div><br></div><div><br></div><div><br><br><div>Sent from my iPad</div></div><div><br>On 4/01/2018, at 7:10 AM, Steve McQueen via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br><br></div><blockquote type="cite"><div><span>I tried to search the archives but it wasn't very friendly. Sorry to again ask about something I know has probably been discussed.</span><br><span></span><br><span>I wanted to double ck. my O2 strategy. After some investigation it seems I will buy a new steel high pressure oxygen tank for external mounting. My plan is to have it refilled with "commercial grade" O2 vs. medical grade 02. As long as I keep my "personal" tank and not allow the filler to swap tanks I should create a "chain of custody" that will help me feel good about not having contamination.</span><br><span></span><br><span>I am wondering how others are managing.</span><br><span></span><br><span>Thanks,</span><br><span>Steve</span><br><span>_______________________________________________</span><br><span>Personal_Submersibles mailing list</span><br><span><a href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a></span><br><span><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a></span><br></div></blockquote></body></html>