Author Topic: Decompression chamber for recreational divers, can you build one? (Read 1101 times)

xr250dude · « **on:** July 14, 2008, 09:10:58 AM »

I was just wondering if anyone has specifications for a decompression chamber good enough for rec divers, even better if someone has actually built one, apart from the military. Also, where could I get the recompression/decompression protocols for DCS? I would have reckoned that DCS like any illness would largely be asymptomatic and that symptomatic DCS type I and II would be like the tip of an iceberg.

Say lah ... Use a pressure vessel large enough for a person/s that can take a max 4 bar. Pipe it with medical gasses, air and/or even O2 at 4 bar, thats the usual post 1st stage pressure for medically supplied gasses. A pressure controller to regulate input pressure along the way. A recirculating sodalime CO2 scrubbing device in the chamber much like what an aneasthetist would use. Monitoring equipment for the environment and physiological monitor for the "client".

nanda666 · « **Reply #1 on:** July 14, 2008, 11:56:25 AM »

I saw on TV recently(Globetrekkers or something) and the host, Ian Wright, was put into this "inflatable" tube which could be pressurised and acted as a hyperbaric chamber for 1 person.

Not sure if it's commercially available...will check and revert.

nanda666 · « **Reply #2 on:** July 14, 2008, 12:02:22 PM »

something like this!!

Scuba Dynamics · « **Reply #3 on:** July 14, 2008, 12:05:23 PM »

This is a version of an inflatable, one man, emergency chamber and has been available on the market for some time now and although it works to a certain degree, there are limitations of course.

xr250dude · « **Reply #4 on:** July 14, 2008, 01:13:09 PM »

I think that is more for home O2 treatment. Can only presurise till 0.3 bar above atmospheric pressure.

IkanBilis · « **Reply #5 on:** July 14, 2008, 03:05:42 PM »

Maybe can stuff a guy in a large Pelican Case, and put in pressure to 4bar.

Seriously, what is the condition of the container to sustain 4 bar pressure, must it be a steel container? The other concerns need to think of, how to switch air and how to ensure that it is delivered at such pressure? A slight mistake or miscalculation could kill the patient. The system has to be foolproof, and the supporting equipment must be small enough to be transported with the patient to a hyperbaric chamber, and transfered safely into the chamber.

xr250dude · « **Reply #6 on:** July 14, 2008, 05:06:47 PM »

I suspect not much, if we are talking 4 bar, normal water heater copper piping should suffice or even ABS piping. The copper piping used by MOX to transmit medical gasses around a hospital at 4 bar is much the same except the copper purity is a lot higher, more for quality. Likewise in dialysis units, the working pressure 30-40psi, RO water would be channeled around in ABS piping, failure usually at joints and seams or a poor weld. Steel or aluminum would be comforting though. Look at your typical Ikelite/Marine pack, its plastic, weakest point the O rings. Certainly the pressure vessel and pressure control would be the challenge. I think the CO2 scrub, monitoring equipment would not be difficult to configure based on existing equipment. Think ambulance, self contained equipment in a motorised hull.

If the patient dies, blame it on the bends

Snafu · « **Reply #7 on:** July 17, 2008, 04:11:19 PM »

Yes U can build 1....light weight(Alum), Cheap(Mild Steel)...etc.

Good luck with the design spec.

Let me know if you need help with it.

joe · « **Reply #8 on:** July 18, 2008, 12:44:29 AM »

Quote from: xr250dude on July 14, 2008, 05:06:47 PM

I suspect not much, if we are talking 4 bar, normal water heater copper piping should suffice or even ABS piping. The copper piping used by MOX to transmit medical gasses around a hospital at 4 bar is much the same except the copper purity is a lot higher, more for quality. Likewise in dialysis units, the working pressure 30-40psi, RO water would be channeled around in ABS piping, failure usually at joints and seams or a poor weld. Steel or aluminum would be comforting though. Look at your typical Ikelite/Marine pack, its plastic, weakest point the O rings. Certainly the pressure vessel and pressure control would be the challenge. I think the CO2 scrub, monitoring equipment would not be difficult to configure based on existing equipment. Think ambulance, self contained equipment in a motorised hull.

If the patient dies, blame it on the bends

well, to design the chamber, plastics (Polycarbonate) as used by ikelite should be enough but not necessary cheap as the manufacturing process will be high even though the seal design (O ring) can be improved.it resemble ikelite casing price

. plus PC is to be inert at room temp. steel or aluminum too will cost in term of material & manufacturing processes. To date, composite like fiber glass (continuous fiber winding) or other plastic matrix composite is preferable on high pressure application (e-g piping elbow for reinforcement-as stress concerntration) and yet cheaper to produce for such small volume product. last not least. the design approach itself is the most important though.can use FEA to prove. cheers

amirulhamzah · « **Reply #9 on:** September 05, 2008, 02:54:51 PM »

Quote from: nanda666 on July 14, 2008, 12:02:22 PM

something like this!!

most inflatable chamber can only give pressure to about 1.3ata (around 4psig), which is NOT to be used as a therapeutic device. The construction of these 'soft-chambers' do not allow usage with 100% O2 (usually they use concentrator). Hence, pressure wise, it's NOT sufficient to treat diving injuries; construction wise, it's NOT safe with 100% O2. Be careful, u may use it for high altitude training but certainly NOT for diving injuries.

But to build a chamber yourself, at your backyard?... hmm, some people have done it in the US, a couple of these chambers explode or get into fire; with patient inside. Well, i wouldn't want to be in these chamber. i don't supposed you'd like too,eh..?

You can get a simple hyperbaric chamber design on the web, with steel thickness, welding specs, door & hull design. In fact, it's the same standard and specification with any unfired pressure vessel (as what our 'DOSH' refer to the hyperbaric chamber). There's quite a lot of manufacturer in M'sia that can build a pressure vessel. It's just that you have to help DOSH to figure out a local standard to accept the chamber which is equivalent to ASME, DNV, Lloyd's of London etc.

Well, just to share.... Anyways, it's my first post. Hello everyone, I'm Amir from the KL Hyperbaric Center @ www.healingchambers.com.my

Decompression chamber for recreational divers, can you build one?