DIR Details

[Deep Blue]

Lets keep this going. How about looking at decompression diving and stage bottles. Switching to the wrong gas at depth probably kills more experienced tach divers than any other cause. When diving with a DIR system, stages are labeled only one way.

The side of the tank has the MOD in at least 3 inch labels, set up so that you can read the inside label and your buddy can read the outside label. The neck of the tank has a piece of duct tape that lists the mix, date mixed, initial of analyzer, mix and MOD.

You carry all of your tanks on the left side and have the first mix you will use on top. When you make your gas switch, you

1. ID the tank from it's labels
2. Deploy your regulator, bring it around the back of your neck and hold it in your right hand.
3. Tap the purge while watching the pressure fall (You pressurized the reg and turned it off at the start of the dive)
4. Turn the valve back on place the reg in your mouth and start breathing.

You do NOT rely on the color of the second stage, which side you have the gas on, a rubber band on the mouth piece, the flavor of the mouthpiece, or any other such nonsense.

If you are using the correct aluminum tanks, you can easily dive with several 80's under your left arm without any balance issues.

Also, the regulator has the pressure gage on a 6 inch hose bent back on itself and secured to the first stage and the regulator is on a 40 inch hose, so that it fits around your neck when in use.

Speaking about the regulator, an upstream reg (Read Poseidon) has no place on a deco bottle, as if it fails, you don't get any gas. If a downstream reg has a failure, you can still use it by simply manipulating the valve for each breath. I can tell you this works because I have done it.

Also, the bottle needs to be rigged with cuttable links, ie. no metal to metal connections, so that if you jam a clip, you can still get rid of the bottle.

Well, that should get us started, please reply with any questions, or comments. If anyone would like pictures, let me know. (Of the equipment configurations that is)