TheGuy(Offline)

1. - I was just doing some dive training with a non-DIR guy. He was a little critical of the technique of two stages on left side. Can someone here confirm the proper DIR technique for this skill. I was trained to do as follows and it seems to work for me.

Remove outside stage. ( ie: EAN 50 ). Clip top clip of cylinder to waist side D-Ring.
Remove and replace inside stage ( ie: O2 ).
Remove outside stage from waist side D-Ring and re-attach.

2. - What is the rational for doing this drill this way. In actual practical diving, I normally only remove the waist side clip from either stage to move the bottom of the stage to the front and replace the 2nd stage hose inside the retaining bands.

Thanks

TheGuy

ericfine50(Offline)

Check here:

Stage switching

maccajim(Offline)

I was taught unclip waist d ring spin bottle Left hand grasp bottom clip of bottle as unclip left chest d Ring. Left hand spinforward delivering bottle toward buddie showing markings. He/she places fingers in the large bolt snap gaps when has the weight of bottle release.

sorry so much easier to show in person

peter_steinhoff(Offline)

I would say there are no standardized DIR technique for this.

Why you ask? Well, first of all where you put the bottles and how you handle them would depend on what type of bottle it is, what gasmix it contains and how much gas is in the bottle. Secondly, it would also depend on what kind of dive it is (cave/ow) and in what phase of the dive you are in and the dive conditions.

The reason to put the bottles on the left are for streamlining, which becomes more important scootering or diving in high currents or flow, especially cave diving where you actually try to cover a distance not just poke around.

On a two deco bottle swimdive in the ocean I wouldn't shift anything around. I just put the O2 closest to my body and the 50% on the outside. At the gasswitch just do a 45 degree helicopter turn to show your buddy the MOD and deploy the gas. Before going to O2 you need to stow the reg on the 50%. I always do it in place without unclipping anything. The last part of the 9m / 30ft stop is a good place for this. When it's time to go to O2 just lift the 50% bottle so your buddy can verify the MOD and deploy the gas. Normally I use the O2 till we hit the surface where I hand of the 50% to the boat crew and then the O2.

If somebody wanted to practice multistage diving I would give them a variety of bottles, small ones like 40s but also 7 liters if available and of course 80s. Some of these bottles will be large or small, negative or positive and float butt heavy or butt light. I would then demonstrate and have the divers copy me while rotate these bottles around in every position that we normally use - left side, hip clipped on the left, hip clipped to a leash. I would also put an emphasize on using 80s for practice since the smaller bottles are so much easier.

That said, an instructor often has to take reality and transform it into something teachable in the alloted time frame - like a selected subset of the information that could be of use. Something to keep in mind when discussing what you where taught in class.

peter_steinhoff(Offline)

You need to change position of both the upper and lower clip if you wanted to switch places on the bottles. Otherwise you could easily entangle your bolt snaps when adding more bottles to your diving, especially if you needed to remove a bottle "in the middle".

slimer(Offline)

What about when you are in low bedding plains and if you clip the top snap to your waist Dring then the empty bottle will bounce along the celing of the cave. It is a great way to damage some formations. It should depend on what kind of dive, the amount of stages, and many other factors before you could say what is right or wrong.

SLIMER