Decompression stop for shallow dives?

[The Kraken]

And the question is . . . ???
"Decompression stop for shallow dives?"

I know I'm guilty of getting off the subject, but now we're talking about SMB's . . !?!?!

 

[dbulmer]

For the type of diving I do ie shallow dives less than 18 metres a safety stop is required 1) The dive tables I use require it and I follow the plan 2) it's good discipline to perform the stop as all dives are decompression dives by the tables I use (SAA Buhlmann) 3) DSMB usage comes into play as I'd be deploying it shallow.

TX,
One final comment and then (Kracken I'll shut up) it's not been my experience so far to get tangled because I don't allow to be that slack for any amount of time but I'd be lying if I said I was competent with it.

 

[jbd]

My biggest question, I guess, would be; Why don't the texts stress the same attitude?

The NAUI text does include a precautionary decompression stop at 15 feet for 3 minutes as part of ascent training. Such a stop does doing exactly what BigJetDriver mentions--it slows the rate of ascent to the surface. IIRC from one of Weinke's books, it effectively cuts the ascent rate in half compared to a 60fpm ascent which used to be the standard. The more common ascent rate taught now is 30 fpm. The stop will still enhance risk reduction. While we want people to have the least amount of risk possible, we don't want the new or unexperienced diver to worry about making a non mandatory stop if they are experiencing trouble or having problems for which being at the surface would be the safest place for them to be.

 

[fmw625]

Air will escape from the BCD vents as long as the vent is above the air. I learned this the hard way. In the beginning I was using too much weight and venting was not a problem from any orientation. As I dropped weights and inflated less I started having problems venting air. In an attempt to fix my problem I have learned to place a vent at the highest point when venting if I want to get all the air out. This is probably not standardized on all BCD, so you need to be familiar with your BCD vent locations. Just my 2c.

 

[Buoyant1]

PADI OW manual sez.."60 feet per minute, (slower is fine)"

Clay Coleman's book as well as Karen Berger's sticks to 30 feet per minute rule. (actually Berger's says no MORE than 30 fpm!)

One thing I've wondered about, is why ascend vertically? (as in your direction , not attitude) wouldn't a diagonal ascent help you to control the ascent a lot better?

 

[jbd]

PADI OW manual sez.."60 feet per minute, (slower is fine)"

Clay Coleman's book as well as Karen Berger's sticks to 30 feet per minute rule. (actually Berger's says no MORE than 30 fpm!)

One thing I've wondered about, is why ascend vertically? (as in your direction , not attitude) wouldn't a diagonal ascent help you to control the ascent a lot better?

In my classes I teach 30fpm or slower. A diagonal ascent would make it easier for many people to slow their ascent rate when doing a shore dive since they have the terrain as a visual reference and some things to see to occupy that time.

If you are boat diving, then a vertical ascent is probably the way to go so you are in close proximity of the boat when you reach the surface.

Using very slow ascent rates for shallow dives, I don't think decompression stops are needed and one could probably make a case for not even considering a safety stop at all.

 

[RichLockyer]

For the valve to be at the highest point you have to be off-horizontal. Either head slightly up or slightly down - otherwise the air isn't at the highest point!

Even if you do lack the skills to properly operate the wing, or when diving a drysuit, you are under the misunderstanding that DIR divers are always 100% perfectly horizontal at all times while underwater.

That is yet another misconception.

A SLIGHT tilt to the side, or head down or head up, is not going to throw your trim off and result in enough of a reduction of resistance to the water column to promote the beginning of an uncontrolled ascent.

DIR divers look under ledges, they swim down to grab a lobster, they clean rudders and props... they do all kinds of things that you can't do when perfectly horizontal.