Equipment choice/procedures

[Bob Cooper]

For those of you who haven't seen it...

Have a look at:

http://www.bitz.fsnet.co.uk

for some good advice on kit/procedures etc.

Bob

[Mark Chase]

<font color='#000F22'>Interesting site but hevily bias tawards DIR kit:

Shocked at the self inflating mini cylinder blobs are dangerous comment. I personaly think they are a major step forward in diver safety.

I emailed the auther:

Interesting site, but concerned about comments on self inflating SMB's using mini cylinders.

These are a major safety improvement over conventional SMB's and I am concerned about your site raising doubt over their safety. As the Mini cylinder is totally wrapped in the SMB prior to deployment I can see no way the unit can be accidentally deployed?

The problem with conventional SMBs is mid water deployment or deployment in a strong current. Any one who has attempted to fill an SMB when the thing is flapping about like a flag in a breeze will back me up on this, Also deploying a manual SMB at the surface or near the surface is difficult. Filling an SMB to the point where it can be used to assist a flooded dry suit diver to the surface is also difficult. Gas blobs will overcome all of these issues. I personally have twice been in a situation where I was unable to deploy my manual SMB.

I do mainly wreck diving with penetration a common activity and I am reasonably sure all of my Trimix dive club use gas blobs. I have never herd of an accidental inflation. There is only one problem with gas blobs ands that is forgetting to fill them.

Mark Chase

I will be interested to see if he replyes.

Do DIR frown on gas blobs? I havent herd that yet or is that GUE havent made one yet. &nbsp;

ATB

Mark Chase

[Davey Willo]

Originally Posted by [b

Quote[/b] (Mark Chase @ Mar. 10 2003,18:57)]Do DIR frown on gas blobs? I havent herd that yet or is that GUE havent made one yet.

Ooh you cynic you!!  

[Bob Cooper]

Mark

A few points...............

1.GUE, as a training, exploration and research organisation, doesn't *make* anything.

Those self inflating DSMB's are a bad idea for the following reasons:

1. They are too bulky
2. The valve can be opened slightly, or can leak whilst stowed, leading to a potential uncontrolled ascent
3. People often *forget* to fill them
4. The small cylinders are exempt from routine tests, leading to neglect and potential failure.
5. Cracking the valve and *letting go* produces far too much lift, leading to a potential uncontrolled ascent if a reel should jam.
6. They're expensive!

A closed lift bag/SMB can be inflated mid-water, at depth or on the surface, without these potential problems. &nbsp;Guess who makes these closed lift bags/SMB's? &nbsp;yes that's right....Halcyon.

Alternatively, it's a simple matter to make one yourself, using any kind of closed SMB. &nbsp;Much simpler, safer and smaller.

Best regards

Bob

[Lawrence Debono]

Originally Posted by [b

Quote[/b] (Bob Cooper @ Mar. 10 2003,17:17)]Mark

A few points...............

1.GUE, as a training, exploration and research organisation, doesn't *make* anything.

Those self inflating DSMB's are a bad idea for the following reasons:

1. They are too bulky
2. The valve can be opened slightly, or can leak whilst stowed, leading to a potential uncontrolled ascent
3. People often *forget* to fill them
4. The small cylinders are exempt from routine tests, leading to neglect and potential failure.
5. Cracking the valve and *letting go* produces far too much lift, leading to a potential uncontrolled ascent if a reel should jam.
6. They're expensive!

A closed lift bag/SMB can be inflated mid-water, at depth or on the surface, without these potential problems.  Guess who makes these closed lift bags/SMB's?  yes that's right....Halcyon.

Alternatively, it's a simple matter to make one yourself, using any kind of closed SMB.  Much simpler, safer and smaller.

Best regards

Bob

I can confidently say DIR started in the US that's why things have to be idiot proof. That's why the US army has nice pictures of how to operate their old rocket launcher &gt; get the picture? That is exactly why DIR is against auto SMB's

The issue with leaving the tank partially open, etc is not very practical - Have you ever accidentally shut or opened the valve on your tank? Doubt it.

I use a lift bag all the time in current that is generally coming a good 400m above sea level. I'm talking about Rock Port on the St Lawrence River. It would love to have an auto SMB. I wish we could get them here. I have drifted 200 and 300 meters in 15 minutes, that's the sort of current I deal with at times and keeping steady isn't easy. We look like laundry hanging on the line at times.  Well done Mark Chase.

Take care

Lawrence

[Doug Parker]

Mark.
I done my nitrox course with a cave/RB instructor and a DIR chap and they both had Buddy self inflating blobs and those little yellow 'out of gas' Co2 blobs. Both suggested i get the same.

[Bob Cooper]

Lawrence

A fair point, but I don't understand your comment about &quot;current that is generally coming a good 400m above sea level&quot;. &nbsp;Can you elaborate on that?

Anyway, is the &quot;Empress of Ireland&quot; on the St. Lawrence river in Rimouski (?) a wreck you've dived in the St Lawrence? &nbsp;I have some buddies planning a trip there in July and I'm thinking of joining them. &nbsp;Can you let me have some info. if you know the wreck.

If I make the trip, perhaps I can bring you one of those Buddy self inflating SMB thingy's?

Thanks

Bob

[Dr Stevil]

<font color='#0000FF'>I'm with Mark on this, the only downside I can see is the extra expense, all the other caveats should be within the capabilities of anyone who is capable of diving within normal (whatever that means) parameters of &quot;Safe Diving Practice&quot;,

The only reason I don't have one is that I want to be more proficient at using the manual inflating ones before going on to the easier option. For that purpose I recently Igot one of those suit-inflators which detach to allow you to fill your dSMB, works a treat!
Downside of that option is (again) the extra expense ie new suit valve + hose = ~£70 (should have been ~80 but LDS does a 10% instructors discount)
I can highly recommend it though &nbsp;
Chee-az
Steve

[Dominic]

1. They are too bulky

They're bulky, true, but whether they're &quot;too bulky&quot; or not is surely a personal thing..

2. The valve can be opened slightly, or can leak whilst stowed, leading to a potential uncontrolled ascent

Absolute myth. When it's rolled up and secured, the valve will dump the air, and the only thing that happens is you get bubbles and an empty bottle. An uncontrolled ascent will NOT happen. Try it if you don't believe it.

3. People often *forget* to fill them

True, but that's their fault, not the product's. I haven't forgotten so far.

4. The small cylinders are exempt from routine tests, leading to neglect and potential failure.

Potentially true, but nothing stops you exchanging it for a new one periodically anyway, and you're encouraged to do so by the manufacturer.

5. Cracking the valve and *letting go* produces far too much lift, leading to a potential uncontrolled ascent if a reel should jam.

Not true. You can open the bottle as much or little as you like - if you only just crack it, it can inflate SLOWER than a half-filled SMB expanding as it goes up.

6. They're expensive!

Sad, but true.. but so is Halcyon

A closed lift bag/SMB can be inflated mid-water, at depth or on the surface

So can a crack-bottle SMB, and without all that frigging around with connecting and disconnecting hoses...

[Lawrence Debono]

Originally Posted by [b

Quote[/b] (Dominic @ Mar. 11 2003,09:54)]1. They are too bulky

They're bulky, true, but whether they're &quot;too bulky&quot; or not is surely a personal thing..

2. The valve can be opened slightly, or can leak whilst stowed, leading to a potential uncontrolled ascent

Absolute myth. When it's rolled up and secured, the valve will dump the air, and the only thing that happens is you get bubbles and an empty bottle. An uncontrolled ascent will NOT happen. Try it if you don't believe it.

3. People often *forget* to fill them

True, but that's their fault, not the product's. I haven't forgotten so far.

4. The small cylinders are exempt from routine tests, leading to neglect and potential failure.

Potentially true, but nothing stops you exchanging it for a new one periodically anyway, and you're encouraged to do so by the manufacturer.

5. Cracking the valve and *letting go* produces far too much lift, leading to a potential uncontrolled ascent if a reel should jam.

Not true. You can open the bottle as much or little as you like - if you only just crack it, it can inflate SLOWER than a half-filled SMB expanding as it goes up.

6. They're expensive!

Sad, but true..

Bob, you are right - I left it dry, let me elaborate.
This area has lakes that are about 400m above sea level. The entire system is 96000 sq miles of water. More like a fresh water inland sea. This have to come down from locks, waterfalls, rivers, etc and flow out to the Atlantic. After a cold winter like this one there would be run off from 1000's of sq km of melted snow and ice.

Could you imagine the current? It could be insane when they open the gates the St Lawrence River. I heard once that some diver using a Tekna scooter managed to find a spot with out going forward with the throttle full ahead. There are areas where the bubles from the DV go down a good 15 meters then emerge again to one side........

Currents are very evident where Superior meets Lake Huron at Sault St Marie locks and the rapids, where Lake Huron drains into the St Clair River all the way down to Lake Erie, and then there is Niagara Falls (good drift dive = don't go over!!!) to drain into lake Ontario and all that, has to pass through the straights of Rock Port and the Thousand Islands on The St Lawrence River. These are like funnel areas where water forces it self through with a fury.

Cheers

Lawrence