DSMB requirement?

[gfaith]

+1 @macado As the DSMB is pulled down it goes up and then drops back to the surface. It's like waving at the boat. Finish the SS and hold it straight up and wave.

 

[redacted]

I always carry a safety sausage to inflate on the surface if necessary. It's just not deployable from depth.

Almost any Cozumel DM could show you how to deploy an SMB from depth.

 

[gopbroek]

There is nothing stopping someone from putting an SMB on a reel and inflating it from depth, thereby making it or calling it a DSMB However in the event too much air is added at a significant depth you risk over-inflating the SMB and damaging it. I've seen plenty of SMBs inflated at depth without issues so this isn't always a concern, especially when inflating from a shallow depth.

I originally had a super cheap SMB without a relief valve which I attached to a finger spool and then subsequently got a less cheap Blue Reef version with a valve as a spare. I got to goofing around and tried to blow up my original by launching from 60' with full breath, no damage. Then tried 80', no luck, then 100' and again no luck but on the surface it was as rigid as a bat. I gave up as I only had a 100' on my finger spool.

 

[Dave Dillehay]

Yep,

I never busted one in 15 years being a DM (quit when I turned 60). But I never filled them all the way up and adjusted the amount of air I put in by my depth. I don't like the open bottom ones. Just my opinion.

dave

 

[scubadada]

Yep,

I never busted one in 15 years being a DM (quit when I turned 60). But I never filled them all the way up and adjusted the amount of air I put in by my depth. I don't like the open bottom ones. Just my opinion.

dave

Open bottom ones work just fine, do not leak a bit

 

[CassieNYC]

When/where is the usual time/place to learn to deploy a DSMB? I'm planning to learn in Key Largo in April provided we have calm waters. In particular, I'll be hiring a private instructor to both be the DM and help with learning the deployment skill. I want to learn so I could deploy a DSMB in Cozumel but I think I should get some practice without the current first.

 

[mstevens]

A DSMB typically has an (OVP) over pressure relief valve so that if it is shot from depth the pressure can safely escape. An SMB on the other hand does not have an OVP valve or an opening at the bottom where excessive air can escape/vent

What does "OVP" stand for?

 

[scubadada]

When/where is the usual time/place to learn to deploy a DSMB? I'm planning to learn in Key Largo in April provided we have calm waters. In particular, I'll be hiring a private instructor to both be the DM and help with learning the deployment skill. I want to learn so I could deploy a DSMB in Cozumel but I think I should get some practice without the current first.

Of course, PADI offers a DSMB employment course, 2 dives. SDI solo diver, I assume PADI self-reliant dive have the same requirement.

 

[macado]

What does "OVP" stand for?

It stands for my typo...I meant OPV Corrected.

 

[ggunn]

I agree with @Dave Dillehay you need to be slightly negative to get them to stand up straight however you don't necessarily need to carry massive amounts of extra weight at all.

Agreed. When I deploy mine I send it up from 20' or so, ascend to SS depth, and hang from it like a subway commuter. I regulate my buoyancy with lung displacement - no extra weight needed - and my sausage stands up like... never mind, I see where this is going.