Should I check out other dive ops?

[Racer_X]

Do you really think it should be a required item of scuba gear? IMO the only required pieces for OW dives beyond the basics are an octo and a cutting tool. DSMBs definitely have a place depending on the dive, just like snorkels and lights and pony bottles and towed dived flags and gloves. But I don't think they should be a requirement for all dives.

FWIW, only a tiny fraction of all the dives ever made have been accompanied by a DSMB. Even if we restrict it to the last 10 years or whenever they started including it in OW courses, they are still only carried by a minority of divers. Are they all doing it wrong?

If you are really concerned about separation, DSMBs may not even be the best signalling device depending on conditions. And nothing compares to the effectiveness of an EPIRB or PLB in getting you found.

Ah the internet. Love those straw men.

going from "telling any diver not to carry a DSMB is something I'll never agree with" to "do you really think it should be a required item of scuba gear." Do you have to change planes in Dallas?

There's a world of difference between saying "this is required" and "I won't tell you not to to carry one."

 

[Catito]

I am heading to Cozumel in June and am staying at the InterContinental Presidente. Wondering if there is any need to venture out any try other dive operators or should the hotel's dive shop cover all my needs? I purchased a package with the hotel, so most the diving is included, but if there is anything - must see - I might miss then let me know.

The big hotels love to keep you in their walled garden but I am more than happy to go out and explore.

In my opinion, I would not use that dive operation for many reasons including the boat load of one-dive-a-year divers. We did, unknowingly, for 4 unpleasant dives, then had Aldora pick us up. 250% better dive op.

 

[ggunn]

Deploying a DSMB really isn't hard either.

Like any other skill, deploying a DSMB is easy if you know how, and you must be prepared to fail before you succeed. Waiting until you are in a situation where you really need to deploy a DSMB to attempt it for the first time is a bad idea.

 

[Charred]

Substitute DSMB for SMB in everything I have ever posted.

Are the buoys themselves any different apart from that one has a spool of string attached and the other doesn't?

DSMB have some kind of pressure release valve so they can be filled underwater and not burst when they rise.

 

[ggunn]

DSMB have some kind of pressure release valve so they can be filled underwater and not burst when they rise.

Not all of them. I replaced my 10 year old DSMB a few days ago, and it's the first one I have had with an overpressure valve. When I was shopping for it I found as many without OP valves as with them.

 

[lowwall]

By definition, if it doesn't have any way to release overpressure (typically an OPV or open bottom) then it's not a DSMB.

For example, this is from DAN

"A DSMB is technically an SMB, but an SMB is not a DSMB. Divers can deploy a DSMB on the surface or from depth thanks to an over-pressurization valve (OPV). This valve allows air to escape and relieves the gas that expands, according to Boyle’s Law. An SMB’s design, which lacks an OPV, means it should be inflated only at the surface. If you deploy an SMB from depth, it will sustain physical damage from overexpansion as it ascends."

Of course nothing prevents you from clipping an SMB to a spool and deploying it from depth. But if you get it too full, you'll end up with a burst balloon.

 

[ggunn]

By definition, if it doesn't have any way to release overpressure (typically an OPV or open bottom) then it's not a DSMB.

For example, this is from DAN

"A DSMB is technically an SMB, but an SMB is not a DSMB. Divers can deploy a DSMB on the surface or from depth thanks to an over-pressurization valve (OPV). This valve allows air to escape and relieves the gas that expands, according to Boyle’s Law. An SMB’s design, which lacks an OPV, means it should be inflated only at the surface. If you deploy an SMB from depth, it will sustain physical damage from overexpansion as it ascends."

Of course nothing prevents you from clipping an SMB to a spool and deploying it from depth. But if you get it too full, you'll end up with a burst balloon.

Whatever. My old one looked exactly like my new one except that it didn't have that valve; it had the same clip on the bottom to attach the line from a spool. I used it for more than 10 years without incident; with an oral inflator I could never fill it more than halfway at 30', anyway.

You can call it a DSMB, an SMB, or a Benedict Cumberbatch for all I care.

 

[bradStyle]

I'll make sure to purchase an SMB, don't have that on the list for this trip yet. I had a quick look and will probably just get this one from DGX along with a finger spool.

If you haven't placed your order yet I want to make a case for starting out with a smaller DSMB. 6' is *a lot* of buoy to handle. I would recommend a 4' or at most a 5' to get started, and to practice your spool work with (which is also an art form). Regarding spools, light weight is your friend. Forget those fancy (and expensive) metal ones. At some point you are likely to drop it or have it unravel on a dive. The light weight ones drop more slowly. If you are wondering where you're going to put your DSMB+spool, you could consider some dive shorts with pockets. Those contain everything nicely (including other emergency gear... whistle, signal mirror, etc.) without creating entanglement issues. Just a thought, there are many ways to solve this issue, but that's what works well for me.

I may consider doing the Nitrox dry certification before going then.

Nitrox is a great idea. Nitrogen is not our friend. Reducing it, when possible, is a good idea, if you're not going too deep for the extra oxygen that will take its place. Considering how much we spend on dive trips... travel, lodging, food, gear, operator... electing to save $10/tank on Nitrox when it may cut our NDL time way down is just not a sensible option. My 2¢.

 

[ggunn]

If you haven't placed your order yet I want to make a case for starting out with a smaller DSMB. 6' is *a lot* of buoy to handle. I would recommend a 4' or at most a 5' to get started, and to practice your spool work with (which is also an art form). Regarding spools, light weight is your friend. Forget those fancy (and expensive) metal ones.

I agree; for me a 4' buoy and a plastic finger spool is plenty. Practice deploying it when you don't really need to, like maybe on a shore dive.

To repeat a couple of tips I posted earlier:
When you get your spool, unroll the line and make sure the other end is attached to the spool; if it's not attached, if/when you drop it it's gone forever and you'll have all that string to deal with.

When you deploy your (D)SMB, don't inhale before you release the buoy; otherwise the extra buoyancy will drag you toward the surface.

If it is kept rolled up with a velcro strap, fold over and silicone glue the last half inch or so of the "vel" part of the strap so you won't be searching for the end and trying to get a fingernail under it to pry it apart when you are deploying the buoy.