DSMB size - is 6’ overkill ?

[Lorenzoid]

There are some old threads speculating on how far away SMBs of various sizes are visible to boats, some posts contributed by boat captains, if I recall. There was also speculation on how well those supposedly radar-reflective strips that some SMBs have work. My takeaway from those discussions was that a minimum of 6 feet is the best option for the open ocean. Ideally, carry both a large and a small. The small can be for deploying from safety stop depth, while the large can be for inflating on the surface if you surface and don't see the boat.

I MIGHT use a 3 ft in high traffic dive areas like Cozumel. There are always boats around, and I think they are reasonably vigilant about spotting SMBs. In most places, sadly, boats are NOT vigilant and could very well run you over if they don't spot your SMB.

In my opinion, you don't even need a spool/reel if your purpose in carrying it is to launch it from safety stop depth (or on the surface). I have seen some SMBs with attached 20-30 ft. leashes--no spool or reel at all. Having tried that, I'm not sure a leash is actually easier to handle than a spool, assuming one has a little practice. Obviously a spool/reel gives you more flexibility. Some wreck divers consider the contingency plan of tying in to the wreck and using the line up to the SMB to ascend.

 

[Dan]

@RyanT , would you have a picture or can you tell me a little bit more about this setup? I’m not understanding this. Thanks.

Here is mine. 6’ DiveSmart w/ 100’ spool. Got it from Amazon. Not bulky at all. Fit nicely in my BCD pocket.

I have dedicated low pressure hose with this nozzle, below, to blow air quickly into the DSMB at depth without the need to take my regulator off my mouth.

You see the red hose coming out of my 1st stage regulator, below? That’s the low pressure hose with the air nozzle for blowing the DSMB quickly.
Easy peasy

 

[Dogbowl]

Here is mine. 6’ DiveSmart w/ 100’ spool. Got it from Amazon. Not bulky at all. Fit nicely in my BCD pocket.
View attachment 444498

I have dedicated low pressure hose with this nozzle, below, to blow air quickly into the DSMB at depth without the need to take my regulator off my mouth.
View attachment 444499

You see the red hose coming out of my 1st stage regulator, below? That’s the low pressure hose with the air nozzle for blowing the DSMB quickly.
Easy peasy

View attachment 444500

I see! I will need an extra hose for this setup. Thanks!

Is the nozzle universal? Like, do most such nozzles fit most SMBs?

 

[Dan]

You need the quick-connect fitting on the back of the nozzle so you can snap it on the low-pressure hose.

I chose the small tip so it can fit into the ID of the DSMB nozzle & won’t waste compressed air out to the ambient while you are trying to fit the tip to the DSMB nozzle in a hurry.

I used to use one of these (below). Not good! Wasting my air & not easy to mate the tip into the DSMB nozzle. It’s now in my drawer, collecting dust.

 

[Dogbowl]

Can I assume people think closed SMBs with OPV is the way to go? As opposed to open bottom?

Currently, the Halcyon 6’ Slim seems to be a front-runner but the cost is killing me!

 

[Lorenzoid]

I'm not familiar with many SMBs, but the "open bottom" of the DAN SMB has a duckbill valve, so that air doesn't escape regardless of whether you choose to inflate it from the bottom or through the inflator valve. I don't see how that kind of open bottom would be a disadvantage. Rather, it seems to me it would give the diver more flexibility.

 

[Dan]

I used to have open bottom SMB, but I quit using it due to:
1. It would flop flat on the surface once it breaches the surface. So it’s useless as a marker, unless you are on the surface & keeping the open bottom underwater & refill the SMB with air.
2. It’s a pain in the a*s to dry out the wet inside once you are done with it & want to pack it for traveling home. I had to roll small towel & shove it into the 6’ deep hole.

A lot easier to dry up the SMB with closed bottom. Once the outside is dried under the sun, you just bleed the air off the nozzle while rolling it up. Easy Peasy.

 

[wKkaY]

For ocean dives i carry both the 3' and 6' smbs.

I typically shoot the 3' from depth. The 6' is stowed without line/spool attached. I intend to only inflate it at the surface if I really need the extra visibility. It's also the smb I lend to an instabuddy who doesn't have one.

 

[smokn']

Hog! 6ft Orange SMB w/ Reflective Tape , Piranha Dive Shop |

DGX Custom - Stainless Steel Finger Spool

Got this combo recently with the spool in medium. Can’t say enough good things about it. It rolls up almost as compact as my safety sausage.

 

[CuzzA]

2-3 foot seas are about the average for decent weather. So consider your 4 foot smb is submerged by a foot, there's sunlight reflecting off the waves, if there's a good wind blowing it could be white capping a bit, and just like that, you can't be seen from a few hundred yards away.

I used to carry a 4' and an 8' in the ocean. My navigation is so much better these days I only carry the 8 footer. I have a lift bag pouch/sleeve under my wing where I keep the SMB and PLB. It's out of the way.

8 Foot High Viz Orange SMB

XS Scuba Lift Bag Sleeve

ETA: After adding a Dive Alert I rarely ever have to deploy an SMB.