DSMB requirement?

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wouldn/t you need a line and reel to do that though? Or not? I have always seen people using line and reel when deploying them from depth. And so far, I just haven't carried all that. Just the sausage part in case my boat doesn't find me for some reason

Definitely a line. I use a spool rather than a reel. My first spool was from a spool of fishing line which I still carry with an SMB for some trips where I do not expect to use the larger DSMB.
 
So to be clear, for beginners, would most recommend the SMB route rather than the DSMB? We just dove in Cozumel for the first time and I didn't even think about getting one. We tend to stick closer to the DM and were with Aldora so everyone was pretty close and surfaced together. From reading this site it seems that people getting separated in currents isn't an infrequent thing.

Possibly silly question: say my husband/buddy and I got separated from the group and had to come up on our own (w/out a marker). In a pinch could I inflate my BC, take off one of my fins and wave that over my head? It's neon yellow and black so seems like a boat would see that better than us just waving. I am sure there are reasons that might not be wise though. :)
 
So to be clear, for beginners, would most recommend the SMB route rather than the DSMB? We just dove in Cozumel for the first time and I didn't even think about getting one. We tend to stick closer to the DM and were with Aldora so everyone was pretty close and surfaced together. From reading this site it seems that people getting separated in currents isn't an infrequent thing.

Possibly silly question: say my husband/buddy and I got separated from the group and had to come up on our own (w/out a marker). In a pinch could I inflate my BC, take off one of my fins and wave that over my head? It's neon yellow and black so seems like a boat would see that better than us just waving. I am sure there are reasons that might not be wise though. :)

I would buy a DSMB, the main difference between the two being the over pressure valve. You can then use the DSMB by either shooting it from depth, or simply inflating it on the surface.

As far as your second paragraph, I would be careful waving your hands/ fins over your hear unless you're in an emergency situation. The waving of your arms pretty universally accepted as 'diver in trouble'. Now if I had to surface in a place like COZ without a marker, and I was bobbing on the surface waiting for any boat to spot me, I would consider taking a fin off and just holding on to it. If I saw a fast approaching boat, all bets are off and I'd start waving and flailing.
 
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As someone who teaches how to deploy a DSMB from depth as a regular part of a number of the courses I teach, I can state firmly that it is harder to do than it looks, and the danger of having the line tangle and take you to the surface with the buoy is real enough and serious enough that you should not try it on a real dive until you have practiced it several times in a less dangerous environment. For the purposes of being spotted on the surface after separation from the group, a simple SMB inflated on the surface is just fine.

As for the necessity of an overpressurization valve on a DSMB.....

I bought my first SMB about 15 years ago, and I got the cheapest one at the shop, with no OP valve. I didn't deploy it from depth for several years, when I started tech training, and I used it despite all warnings against it. I have sent that puppy up from 70-90 feet at times. Because of expansion on ascent, you don't need to get much air in it to get it full from depths like that, and I have overdone it often. I have gotten to the surface and found it to be rock hard quite a few times. No problem. I now own a half dozen bags of different sizes and styles, but I still carry that first one on basic recreational dives because it is smaller than the others and fits easily in a pocket. I also still use it for training students, too.
 
Even still, I will still argue that an SMB/DSMB laying flat is much easier to see than a diver without one.
Especially from the top deck of a boat.
 
So to be clear, for beginners, would most recommend the SMB route rather than the DSMB?

A simple, compact SMB (many come with a small whistle, that's good too) is all you need for most recreational, warm water, Caribbean diving. You should carry it on every dive (otherwise what's the point, it doesn't do you any good in your dive bag :)). Nothing wrong with getting a DSMB and spool, but practice deploying it in a benign situation. Don't be "that guy" making an underwater cat's cradle at an inopportune moment. All IMHO, YMMV. Safe diving. :cheers:
 
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So to be clear, for beginners, would most recommend the SMB route rather than the DSMB? We just dove in Cozumel for the first time and I didn't even think about getting one. We tend to stick closer to the DM and were with Aldora so everyone was pretty close and surfaced together. From reading this site it seems that people getting separated in currents isn't an infrequent thing.

Possibly silly question: say my husband/buddy and I got separated from the group and had to come up on our own (w/out a marker). In a pinch could I inflate my BC, take off one of my fins and wave that over my head? It's neon yellow and black so seems like a boat would see that better than us just waving. I am sure there are reasons that might not be wise though. :)

A couple of points to consider. An inexpensive SMB/DSMB is a lot cheaper than replacing a lost fin if you happen to drop it while waiving the fin above your head. Also, I would not advocate removing your fin to use as a signaling device unless that is your only option because you never know when you might need both fins on your feet to move quickly or swim a long distance. If you lose a fin because you didn't want to spend a few bucks on a SMB, you have really complicated your situation. Finally, a SMB/DSMB can be used as a flotation device in the even you have to ditch your BCD for some reason. FWIW, even my 14 year old grandson carries a SMB on every dive--no exceptions.
 
I can't believe anyone would surface in Coz w/o having deployed a bag from below. The boat traffic there is flat out crazy. I also think the captains should do a better job of not flying through the popular areas at wide open throttle when there are very clearly slews of divers below. After my first drive trip to Coz years ago, the first thing I learned and practiced when I got home was how to properly deploy a bag from depth. I was just down there last week and on our small boat, I was amazed that only 2 of us were sending up a bouy (aside from the DM) when time to surface. I dive an Op that lets us dive our tank/computer and surface when needed w/o the DM.
 
So to be clear, for beginners, would most recommend the SMB route rather than the DSMB? We just dove in Cozumel for the first time and I didn't even think about getting one. We tend to stick closer to the DM and were with Aldora so everyone was pretty close and surfaced together. From reading this site it seems that people getting separated in currents isn't an infrequent thing.

Possibly silly question: say my husband/buddy and I got separated from the group and had to come up on our own (w/out a marker). In a pinch could I inflate my BC, take off one of my fins and wave that over my head? It's neon yellow and black so seems like a boat would see that better than us just waving. I am sure there are reasons that might not be wise though. :)
From my experiences. All drift divers should carry some form of surface marker. For you, diving within a group, all you really need is a small easily inflated, marker. I recommend something in the 3 to 4 foot range with a closed bottom. There are many out there, here is one example...


36


If you find yourself surfacing without the guide, use the common sense precautions taught in OW, watch and listen as you slowly ascend from your stop, assess the situation on the surface, then inflate the marker if your boat isn't there or hasn't spotted you.

If you get more independent in your diving or just want to learn, you can always add a small spool or reel and start learning to deploy at depth or safety stop. In some ways it is actually easier to send from depth then from your stop.

The added advantage to shooting at depth is that you can then use it as a reference for your ascent, especially if you are a bit out of practice with drift ascents or buoyancy control.

For a little larger, open bottom for deployment at depth, this is my choice...

6ft High Vis YELLOW SMB
 
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As someone who teaches how to deploy a DSMB from depth as a regular part of a number of the courses I teach, I can state firmly that it is harder to do than it looks, and the danger of having the line tangle and take you to the surface with the buoy is real enough and serious enough that you should not try it on a real dive until you have practiced it several times in a less dangerous environment. For the purposes of being spotted on the surface after separation from the group, a simple SMB inflated on the surface is just fine.

As for the necessity of an overpressurization valve on a DSMB.....

I bought my first SMB about 15 years ago, and I got the cheapest one at the shop, with no OP valve. I didn't deploy it from depth for several years, when I started tech training, and I used it despite all warnings against it. I have sent that puppy up from 70-90 feet at times. Because of expansion on ascent, you don't need to get much air in it to get it full from depths like that, and I have overdone it often. I have gotten to the surface and found it to be rock hard quite a few times. No problem. I now own a half dozen bags of different sizes and styles, but I still carry that first one on basic recreational dives because it is smaller than the others and fits easily in a pocket. I also still use it for training students, too.

Yeah--I went and watched some YouTube videos and it looks tricky--something I would want to practice before attempting to use. I will investigate and get one or the other and then make sure I get a trial run or two in. Could you practice in a dive shop pool or is that too shallow to really get a feel? I am in Colorado and not a cold water diver so until my next vacation I won't have an opportunity. Thanks!
 

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