I've never used a DSMB and feel I need one for the equipment setup I'm putting together. I would be using it for recreational diving for now and want to keep things simple and minimal on my kit. I assume I can rig up a couple bungee loops on the side of my BP and stuff the rolled up device in there for storage.
On the topic of spool vs reel, is there a small and user friendly reel that I could use for this but also use for basic wreck dives as well and not carry two devices? Or would you recommend a compact spool solely for the DSMB for most of my dives and if I know I'm diving on a wreck, bring an extra reel for that?
Seems the color standards vary depending on location, but is it safe to say a solid orange one will be considered a standard, non emergency marker for most common situations?
What would be a sweet spot between being large enough to see on the surface but not be to much bulk on a streamlined gear setup? I'm guessing 1.5 meters?
I see most have a dual purpose valve for your inflator or oral inflation. Any pluses and minuses for the ones that have the open end with a "duck bill"? I assume that would be for exhaling into from your regulator exhaust?
I see they have an over pressure valve in case you get over zealous with inflating them. Depending on the depth of inflation, this thing is going to try and expand considerably. Is it normal for that excess air to bleed out of the over pressure valve on the way up, by design, or is the diver underinflating it at depth, anticipating expansion on ascent?
Any preference on color of line?
Since you’ve never used a DSMB, I’m going to assume you‘re not thinking of bringing along another spool with the intention of laying line in the wreck. If true, one spool and DSMB should be enough.
A reel can be a lot of line. There are some itty-bitty reels out there but they seem gimmicky to me. Halcyon makes a really trick spool that has a small handle (Defender Pro). The largest holds 60m of line which means you can shoot from 40m in a current and not get dangerously pulled up. Not critical for recreational diving (but critically important for technical diving). That 60m Defender Pro still fits in a leg pocket.
An orange DSMB is pretty universal for “Here I am decompressing / drifting / practicing” but make sure others (the captain and crew) understand what your DSMB color(s) mean. Some captains hardly ever see a DSMB so you don’t want them freaking out assuming something‘s wrong and trying to haul you up like a fish. It happens. If you let go of the spool and they come up empty handed, then all kinds of pandemonium ensues.
I think 1.5 meters is good. That will still fit in a mask pocket. I hate dangly stuff so if I’m in a stripped down ST rig in a simple exposure suit (no pockets), I put a spare mask pocket on my waist belt and carry my DSMB and spool there. Some divers have a DSMB and spool flopping all around like it’s symbolic of experience. If I tried hard, I could probably come up with a slick bungee system that doesn’t require a pocket but I’m working on other problems these days so the mask pocket works for now.
The duck bill models need to be fully inflated to ensure air doesn’t leak out. Some folks don’t like them because in a current they can start taking on water through the duckbill and displacing air out the OPV. Water-logged DSMB = not good.
When at depth, fill that sucker as much as you can without losing control of your buoyancy and let the OPV do its thing as the air expands on the way up. You want that DSMB standing proud at the surface, not wilting or trying to impersonate a carrot in the garden. I’ve seen a bunch of DSMBs only partially filled at the surface with only about half (or less) of the DSMB above the water. You don’t want that. If you find that when you surface, work to correct it at first opportunity.
Your DSMB is an effective communication device. Make sure not to mumble when you talk.
Dealer’s choice on line. I have white and orange. Both work.
