Hoods leave a diver deaf underwater.....if you have to dive in cold water, then you need to know you are diving without one of your senesce--you are handicppped.
I don't dive this way in Florida or the caribean, or Fiji...
I always hear whether or not there is boat traffic....the fact that this woman heard nothing, is absolutely consistent with what we see from hooded divers here.
If I or my group is not towing a dive flag ( which is the norm here in Palm Beach--towed flag or towed torpedo for us with flag) , and we know we are coming up well away from the other dive groups, one of us will shoot a bag....my point is that this is not done with any expectation that it will be effective in warding off boats. The expectation is, and must be, that there will be a boat coming right at you on the surface, if you hear any boats at all---and that the smb is being ignored.
So you do a nice long safety/deco stop at 10 feet--and when you feel you have the safety margin in plenty of stop time, you deflate, and kick hard to the surface, ready to perform an emergency return to 10 feet or deeper if some jerk is heading your way. If it is safe, you can wave your buddies up to the surface, and if you are concerned about bubbles from this fast surfacing, you have only been up about 15 seconds to 25 seconds total as your friends hit the surface--so you could drop yourself back down to 10 or 15 feet if you have a concern about hyper saturation. You could hang there for 5 to 10 more minutes if you needed. Keep in mind I have been doing this in my Palm Beach diving since the early 80's, and the danger has always been boaters--not bubbles.
To one other poster in this thread....we have very few sailboats out over the reefs--maybe 1 for every thousand fishing boats/speed boats. And yes, I have had a big sailboat go over head, and I saw it--rather than heard it, on my 360 degree spin. It was a shock, but fortunately the visibility was about 80 feet that day, and I saw it with time to spare in jackknifing and getting down below his keel/centerboard, whatever it was.
That was one time, in 3 decades--for the sail boat issue
The towed torpedo with a flag is by far my best defense from boaters, and best way to help my own charterboat protect us by easily tracking us. Here is one example....though I like mine alot more than this one( cona't find it this moment online)
Omersub Atoll Float
On descent, you let this out with a nice reel, and if you want to stop on the bottom, you have a hook on the reel, and can hook off on a rock or cranny.
The flag is regulation height, and the torpedo is rigged (by me) to be towed so as to float flat on the surface with the line pulling down on it, and it does so with essentially no drag at all, when compared to a standard flag float( which is very high drag). In perspective, if you toss a flag float off the back of the boat going 25 mph, it could easily rip right out of your hands, and will be very hard to hang on to....the torpedo would just fly along the surface, with very little effort in holding it.
.... to be more exact, there is a very significant "ATTENUATION" to the sound you will hear through the hood, and there are going to be some frequencies that are much more attenuated than others--which also means that your ability to recognize and use a Doppler Shift with a boat overhead, is at a major disadvantage to YOU without the hood.
