leah:
Here are some changes I am going to make:
add 2 signal mirrors
always dive with my lights day or night (3 lights 2 led and 1 primary)
have 2 safety sausages and spools
I already notify someone on land of where I will be and when they should expect a call from me
I really would like to learn more about how to calm people in panic. The demons in their head could kill the whole group. Some have suggested joking, touching, looking into the eyes, assigning tasks and so forth.
Another random thought here, could you keep a chunk of lead one end of the weight belt and then use it like some kind of weapon to sling and hit at something unpleasant in the water? I don't know if it would work, but it might make me feel better holding it.
Here is my list of things to have and things to remember:
Safety gear -
1. SMB - Bigger is better, but at a lake or small bay, I carry a small one (regular size to everyone else). Ocean... big one.. Check it before every day of diving. I carry two on trips, just in case one breaks, but only have one with me on the dive. If you have only one, make sure it is not the type you blow up with your mouth. My buddy is my wife, and she has the same model.
2. Signal mirror - have a good one, and it does not take much room.
3. Noice maker... best you can afford. I have one of the special whistles, but I think I should add an air horn.
4. Strobe - have one on all dives.. Should be able to last more than one complete night. You can attach it to your tank.
5. Light - make it one with LED's. My pocket one would be good for days.
6. A reel, with 100 ft of line. Both the reel and the line might be needed.
If I were to go on a trip, like the Great Barrier Reef, I would carry an emergency transponder, just in case. But for diving in and around the US, would not.
I am adding anything? Yea, a large flag to be attached, if needed to the SMB - bright yellow. Does not take up much space and has no moving parts to break.
One additional thing that anyone diving should pay attention to, and it was what nearly killed me and three others - a tremendous current, one that we did not expect. And that sort of thing kills people every year. But could it have been anticipated? The answer is yes - I was just too stupid to understand it.
Currents are not mysterious, they are fairly reasonable events, that we humans tend to ignore, for the most part. They are the result, primarily from:
1. Tides - those are easy to figure. Dive the Destin Jetties, and you can see what happens when just 2 foot of water, from a bay, has to go thru a narrow openning. Oh, the bay is around 22 square miles, so two feet is....1.2 bilion cubic feet of water.
2. Ocean currents - also known.
3. River runoff - should be easy to know about.
4. Low pressure system - this is the big killer. When a low pressure system travels over water, the water directly under is under less pressure, so it raises up. Not a lot, but over say 50 to 200 square miles, it does not take a lot. For the water to go up, it has to be sucked into it. When they get near shore (in lots of miles, not our "near"), the water can only come from three directions, and sometimes less. This giant maker of big currents is what got us... a large low pressure was about 40 miles north of us, and water was rushing to get there so fast, we could not swim against it.
Knowing the above... and knowing that we are not perfect at predicting where low and high pressure centers will go, I now check to see if anything is even near and prepare for the worst if it is.
Note: High pressure can do the same thing, but usually not with the same intensity. Pushing out is not the same as sucking in.