I just completed Day 2 of a 3 day water survival course at Survival Systems in Groton, CT (survivalsystemsinc.com) and I have to say this is some of the BEST training I have ever received hands down. I highly recommend anyone sailing offshore to complete this training.
The course that I'm in is actually an aviation course for aircrew. Courses are also offered for mariners. A good portion of our time is spent getting "dunked" in the pool in the ditching simulator. We then learn how to safely egress from odd angles, inverted (capsized) in the dark, holding your breath, or with an emergency air supply. We also learn how to correctly deploy and utilize a life raft, PFDs, signaling devices and how to stay attached to your crew in the water. Also we get to ride the STROP sling and stokes basket, should a helo rescue be required. All while wearing a flight suit and helmet, which is probably lighter than a warm base layer and foul weather gear. Folks, you need some strong arms to pull yourself to the surface when you're soaking wet.
Tomorrow I go to sea with my classmates and get to don an immersion suit and use the techniques learned in the pool in the ocean. Oh, they do this training year round, rain sleet or snow.
(I figured I'd write this now in case I get eaten.)
I know this hobby of ours isn't inexpensive and we will go to great lengths to save five bucks on some SS snapshackles, then spend $2,000 on a new grill, but for those of you who are like me (former medic) and like to prepare for the worst and hope for the best I offer the following:
1. This training should be mandatory for anyone contemplating spending any time on the open ocean. It's easy to think, "Oh, if I get run down by a tanker ship or swamped by a rogue wave, I'll be ok because I have a raft and an EPIRB." Well, yeah, sort of. But none of that is going to be of any use to you if you can't properly use the equipment.
2. Know every inch of your boat by feel and where the exits are. Murphy's Law dictates that when your boat is capsized, it will be while you are sound asleep in your sleeping bag in a bunk far from a hatch, at night, in cold water. I'm thinking of equiping my boat (when I finally find her) with some sort of quick release mechanism on the hatches, since it usually takes a little work to get them to open completely.
3. I will also consider carrying an emergency air supply (like a scuba type "Spare Air") on my person when on deck in foul weather (in case I capsize and am caught in the rigging) and near the berth in case the boat is capsized while off watch. Also consider marking the exits with glow in the dark tape or equipping your boat with some sort of emergency lighting.
4. A low volume scuba mask makes underwater egress so much easier (provided you have time to put it on.) It also makes fighting a fire easier since you can actually see your target clearly, so hang one near your galley extinguisher (galleys are usually a good source of fires and are usually centrally located and also near the ship's electrical panel.)
5. It goes without saying, but wear your PFD when on deck. Wet clothes are heavy.
6. Invest in a GPS equipped 406/121.5 EPIRB for the boat and Personal Locating Beacon for each crew member. You don't want to spend 117 days at sea in a raft.
Disclainer: These are just my opinions and as with all of my opinions, you get what you pay for.
For further reading take a look at Doug Ritter's website: equippedtosurvive.com.