Another long reply coming up
Originally Posted by Nos4r2
Doug, just a thought. What do you think of the idea of wearing light ankle weights (not enough to give you negative bouyancy) with a drysuit and a 150n LJ?
Never come across it other than for divers (where they do have negative buoyancy) but I would have though that if the weights were not negatively buoyant (i.e. heavier than water) they would make no difference. Remember removing as much air as possible is important when using a dry suit
Originally Posted by Jelly
I remember being told that you should only use a 275N LJ if you are carrying heavy equipment on your person or heavy oilskins / Dry Suit as it needed the mass to right the body + LJ to the correct orientation.
I was told that some tests had shown very lite people with little clothing in a 275N would not right and could be floating inverted and unable to right themselves due to the buoyancy forces. I'm pretty sure this came from one of the cold water survival researchers at a conference.
I would be interested to hear/read some more details on this. From memory the standard 150N are designed for adults and teenagers (over 40 kilos, this may vary slightly with different manufactures) I think this is the same for the 275N (will check and confirm/correct this on Monday). That said I would not advocate someone slight wearing a 275 unnecessarily as once inflated it is enormous and very difficult to then climb into a raft/RIB/marina pontoon etc. As already said itís about having the right kit for the right situation.
The generally accepted practice in the leisure world is to wear a 275N if you fall into one of these categories.
ē Single handed operator (therefore unlikely to have survival craft nearby).
ē Particularly heavy people (we are talking twenty something stones).
ē Those wearing heavy tool belts or similar.
ē Those wearing dry suits or rubber sealed ankles where large amount of air can be trapped in the legs.
ē Operating in an ocean environment where the expected wave height is bigger
This list is not exhaustive but a guide. Most commercial users wear one; this is as a result of HS risk assessments. The RNLI wear them. I donít want to sound like Iím belittling the 275 because it has its place but it is slightly heavier and bulkier to wear, it is massive once inflated and itís more expensive (not wanting to start the cost vs. human life debate).
One of the biggest benefits I see of the 275N is that many manufacturers make it with two lungs; therefore if one was damaged there is effectively a back up. The 2nd lung has an independent canister and firing system.
I would suggest for inshore leisure RIB users who are operating with others on board there are other safety devices that may be more worthwhile for your money (the hood and crotch straps already mentioned being two of them) and that regular servicing and inspection is particularly effective.
Iíve got a 275 and a 150, I wear the 275 rarely. I have thoroughly experimented with my dry suit/LJ combo and found it worked for (up righted) me. We are of course all different.
I have seen numerous students on Sea Survival Courses whose 150N life jacket have failed to turn them upright, ignoring the dry suit guys this has nearly always been due to a badly fitting (too loos) LJ and/or no crotch strap. WE have a contract with a local fire brigade for Sea Survival training, as they all turn up in heavy duty dry suits with integral wellies I have had to buy some 275 specifically for them for the pool.
We did have one girl, must have weighed about 55kg who would not right from a 150N, she told me she carried 14kg weight when diving in the Red Sea (which is loads more than I carry at approaching twice her weight). So there are always people that are different.
Originally Posted by JSP
I always thought jeans would be good to keep warm as long as kept dry so I'm glad you've pointed out they aren't. No cotton too? Will have to remember that.
For future ref does anyone know the BEST type of normal day (as in stuff you can go to asda and pick up) clothes to wear, what fabric etc?
The best first layer (next to skin) would be treated polyester or silk, There are plenty companies that make good thermals, you might find the ski and outdoor stores slightly cheaper than some of the yachting branded stuff. A very thin pair of socks is good as well as are some very thin gloves.
The next layer can be heavier poly or fleece. A lot of people got for roll neck and long sleeves. I have been over the years issued loads of crap fleeces by outdoor centres and sailing schools I used to work at. For about 10 years I have only worn Mustso, Iím not saying there are the only or best brand but they work. I have had students who have bought cheap high street fleeces and get cold very quickly, I think itís because the stitching is not close enough. Musto do a mid layer called shell, its very thin and tight fitting. I bought one after the Round Britain and Ireland Race (got very cold in 06) and it is what I wear in the winter under dry suit or oilies. In olden days sailors wore wool, still good but has been overtaken by many man made fabrics.
Several thin layers that do not restrict movement is the answer, have a look on the websites of Musto, Henri Lloyd, Gul, etc they will explain it more accurately than |I have.
Originally Posted by JSP
with you saying about getting the right buoyancy, to tell the truth I'm a cat funt by way of beer bellie, so most of my weight is lower down (I'm sure I'm hung like a donkey too but haven't seen it since I was 18 and doing weights
) So taking into account I'd have clothing on, dry suit with light sailing boots on, would the 275N be best for keeping my head out?
Itís not about keeping your head out, it more about the turning effect of an unconscious casualty. A well fitted 150 would probably do the job, but see above. There is no harm in trying it out on the slipway next time you are launching. Hold your breath lay face down, go as relaxed/limp as you can and see what happened. If it does not turn you face up then do it yourself and go shopping. Every person is different but a well fitting 150 works for most.