How cold is too cold?

[jl_va_21]

So last week I signed up for a local dive for this upcoming weekend. At the time the weather (surface) was in the low 50's and the water was around 50. I dive in wetsuit(s) only and have been as low as 48 degrees comfortably. I figured I wouldn't go too deep but still realized this would be colder than that - don't mind being a little uncomfortable for a short shallow fun dive.

However since then the weather has changed. It even snowed this weekend. The forecast for my dive day is now a high of 39 degrees. I doubt this will have too much a an immediate impact on water temp but might push it a little lower. The part I wonder about this is this - even if I end the dive short, I'm going to have to get out of the water and change out of my wetsuit in cold air.

Does this still sound like some cold fun? Or is it moving into the "dangerous" realm? I'd still like to go, but want to know if that would be dumb.

I guess a related question is whether using a normal regulator (not something special for cold) becomes an issue yet - at these temps.

 

[Capt Scotty]

Being cold is no fun. If you really want to dive, I would say its dry suit time.

 

[dave4868]

It won't be dangerous if you use common sense. It won't be fun if you're cold, IMHO.

Here's what I would do to keep it fun:

• Keep warm and completely covered while setting up your gear (for 40-degree air temps, I wear a snowmobile suit, balaclava, gloves and boots)
• Submerge your wetsuit, hood and gloves into a tub of hot water that you've brought with you (in garbage bags in coolers, for example, 10 or 15 gallons will work great)
• Standing on a plastic tarp, quickly put on the suit and pour hot water into it
• If you've got to wait for a buddy, cover yourself with a plastic tarp as a wind break, unless you're getting warmed by the sun. Clear plastic might be good for solar gain and wind-break combined.
• After the dive, add hot water to the suit to warm you up
• After you're warm, take off the suit quickly and dry yourself quickly
• Quickly get back into warm clothing, completely covered
• Think about getting a drysuit and not having to do any of the above

Your regulator should be fine. I don't think it's likely to freeze up until getting into much colder conditions, such as freezing air temps and/or sub-40-degree fresh water.

Good luck! Please report back.... could be an interesting day....

Dave C

 

[SubMariner]

So last week I signed up for a local dive for this upcoming weekend. At the time the weather (surface) was in the low 50's and the water was around 50. I dive in wetsuit(s) only and have been as low as 48 degrees comfortably. I figured I wouldn't go too deep but still realized this would be colder than that - don't mind being a little uncomfortable for a short shallow fun dive.

However since then the weather has changed. It even snowed this weekend. The forecast for my dive day is now a high of 39 degrees. I doubt this will have too much a an immediate impact on water temp but might push it a little lower. The part I wonder about this is this - even if I end the dive short, I'm going to have to get out of the water and change out of my wetsuit in cold air.

Does this still sound like some cold fun? Or is it moving into the "dangerous" realm? I'd still like to go, but want to know if that would be dumb.

I guess a related question is whether using a normal regulator (not something special for cold) becomes an issue yet - at these temps.

As someone who has dove many times in those types of conditions, I can tell you that it is NOT fun to do in a wetsuit.

Dry is the only way to go.

 

[newmanl]

First off, I'd agree with Capt Scotty - those temps really are best enjoyed in a drysuit. However, that's not an insignificant expense!

Cold weather/water diving can be done in a wetsuit, there are just a few things to keep in ind in order to keep it fun, and safe. First, depending on the situation (shore dive or boat dive) try to stay as warm as you can for as long as you can before getting into the water - meaning don't stand around in the cold without warm clothes, a hat and gloves. Don't be fighting the cold before you get wet.

Next, if you do have to get into your suit some time before getting in the water, put your coat on over it while you're waiting to get in the water - if there's a delay between putting on your suit and getting in.

Once you get in the water, have fun (after the initial shock of having the cold water run into your suit is over), but end the dive when you start to shiver - shivering is an early sign of dropping core temperature.

Most people don't think of this, but while on the dive, particularly if you're not using them, your hands will cool - blood is shunted and the result is a gradual loss of dexterity. The ablity to use your hands for important tasks, or for things you'd have to be able to do in an emergency, gets compromized. End the dive before your hand get too cold to do simple gear manipulations - air in and out of BCD, clipping up a dive light... stuff like that.

For a second dive under the conditions you describe - the usual trick is to pour warm water down your suit and into your gloves right before you get back in. Although, sometimes it's just better/safer to do a single dive and be happy with that.

As for your reg, those temps should fine as long as you take a little care not to free-flow the reg (in the air, not in the water) prior to getting in.

Hope that helps.

Lee
NAUI 7908

PS: I type too slow - Dave nailed it!

 

[Codiak]

I love cold, to the point where 58 and no thermal was actually fun for a single dive.

That said... 39? dry with hood thank you

 

[jl_va_21]

I love cold, to the point where 58 and no thermal was actually fun for a single dive.

That said... 39? dry with hood thank you

39 is the air temp. In this case the water will probably be close to 10 degrees higher.

Thanks for all your comments. I know drysuit is the right answer but I'm just doing a one time experiment and this point and right at this moment (ask me again this weekend) I'm not really interested in becoming a dry suit diver. I generally look for warmer waters.

I do live on the east coast though and about half of my dives are below 60 degrees. One or two have been 50 or below. I mentioned that my coldest was 48 degrees. With my 7mm mitts and sock 2mm socks added to my 5mm boots, I've gotten to where that was pretty comfortable. In that case though, I was able to get out and warm up in the sunshine in between dives. I will not have that luxury this time, but I will only be doing a single dive for sure.

I've already thought about bringing a bucket of warm water - if for no other reason than for throwing my gear in for the drive home so that I don't need to hang out in the cold while rinsing/packing stuff like I normally would. Dipping gear in warm water ahead of time sounds like and interesting idea too, as long as I'm reading to get in the water right away afterwards. My plan is to dress warm, have some hot chocolate, and don my wetsuit in the car with the heater on.

After that, I'll just need to be conservative on how long I'm in the water - and have things prep'ed for a quick dry off an clothing change back in my heated car afterwards

Assuming I do it, I'll be sure to post a report afterwards.

 

[GSADiver]

If you aren't having fun and at least comfortable, I wouldn't dive. This is recreation!

 

[jl_va_21]

If you aren't having fun and at least comfortable, I wouldn't dive. This is recreation!

Maybe I'm crazy - but this hasn't stopped sounding fun yet! Just want to make sure I've made the necessary precautions so that it can remain that way.

 

[TSandM]

I've seen people dive wet here in temperatures like that -- it's not uncommon for our air temperatures to be in the 40 degree range for days on end in the winter, and the water will be in the high 40's, too. There aren't TOO many people who do it for long, but people do it.

As already stated, the key is to avoid losing any "thermal units" before getting in the water, and to have a ready source of heat when you get out. Hot water to pour in the suit, a heavy, windproof coat, a hat, and even some of the sodium acetate heaters where you pop the little disc and start the exothermic reaction might be good. (Those are cheap and pretty readily available.) Protection from wind is absolutely critical, as cold water is one thing, but cold water with air blowing over it is something entirely other.