At what water temp can I start diving wet in a 7mm suit

[CT Sean]

You should also look into a good hood or hooded vest as about 80-90% of your body heat is lost through your head. Another factor would be what you are doing during a dive. If you are working you will stay warmer then if you are just slowly swimming around.

The "80-90% heat loss through your head" is a myth, but the hood recommendation is valid regardless. I can't imagine diving even in 70* water without a hood. My junky 7mm fullsuit is only good to high 50's, I've been in water down to 38* with it, but I didn't enjoy being there and didn't last very long.

 

[drdaddy]

Up until last yeat I wore a 7mm wetsuit throughout the winter (and Lake Ontario gets pretty cold in winter). I was able to do around 30-40 minutes without getting too cold (uncomfortable but not hypothermic). I made the decision to get a drysuit when I realized that if something went wrong on the dive and I wasn't able to get out of the water when scheduled...OOA that resulted in a long surface swim or assisiting my buddy if they were in trouble, cramping etc., then I would be in real trouble.

So, yes I was fine diving wet all winter as long as everything went according to plan but I realized that 15 extra minutes in the water might be the difference between a safe dive and a tragedy.

Bob (Toronto)

WOW - what was the temperature? Sounds a lot colder than what I was talking about. When I was writing about 7mm wetsuits for 2 dives, I was talking about 48 degrees Fahrenheit (8.89 Celsius). At the end of the second dive I even choose to do a long surface swim looking at the scenery and waving back at the seals!

 

[tracydr]

I dove wet in Puget Sound my whole first year of diving. I was fine to 45 degrees with heavy hood, thick gloves and a double suit ( I think it was 12-14 ml at the core). That said, I was always looking longingly at the drysuit divers. Getting out of the water dry is so nice when it's chilly and raining!
I now have a drysuit but I would do those same dives again wet, if that's all I had.
(wishing I lived there again!)
I love cold water diving, west Coast, anyway.

 

[infoleather]

When it's cold, I'm sometimes a bit cold after diving first, but so rarely uncomfortable.