Quick tune-up dive at Lake Jocassee (upstate South Carolina) today. Water temp was a brisk 61 degrees, but I was generally fairly warm. Used a Bare 3mm Thermal Vest with 7mm integrated hood, and also a Bare 7mm Artic Full suit. I really like the way the suit fits (kinda tight), but also limits water circulation (= warm). The hood has a skin-type seal around the inside of the face, and the vest and suit are made to go together with a small flap covering the neck of the full suit. Also used 5 mm Henderson Insta-dry gloves (really warm as well), and Henderson 3mm boots.
Overall dive was about 40 minutes, with max depth of 57'.
At the end of the dive, decided to deploy my Surface Marker Buoy (SMB - actually an OMS 75# Lift Bag) since I had not deployed it in over a year. Bag deployment was a little tricky because of the thick gloves. I keep the SMB rolled up and bungied under of my backplate and clipped off to the rear D-Ring and my OMS Reel inside my right BC pocket. At about 30 feet, connected the reel to the bag, shot some air into it, and off it went. Noticed that it did not seem to keep much air in it, and when I surfaced after my safety stop I noticed that the exhaust valve had popped loose, holding only a small amount of air in the bag.
The important lesson is that you should set training objectives during your dives to test your equipment and make sure that all components function properly. The SMB can serve as a critical piece of rescue equipment during emergency situations (as an alternate flotation device), or when you need to surface away from the boat and are in current and off the Mooring Line.
