NOTE: The following is an article originally written for Ocean Adventures newsletter.
I don’t think I ever pictured myself as a dry suit diver. Heck, I’ve braved Bavarian winters in nothing more than a tent. What kind of man needs a dry suit for So. Cal diving? Well lately, I’ve been that kind of man and I’ve been loving it.
California diving, especially during the winter, hovers just above the temperatures that most manufacturers recommend wetsuit diving for. The general recommendation is that 50 degrees is the absolute lowest water temperature a diver should expose themselves to in a wetsuit with 60 being the realistic minimum temperature. A typical Catalina or Anacapa dive ranges from 58 in the winter to about 64 in the summer. Even with a 7mm your body chills rather quickly under these conditions. While a three-tank trip is something we can normally stand with minimal risk of hypothermia, the big advantage of dry suit diving is comfort. Let’s look at why.
Wetsuits operate by trapping a thin layer of water between you and the neoprene of the suit. Your body warms up that layer of water and the neoprene provides thermal protection between the layer of warmed water and the water outside of your wetsuit. The major difference between wetsuits and dry suits is that water is a relatively poor insulator. In order for your body to warm up that layer of water it requires approx. 20 times the amount of heat to warm an equal amount of air. Dry suits work in a similar fashion as wetsuits but they are completely sealed and they use a layer of air as their main form of insulation. In other words, it isn�t simply being dry that makes a dry suit more comfortable than a wetsuit; it’s the undergarment�s ability to trap air that keeps the diver warmer. Without proper undergarments a dry suit diver would chill much more quickly than a diver wearing a wetsuit.
Diving dry takes some getting used to. First off, once you submerge, you no longer use your BC for buoyancy control. Since you use the air in your suit to adjust your buoyancy during the dive a prerequisite for dry suit diving is good buoyancy control. You use the inflator valve on your chest to pump air into the suit which accomplishes three things; it increases your buoyancy, it provides a layer of air for your body to warm, and it prevents suit squeeze. You vent air through a valve usually located on your left shoulder. Most dry suits have an auto-venting valve that will vent air as you ascend in order to prevent a runaway ascent but you can also dump air manually by pressing down on the valve.
Because of the new techniques you must use in dry suit diving it�s recommended you take the Dry Suit Diver specialty course. Ocean Adventures throws in the course with your dry suit purchase as a way to promote safe diving. In the course you�ll learn how to care for your dry suit, the new buoyancy control techniques unique to diving in a dry suit, and how to handle potential emergencies and problems. Once properly trained you can begin experiencing the joy of being more comfortable during and after your dives which makes diving more fun and enjoyable and allows you to continue diving all year round.
If you’re still unsure if dry suit diving is for you, stop by the shop or call and ask Steve about the next dry suit specialty class. You can rent a suit for the day and try it out while you receive instruction.
