If you are anything like me, you'll be doing most of your diving in Canada, and if there is one thing about local diving that any diver knows: the waters here are COLD!
Exposure suits in Canada are a must to maintain some warmth while diving by slowing down heat loss. Body temperature quickly decreases when submerged in water (even in the tropics), and we are at risk of hypothermia without the right gear. A common question asked by divers is what is the difference between different exposure suits.
A wetsuit provides thermal protection for divers and works on the principle that your body is the best heat source. Wetsuits are made with a closed-cell foam material (Neoprene) filled with thousands of tiny gas bubbles trapped within the structure. Once you enter the water, the material allows a thin layer of water through the suit, filling the space between your body and the inner layer of material. This layer of water warms up using your body temperature and helps keep you comfortably insulated throughout your dive. A wetsuit also has to be thick enough to suit the temperature of the water you're diving in
On the other hand, as the name indicates, a dry suit keeps you completely dry by ensuring that no water gets in contact with your body. It can be made out of neoprene, crushed neoprene, vulcanized rubber, or heavy-duty laminates. Drysuit uses a combination of wrist seals, a neck seal, and a waterproof zipper to keep you dry. Drysuits fit more loosely than wetsuits and allowing you to wear clothes or other insulating layers underneath.
Coldwater diving is the most challenging and the most exciting type of diving you experience. In Canada, we have some of the best-preserved shipwrecks, drift diving, great wall diving sites and, of course, for the few brave ones – ice diving. A place like British Columbia or Newfoundland offers an abundance of marine life full of vibrant colours.
I've been diving for over 8 years, most of it in a 7mm wetsuit and most of the time, it did a spectacular job keeping me warm. However, you reach a point where enough is enough, your machio posture is gone, and the bone-chilling cold finally gets to you, especially between multiple drives on the same day.
We all have been there: you start the day with a plunge from a shore or a boat dive. You observe veterans pouring warm water from a thermos inside their wetsuits, and before the second dive, as you're shivering to stay warm, and you wish you thought of the thermos too.
After lunch, you join a group for a two-tank boat dive. You lug all your soaking wet gear to the boat, and that's where the fun begins. You reach into your bag to pull out your very wet and heavy wetsuit that doesn't want to slide back on your body, but you keep saying that you are a diver and divers are a tough breed, plus everyone on the boat is watching each other. Next come soaking wet boots, gloves that don't want to fit your hands and my personal favourite: the dripping wet hood.
Depending on the weather, you are slowly cooking inside the wet suit, waching steam rise from the surface, or you are shivering as the body fights to stay warm.
Finally, you take a giant stride off the boat, and you plunge in the coldness of the water, which only amplifies the unpleasant sensation.
During the descent (depending on the location and the time of the year), you are most likely to encounter a thermocline. This shimmering layer is where the warm and cold water meets, and you swim through it, your body experiences a shock that's hard to describe. Your blood vessels constrict, your heart rate goes up as the body is fighting to stay warm, and your breathing involuntarily accelerates. As you approach the destination, you get immersed in the experience. The discomfort is quickly forgotten, but as you continue to descend, your wetsuit compresses, and you feel the cold again.
The reverse trip to the surface through the thermocline is comparable to swimming into a hot jacuzzi and feels incredible.
Back on the boat, as you wait for the second dive, hopefully, you pulled down your wetsuit to warm up. Otherwise, your body continues to lose heat, and the next dive is bad, cold and not fun at all.
Over the years, as you continue to explore Canadian waters, to make the experience more pleasant, you change elements of your exposure suit: add thicker gloves, maybe a 10 mm hood or maybe a different wetsuit. These upgrades worked for me, allowing me to reach some of the deepest wrecks in Tobermory semi-comfortably. But despite all upgrades, my heart always raced, trying to keep up with the +4C (40F) surrounding temperature, affecting my air consumption.
Adopting a drysuit changed my experience forever for several reasons:
They are more comfortable and easier to put on than a 5 or 7mm wetsuit.
A drysuit completely seals you from the external environment, keeping you warm, dry and comfortable even in the coldest water.
All over a sudden, your dive season is longer, and you are no longer limited to the warm summer and fall months. You dive more, and you dive year-round with more comfort and joy while exploring new locations.
Becoming a drysuit diver allows you to expand your boundaries and maybe even celebrate a new year with a plunge into frigid waters.
If you want to stay warm, enjoy every drive in cold waters and expand your dive season, it is time to consider diving dry.
Before you invest in a drysuit, I strongly advise you to visit your local dive shop and try different suits by renting them. There are big differences between tri-laminates and crushed neoprene construction, which affect your buoyancy, comfort, the type of undergarments needed to stay warm, and the cost. Do your research, find the type that you feel comfortable with and that meets your budget. With an average lifespan of well beyond 10+ years, a well-maintained drysuit easily outlasts a typical wetsuit. Hands down, a properly fitted drysuit and appropriate underwear give you the ability to dive in any thermal environment more comfortably and more enjoyably than a wetsuit.
If you decide to switch to drysuit diving, don't forget the training. Maybe you have been diving for a long time, but you need to learn and master new essential skills:
· Putting on and taking off your drysuit independently and with minimal assistance from your buddy.
· Learning buoyancy control and mastering it over time (yes, you need to learn this skill again)
· Mastering safety procedures
· Learning how to maintain and store your drysuit to maximize its lifespan.
I guarantee that your first solo dive in a drysuit will be awkward: with the buoyancy all over the place, trim completely off as you are trying to distribute the air inside the suit and, yes - the task loading.
Back on the boat, you are warm, dry and happy, looking forward to the next drive to master the new skills and explore more dive sites.
I am still keeping my trusted wetsuit for an ad-hock plunge in shallower waters during the summer months, but the investment in the drysuit changed the way I dive forever.
Author: Arek Cetes - DMC