Why would a decent wetsuit make a difference?

The last thing you want to do is catch a cold. Without the right exposure protection, you can ruin a dive. When you're cold underwater, you can't concentrate on anything but shivering. All you can think about is counting down the minutes until you get out. In extreme cases, you put yourself at risk of hypothermia.

Always plan to be as warm as possible. Even if we dive in very warm water, we can still get cold if we stay in the water long enough. If we think back to our diving theory, the water cools us 20 times faster than the air. We can sit happily in the sun all day at 28°C. But after a day of diving in warm water at the same temperature, we will start to feel the cold.

If your dive closet is really smart, then you will be able to choose a set that will keep you warm at any temperature. You can mix and match combinations of suits, gloves, hoods, fin socks, shields and baselayers that suit the conditions.

 

How does your wetsuit keep you warm?

Wetsuits and semi-dry suits are permeable. In other words, they allow a thin layer of water to pass through and hold it between our bodies and the suit. Our skin heats this water, so the heat is dissipated more slowly.

The very small inflatable cells in the wetsuit material provide us with enough insulation to keep this film of water warm. The thickness of the wetsuit depends on them. However, we must remember that this insulation is affected by the water pressure, which decreases as we descend, and is less effective. The micro bubbles in the neoprene are compressed by the water pressure, and the deeper we go, the more pressure is put on them. The thicker the wetsuit, the more it will be affected by this phenomenon.

In contrast, drysuits are waterproof and keep the diver isolated from the water. They can be made of neoprene or tri-laminate. These materials do not really provide heat on their own, but divers can wear a thermal suit under a drysuit.