FOR DIVERS IN TEMPERATE AND COLD WATER, breaking through the thermal barrier has been essential to progressing towards repetitive, longer and deeper dives. Once you get cold, you become distracted mentally, which affects judgment, and your dexterity also declines, making simple manual tasks difficult.
Humans lose heat to the water so fast that for demanding – or even comfortable – dives in many conditions a wetsuit just can’t cut it. It’s then that we must turn to drysuits.
Drysuits, like wetsuits, are passive – they don’t generate heat to keep you warm. But by enclosing your body in a pocket of air, they can slow heat-loss considerably, compared to a wetsuit in which your body is in direct contact with water.
Air is a good insulator, so the undersuits often used with drysuits for greater warmth use materials that also trap air.
Some drysuits are made from expanded neoprene, like wetsuits. The neoprene provides insulation and buoyancy but, like a wetsuit, will crush under pressure, so buoyancy and insulation diminish as you descend.
Membrane drysuits use materials such as trilaminate, a thin fabric of nylon and rubber. These keep you dry but offer no inherent insulation from the cold in themselves, and are usually near neutrally buoyant.
In the middle ground is compressed neoprene., which is expanded neoprene that has been reduced in thickness by largely collapsing the rubber’s bubble structure.
This should result in a drysuit that is rugged, provides some insulation and undergoes little buoyancy shift with changes in depth.
Scubapro’s Exodry 4 compressed-neoprene drysuit is not an expensive suit, but it certainly impressed me. It’s a back-entry suit and comes with latex neck- and wrist-seals and attached boots.
The neoprene itself is 4mm thick and is nylon-lined on both sides and, of course, the seams are dry-stitched.
A chest-mounted inflator and bicep-mounted adjustable auto-dump are included, along with a hose, maintenance kit, bag/changing-mat and wetsuit hood.
Closing the zip before you dive and opening it afterwards requires a buddy, or at least an assistant. The zip has a generous underflap for insulation. Along the outside there’s a fold-down protective panel with Velcro tabs that keeps your BC from rubbing against the zip. Scubapro offers other self-donning front-entry drysuits for solo-divers or those who value their independence.
Zip aside, this is an easy suit to don. The boot uppers are neoprene, rather than heavy-duty wellie types, so you don’t have to dislocate your ankles to slide your feet in.
There are ankle-straps to minimise air migration and help keep your feet in the boots if you do mess up and go Polaris.
Wrist keeper detail.
Adjustable braces with quick releases are fitted, helping to keep the suit positioned properly, but these are especially useful at the surface when you want to roll down the top and loop the sleeves through the suspenders.
I spent a lot of time wearing the Exodry 4 on the surface for selfies, and found it as comfortable as any other compressed neoprene drysuit I’ve used. The neck features a warm-neck collar, adjusted for size and comfort with two more Velcro tabs. Its purpose is to keep the bib of your hood secure inside the collar so that cold water doesn’t hit your neck.
A drain-hole with a real grommet, which is a nice touch, allows trapped water to exit the collar as you break surface.
This prevents water falling inside the suit when you take off the neck-seal.
Scubapro has fitted the Exodry 4 with reinforced shins for durability and flex-panels behind the knees to make finning, walking and climbing ladders more comfortable. There’s additional reinforcing on the front shoulders where BC straps and buckles can cause chafing, as well as on the seat, an area prone to scuffing-up.