Of all the pieces of dive gear you own, your wetsuit might be the most personal. That stretchy, rubbery shell is essential in all but the warmest conditions, and even then they protect skin from abrasion. For optimum thermal protection, it should fit like a second skin.

The Basics

Customized wetsuits exist for a variety of water sports, but dive-specific suits are in a league of their own. Compare a diving suit to those worn by surfers and you’ll see functional differences. The arms and shoulders are positioned differently (surf suits require better overhead reach for paddling), and diving wetsuits are often thicker to account for the compression that occurs at depth, which reduces insulation.

Wetsuits are traditionally made with closed-cell foam neoprene, a material that starts as a rubbery, white chip with a consistency like the sole of a sneaker. Plasticizing and foaming agents are used to soften the material, which is then vulcanized so it maintains its shape. Carbon black is added to improve tensile strength and turn the milky-white neoprene black, which makes it more resistant to sunlight.

There’s a lot of science behind modern wetsuits, and the materials used can significantly affect the manufacturing cost. “When you buy a wetsuit, the price is related to its contents,” said Allan Edmund, president of Henderson Aquatics. “Neoprene is a relatively expensive ingredient. Wetsuits made from pure neoprene maintain their flexibility longer. They’re easier to put on, and they tend to be more expensive than wetsuits made from combinations of neoprene and other materials.”

The type and quality of fabric placed over the neoprene affects price, too. Wetsuits made with higher-stretch fabrics such as Lycra® and spandex are more expensive than suits with nylon exteriors. Although it’s difficult to generalize, less-expensive suits often have a lower percentage of neoprene. Such suits may wear down more quickly, becoming stiff and hard to put on.

Keeping Warm

Right hand and wrist of a person wearing a wetsuit

Neoprene density, fabric thickness and the wetsuit’s sealing properties are the elements of suit design that most influence warmth. “There’s an industry standard that for Caribbean destinations, diving in a ‘three-mil’ is acceptable,” Edmund said. But, of course, everyone has his or her own level of cold tolerance. Generally, the colder the water, the thicker the wetsuit or the more layers (e.g., hooded vests or shorties worn over full suits) you’ll need.

It’s a common misconception that wetsuits keep you warm by allowing your body to heat the layer of water between the neoprene and your skin. If the water is 70 degrees at the surface, and your body has to warm a layer of water at that temperature, it’s not energy efficient — you have lost too much heat from the outset.

A wetsuit’s ability to keep you warm has more to do with limiting water circulation. In general, the more tightly the suit fits, the less circulation you’ll get; the theoretically ideal wetsuit would have no water flushing through.

Thus, wetsuits should fit snugly. For beginner divers who may not fully understand wetsuit efficiency and may not be accustomed to the sensation of pressure on their chests, the tendency can be to select a wetsuit that fits too loosely and allows too much water flow. But poor fit compromises the potential warmth of even the best suit.

The desire to minimize water flow through the wetsuit has led manufacturers to focus on more efficient sealing of the wrists, ankles and upper chest area to reduce water flushing. Many brands use features such as double cuffs or skin-in seals to reduce water entry and thereby improve insulation.

Function and Fashion

Two divers jump off platform and into water

While wetsuits were originally designed solely for thermal protection, today they’re fashion pieces as well. The earliest suits were like Model Ts: You could have any color you wanted as long as it was black. With the introduction of colors and design elements, and with women’s wetsuits in particular becoming very fashion forward, wetsuits are now specialized clothing for the marine environment.

In addition to protecting your body from the cold, wetsuits have other advantages. The layer of neoprene serves as a comfortable buffer against heavy gear and tight straps. While divers should always strive for neutral buoyancy and no reef contact, wetsuits offer some protection against accidental run-ins with stinging marine life and sharp objects on wrecks.

Most wetsuits have back zippers, but some continue to be made with zippers in the front. “Front zips provide a seamless surface for the weight of the tank on the back,” said Alexandra Schweickhardt of Camaro. While front zips were not popular in the past due to the pressure they sometimes put on divers’ throats and necks, Schweickhardt said the rise of asymmetric zippers and water flaps has made them more comfortable.


The better you care for your wetsuit, the longer you can expect it to last; exposure to UV radiation and salt water can cause suits to become brittle over time. “After use, rinse your wetsuit with fresh water, turn it inside out, and hang it on a large hanger in a place that’s cool, dry and out of the sun,” Schweickhardt said. Repeated exposure to the pressure at depth can also decrease the thickness and warmth of wetsuits. A wetsuit should be seen as a depreciable commodity; if it doesn’t keep you as warm as it used to, it may be time to upgrade.


While some might dream of wetsuits that can be sprayed on with the ease of aerosol sunscreen, that’s not likely any time soon. New trends include materials designed to provide the thermal protection of neoprene without the depth-related buoyancy considerations. Wetsuit manufacturers today are focused on improving the ease of getting into and out of suits as well as improving warmth. Zipperless designs are being explored for the surf market, but in diving the focus remains on easy donning and removal. Divers who might be a bit older or are carrying a little extra weight could find it difficult to get through the neck opening of a zipperless suit. Instead, waterproof zippers are used to gain a similar efficiency to zipperless suits with greater ease of donning. Look for a continued focus on improving wrist, ankle and neck seals as wetsuits continue to evolve as fashionable and virtually indispensible marine garments.

© Alert Diver — Q4 Fall 2012