Poseidon Adventures Blog

Thermal Protection

Thermal Protection

by Randy Piper

How To Choose A Wet Suit

The two reasons that divers use an exposure suit of some kind is to prevent heat loss and to protect their skin from cuts and abrasions. There are three kinds of exposure suits on the market: body suits, wet suits, and dry suits. It is the wet suit, however, that is the topic of interest for this examination.

Water conducts heat away from the body 25% faster than air at an equal temperature. Thus, even though the water temperature is WARM, with prolonged exposure, the body's core temperature will drop and cause the diver to become fatigued. In extreme cases, water temperature below 75 degrees F can cause hypothermia and loss of life. The other reason for the use of wetsuits is for protection of abrasions and stinging from animals. People do not have the same agility underwater that they have on land and thus we need an added layer of protection.

Wet suits essentially work in two ways: they insulate and retard water circulation. Most are constructed of neoprene foam as it is an excellent material for insulation purposes. The neoprene functions to retard heat loss though radiation. Thus, as a diver goes deeper the gas in the neoprene compresses and the insulation quality becomes less. The other way a wet suit works is by allowing a thin layer of water in next to the diver's skin where the body works to warm this thin layer in a process known as thermal equilibrium. As the water stays at rest against the body, there is very little energy expended to stay warm, but if water free flows through the suit then the body will have a much more difficult time staying warm. Thus, it is important to make sure that the wet suit fits snugly against the diver's body. The only real drawback to these neoprene wet suits would be the need for extra weight when diving.

Wet suits are offered in several levels of thickness ranging from a thin .5mm suit to as thick as a 7mm suit. The thicker the suit, the warmer it will keep you as a diver so it is important to consider the destination and time of year when choosing your wet suit.

Wet suits also come in a variety of styles. The full suit type ranges between the step in shorty and the farmer john or the beaver tail shorty with waist high pants. There are full jump suits and just the step-in shorty. For diving in Oklahoma, the most versatile suit is probably a 3mm step in shorty with a farmer john, or a Scubapro back zip, nylon one jump suit. This is the only technology that works for layering, as the smooth nylon one won't bead up or allow water to remain between it's layers, like nylon two will. In the colder months, a diver would need the entire suit as well as for deep diving. After you take into consideration the type of diving that you will be doing, then you may consider the colors and other extra options as a spine pad or knee pads. Before you go any further, come into Poseidon Adventures and try on one of our large variety of wet suits. We carry Seaquest, Body Glove, O'Neill, and Scuba Pro brands from sizes small to XXL in men's sizes and if we don't have the one you want, then we can order it from the manufacturer.