The primary reason why you need an exposure suit is you lose heat to water about 20 times faster than to air thus a temperature of 27°c may feel fine on land but will feel cold in water after 30 minutes of diving. What happens is that the body heats up a thin layer of water surrounding it. That water then expands and moves up, to be replaced by cold water, that cycles continues until you feel cold. The underlying reason is that our average body temperature is just under 37°c, if the water is any cooler than that, heat loss occurs, and it happens faster the greater the temperature differential between body and water temperature.
Let’s take a look at the different exposure suits that are readily available for use in tropical waters. We have vests, shorties, rash-guards, exposure jackets and wet-suits. Within these five categories there is already many sub-categories, this post is aimed to enlighten you on what is available and pros and cons of each of them.
First we have the exposure vests. Vests comes mainly in 2 designs, a hooded vest and a non-hooded vest. An example of a non-hooded vest would be the Bare vest.
Most vests are made of neoprene material, and comes in assorted thickness fro 0.5mm to 5mm. Vests can be used on its own or layered with other exposure suits to help keep you warm. The vests are normally lined with a metallic material which helps to keep your core warm. The choice of having it hooded also adds a plus point as for some who gets cold easily, they can retain heat longer wearing the hood like the Scubapro hooded vests.
Only disadvantage of wearing a vest is that some which does not have any Velcro flaps could be a hassle getting in and out of due to the metallic material that tends to stick to your skin. Overall it is a good addition as it gives you options to layer it with other suits or to wear it on its own.
For those who do not get cold easily and want an exposure suit which does not affect buoyancy as well as protect you from uv-exposure the the rash-guard is your new best friend. Rash-guards come in all sorts of materials and thickness. The most basic one will be better known to be a dive skin. It is the lightest of
exposure suits and offer the least amount of protection and are only about half a millimeter thick.
Some consist of Lycra, a trademarked DuPont product that is sort of a nylon/spandex fabric, sometimes with cloth on one side. A Lycra dive skin will look something like this Aropec.
If you are looking for something to keep you warm and is easy to get in and out of, than you would go for a thermal rashguard. These rash-guards are made of fleece thus keeping you warm as well as give you more mobility and comfort. Plus points is that it does not affect your buoyancy either, so no additional weights needed to compensate. These rashguards comes in many assorted designs, colours, short-sleeved, long-sleeved as well as fit for men and women. The Gul Viper and Gul Evotherm are examples of these.
Some of these rash guards comes in a different material as well. The Gul Profile Thermo Top is made of neoprene material and comes in different thickness, from 0.5mm to 3mm making it suitable for different water conditions. The mechanics of it is similar to other wetsuits as well, it traps a thin layer of water between your skin and the suit thus allowing you to heat up the water and retaining it’s heat. Downside is this will affect your buoyancy by a bit so make sure you compensate for it.
There is a brand however who have manufactured similar tops but with state of the art materials which helps achieve a neutrally buoyant exposure suit. It’s the Fourth Element Thermocline range.
Still too much effort trying to pull it over your head? Here’s a solution for those a slightly lazy but still want to be warm and at the same time look good, we have the jacket-style rashguards! It’s made of neoprene and comes in different thickness similar to the profile tops mentioned before, assuring you it will keep you warm in different waters. Best part is you can even layer it on with a thermo guard for added warmth. Available in many chic designs and colours like the Gull SCS Outer Suit.
Finally we have come to the most common of exposure suits, the shorty and full wetsuits. These suits are mainly made of neoprene material but how they are stitched is different. Three main stitches are utilized within wetsuit development. As you may figure, stitching involves making gaps in neoprene and passing a string through. These openings can let water in even with waterproof neoprene, so the sort of sewing is essential when recognizing how warm a wetsuit will be.
This system is the least complex method for stitching, and the least viable at keeping water out. You would not see this in high-end wetsuits. The two edges of the material used are pinched together and afterward sewed to hold them together. This technique definitely decreases the adaptability of the crease. It additionally leaves a lump within the wetsuit which might cause chafing.
Flatlock stitching includes laying one edge over the other, then stitching over the neoprene. This results into a very flexible but strong seam.. The downside to a flatlocked seam is that the method used makes numerous holes thus making it more susceptible to water leaking in. This makes it more suited for wetsuits tropical waters.
The edges of the neoprene are put end to end and glued together. They are then stitched in the inner layer, however the stitching does not go through to the outside of the neoprene. Resulting in watertight, flexible seams. This is perfect for for icy water temperatures, and is can be seen in the ‘higher-end’ wetsuits thus making it that much more expensive.
Double blind stitching might be utilized on thicker wetsuits, where the seam is blindstitched on one side, the again on the converse side.
Now that you know how each suit is made and the benefits of each of them, you can look into what suits your diving. If you’re looking for a shorty that protects you from the sun as well as keeps you warm in tropical waters then a good choice would be the Mares 2nd Skin Shorty. It is a 1.5mm shorty with sleeves to protect you from the sun and added feature is it is made with a front zipper thus making donning it that much easier.
Do not like shorties because it gives you weird tan lines? Then why not invest abit more to get a full wetsuit like the Gul Response steamer. It comes in 3mm thickness, flat-locked stitching and it has different designs to help differentiate you from other divers. Better yet they have designs for ladies too.
If you are into black and want to look really professional then the Scubapro Thermal Tec is for you. This wetsuit comes in different thickness from 3mm to 7mm and it is in built with zippers on the wrists and ankles making donning much easier. It has an added fleece material layered on the inside of the suit ensuring your warmth in any dive.
There are many more exposure suits in the world right now with many new technologies to help keep you warm and comfortable in the water and each tailored for a specific type of diving. So which suit excites you?