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Dry Suit

One of many uses of a Dry Suit

Dry Suits! You have to have one right? Well here is a bit about mine. Including some history you likely don't care about.

So why a Dry Suit? Well I live in the middle of the country and even in the summer a dive to 80' or so is still at least cold. It is certainly not required to have a Dry Suit to dive around here. I dove around here for two years in a 7mm Wet Suit with a 5mm hooded vest over that. Don't forget thick gloves and booties. In fact just a short while ago (Aug 2009) I have dove to 114' at 45 degrees In Mermet Springs IL, it sounds very cold and it is but you have to remember that you are only down there for about 10 minuets before you start your ascent and the water gets warmer at the surface. so the time of exposure is very short and you can overcome it very quickly.

However I have a warning for you about diving in the winter. the closest to getting in trouble with the cold that I have ever come was in 2007 the day after thanks giving when I dove Table Rock Lake with two friends (they where in dry suits and I didn't own one at the time.)  The water temperature was 55 degrees at the surface and at 80' very cold, the air temperature was around 35 degrees I believe. We went out on almost an hour dive which I was ok on, but when I came out of the water I mistakenly took down the top of my wetsuit very quickly. As opposed to leaving it on for a while to rebuild my core body temp. A little wind, 35 degrees, wet, and having lost a lot of core temperature on the hour long dive and that was just about it. My poor friends had to help carry my gear back to the vehicle etc. not good. The difference between this dive and the one just a couple of weeks ago in Mermet Springs is that as we ascended the water warmed and the air temperature was seventy to eighty or so. One of the very big advantages of a dry suit is after the dive, where you just unzip it and you are dry and warm. it works very, very well. 

Learning about Dry Suit's

So a Dry Suit was defiantly in my future. But what, where, which etc... There are a lot of options when it comes to Dry Suits and having no first hand experience with them I went around to find as much information on the net and other resources that I could. But that was basically poor information. any rate... So on to another option, enter DUI Dog Days (www.dui-online.com). This is an event that is held roughly monthly or so by DUI all around the country during the summer. What you can do is go to one of these and for a small fee (about $10) you get to try their Dry Suits. This is kinda fun, and I found that many people likely will never buy a suit but they go to them for a fun weekend. And they are ok as that goes. In case you are wondering you do not need to be Dry-Suit Certified to do this but then they will ask that you dive with one of there volunteer support divers. Which is a little lame but I can understand there position I suppose.

I went to one of these and found some things out. the first thing was that my body type is not so easy for most Standard Dry Suit's to fit. I am 6'2" and thin, about 180lbs depending on the day. So when I get a suit tall enough to fit me without making me squeak painfully when I raise my hands above my head it is wide enough to fit another person in there with me. Typically 40" or more waste where I have a 32" waste. This may not bother some people to have all of that extra materiel to wallow around in but to me it was very annoying. Then again I like a BC that fits snugly and moves with me as opposed to moving around me.  Some people are very comfortable with there gear sort of floating around them, hanging off of them but that is just not my preference. To those people the standard fittings (by the way that observation is generally true for most manufactures I checked while looking at various Dry Suit options not just DUI Sizing) might be just fine but I quickly decided to get a custom fitted suit (in no small part by the deal my local Dive Shop helped me get, www.goscubaadventure.com).

Dry Suit types

There are several types of materiel and technologies in the materiel used to make a dry suit. Most companies have there own term for many of them. As for me I tend to put suits into three big categories. Neoprene, Laminate, and Rubber. Of course under each of these there are many manufactures variants. Of Neoprene there are regular neoprene, crushed neoprene, compressed neoprene, yadda, yadda, yadda. in Laminates there are several as well, tri-laminate, bi-laminate this and that. Of rubber there are a couple of companies that make a full rubber suit. I am not sure if they are still in production or it is just old ones I have seen. Most dry suits that I have come across out there are either some kind of neoprene or laminate. Neoprene are said to be a bit more durable with
regard to abrasion and puncture but are less flexible and a bit heaver. while laminates are possibly a bit more puncture prone but light weight and very flexible. Just don't think that a laminate will puncture or rip quickly just because it is not a neoprene. The laminate suit I have is very durable and it would take a significant effort to put a hole in it. At the same time some neoprene suits have been "crushed" or "compressed" which permanently makes them thinner and more flexible while maintaining the same amount of material connections in the suit. keeping in mind that neoprene suits will stretch slightly as you move where laminates tend not to stretch at all. I chose a laminate as I have said for a couple of reasons.
  • the slick surface is hard to catch or snag on things.
  • less expensive.
  • lighter weight, and more flexible (read more comfortable.)
  • easier temporary field repair.
On the field repair issue. It was pointed out to me that a puncture in the suit (providing it is small enough) can be temporarily fixed by drying the damaged area and applying duct tape on both sides. I am not sure if you could do this with other materials or not but posibly.

My suit is a Signature Series TLS-350 which is a custom suit. I had the overlay panels put on in another color (as it didn't cost any more) and that way it was a little more identifiable than just the typical black dry suit. I really didn't care what color so long as it was bright. To help with visibility and identification in low light and low visibility diving. I will say though when I ordered it with Red on it I got a lot of ribbing from the local divers and a lady at DUI called the Dealer back just to "make sure" that I had thought it through, But when it came in they all said that they liked it.

How a Dry Suit Works

Since I haven't mentioned it and in case you are not familiar with what makes a Dry Suit a Dry Suit I thought I should point it out, put simply stretchy and tight, latex seals and a water proof zipper.

More specifically around the neck opening, and usually the wrist openings and sometimes the ankle openings there is an almost cone like seal usually made of latex but some older ones are made of neoprene. These seals will stretch quite a bit and they are cut to fit you specifically with just a pair of scissors (you do this not the manufacture). Once on they should have a section (somewhere around an inch is great) that lays flat against your skin. Obviously it is a tight fit or it wouldn't work. The seals must be much tighter than your wetsuit but it should not suffocate you or cause direct pain. Some suits have these seals on the ankles but most have built in booties in the suit. This typically leaves three openings, one for each wrist and one for the neck. Sometimes these seals will rip and or tear and have to be replaced.

In addition to the seals there has to be a waterproof zipper. Unlike your wetsuit this zipper does not come up to the neck opening in any way. Common placements for the waterproof zipper are across the shoulders horizontally, about from mid triceps to mid triceps, Sometimes called a traditional or more likely 'shoulder entry'. Or over one shoulder (say the left for arguments sake) and across the front and around the waste. The first one across the shoulders is the more traditional and in some respects the wisest. Mainly because this results in a zipper that is much shorter and not exposed to as much flexing and bending when on the dive. The second version is easier for the diver to get in and out as they can zip it them selves an as such it is called a 'self dawn' model. The down side of the self dawn model is that the zipper is much longer, has more turns and flexes in the water, and you also need to have some sort of articulated section in your suit to allow you to get your head and arms up and into the suit. Usually this section will expand out six to eight inches and once the suit is on their is a strap or plastic clip to keep it in place and more streamlined. With the traditional (horizontal zipper) you just soft of drop into the suit from the top and back. So they can be more closely fit, without the requirement for more material and complex stitching of the self dawn suit.

Comments on features and accessories

If possible get dry gloves of some kind. some people are not into this but dive a couple of suits if possible and decide for your self. I have dry gloves and love them. when I dive with my hands wet it may be in my head but I am much colder than if I dive with my dry gloves. it is a worthy addition. One thing to think about though is that you hand will be in air. this is what keeps you warm but also it makes getting a hold of small things a bit more difficult. many gloves are made of molded rubber of some kind which are not bad to use. typically an under glove is used for insulation, nit or fleece of some kind. I have the first version of neoprene zip-gloves offered by DUI, they are more durable by far than the formed rubber kind and they have some small inherent insulation (I usually where them without the fleece under gloves just to improve grip and feel.)  But they have no real grip pads on the fingers or palms so getting a hold on small slick things can be very challenging at times, it also severely reduces your tactile sensations. (knowing what you have your hand on when you can't see your hand.)  DUI came out just a year later and fixed this with some grip stuff on the palms that helps a lot I have heard but that doesn't help me. I plan to use some Aqua Seal to drizzle some grip around the palm. I will let you know how that works.

DUI offers a zip-seal deal which lets you switch out from the gloves to a set of wrist seals on the fly, I really like this and some other manufactures have similar systems. I have only used the zip-seals from DUI and they work well in my opinion. You do need to check them before each dive and not get careless about this. If they are not fully sealed up then they could come off in the water, and that dose happen I had my left glove come off on a winter dive. but I can't blame the seals I know I was neglectful about checking them. All and all not a horrible experience.

Neck seals should be user replaceable, mind you that is just my opinion. Some makes and models of dry suits have to be shipped back to the factory to have the seal replaced. Stuff that! some also offer swappable neck seals like the wrist seals. DUI has a zip-seals for the neck, it works a little different than there wrist version which makes it much more secure but is easily replaced. The one down side to any of these neck seal quick replace systems is that they end up with some kind of a hard ring (or semi-hard) around your neck which if you are skinny and bony like me can have a habit of digging into your neck a bit. just something to be aware of.

Pockets, um, this is simple, yes, one on each thigh. I have poky out zipper pockets and they are ok, If I had it to do again I would get the flap open style bellows pockets. believe it or not drag in the water counts for a lot of effort. Plus, flaps with Velcro closures are easier to work than zippers when you have big gloves on (that are full of air.)

integrated boots or integrated socks and separate boots. I have a clear preference for the integrated socks on the feet and separate boots. but I couldn't really tell you why.


I haven't pointed out yet that dry suits need you to where something to keep you warm under them. even the thick neoprene ones need you to where something. The point is that you need something to keep the inner surface of the suit away from you that can be full of air so you stay warm. The concept works just the same way as the insulation in your house. some fiber to give it loft while allowing airspace to be filled by air. and the less this air can move around the better. Consequentially some fibers are better than others. Fleece (properly called Polar Fleece) of some kind is very common, some more expensive options are Thinsulate (a material from 3m), Down wouldn't work as it is to squishy. As a matter a fact when Thinsulate is used it is often type B thinsulate. There are two types, A and B the B type is intended for things like shoos and boots where it will be subject to significant compression while Type A is geared toward low or no compression situations such as a jacket. A dense Wool I would also think would work well so long as you didn't have a leak. Sometimes just a good pair of sweats will work fine. That being said sometimes it is warm enough that I have just wore my regular shirt and pants under my dry suit.

I have both Fleece and Thinsulate dry suit undergarments. It is hard to say which I prefer.
  • Thinsulate (DUI Ultra 400 Insulation)
The thinsulate one that I have is from DUI and I got it the same time I got my dry suit. It is the ultra 400 version. the 400 refers to it's weight(400 grams per meter squared) This is a lot of insulation in one garment. To give you a comparison if you go looking around for arctic mountain climbing coats about the heaviest you will find is 200 weight (again 200 grams per meter squared). Be sure not to confuse the weight of the garment with any kind of "R value" Different kinds of materials will have different insulateive properties given the same weight. So, at any rate this is a lot of insulation, as it is made of the type B variant it is very dense and feels like thick or dense wool. it is no doubt the warmest that I own, you can't where it in the house for more than a bout 15 minuets before you will be sweating. I do have a problem with this undergarment that is more related to the fit. For one thing the dry suit is custom sized and the undergarment is not, so it is like wearing a large suit under a smaller suit. the next problem is with the space allowance of the custom sized dry suit. While my custom sized dry suit fits very well and comfortably with thinner insulation it is a bit tight with this thicker insulation on. I did not try and send it back to DUI, they may have been able to adjust that but it was very close to begin with and in my opinion since the insulation was not custom sized but the dry suit was there was going to be no way to fix this issue. the only way to make it better would be to size the dry suit to match the insulation which would effectively be not sizing it to fit me.
  • Fleece (Polar Fleece, Generic)
The Fleece garment that I have is a generic one that I got for cheep off of eBay. It is new, there is a guy selling them claiming that they are made for some dry suit manufactures generically then branded later. These are supposedly the unbranded version of the same thing. What ever. it is made of double layers of 250 weight (again 250 gram per meter squared) Polartec Power stretch fleece and is a simple jumpsuit design. It works all in all ok, and was worth the price. Having the double layers is a bit annoying and slightly defeating the purpose of the wicking action of the material. Whering this insulation it is much easier to get into and out of my dry suit but it is less insulation than the thicker thinsulate suit meaning that I am colder.