Scuba diving in a Dry Suit - A beginners guide

How to use a dry suit for first timers.

Dear diver,
now that you´re considering diving in the land of Ice you are probably aware of the need for proper exposure protection.
A wise man once said “It´s better to be dry and warm than cold and wet”, and we wholly agree.
Learn dry suit diving Dive Iceland
Learn dry suit diving © Dive Iceland, Tobias Klose
Our aim is not merely to show you around some of Iceland´s – indeed the world´s – most amazing dive sites, but to do so both safely and comfortably.
Therefore we invite you to take advantage of this beginner´s guide to dry suit diving.

1. Formal education

You can obtain a PADI dry suit speciality certification by doing the PADI dry suit specialty course, which combines a self study with the PADI dry suit manual, a theory session in which your instructor will go over the knowledge reviews of the dry suit manual with you, a confined water session and two dives in open water in which you will do the practical skills.
To dive Silfra with us, you don‘t necessarily need to have prior dry suit experience but it helps to enjoy this fantastic dive site, since you are not occupied with learning how to dry suit dive.
You can either just do the regular Silfra Day Tour and get a dry suit briefing from our dive guide and then try it out or you can combine the tour with a PADI Dry Suit Specialty Course in order to obtain a certification card which is required in some other places and dive sites.
For further informtion about the PADI Dry Suit Specialty Course, please have a look at this website: Dry Suit Diving Course in Iceland with DIVE.IS

2. What to wear underneath the dry suit (layering)

Layering is important, it is the base layer that goes under you dry suit undergarment and dry suit and it depends on the water temparature and what kind of dry suit you use.
Neoprene dry suits need less layering than e.g. trilaminate dry suits.
The colder the water the more layers you add and this means that for every layer that you add, you need to compensate for with additional weight.
Your first layer should consist of thin woolen underwear and a pair of thick woolen socks. Fleece or other syntethic materials are fine as well but cotton is not recommended as it doesn‘t insulate as well, especially if it gets damp (e.g. sweat).
In Silfra we dive with neoprene dry suits and provide a thick and very good undergarment. The water is 2-3°C but still you need just the provided undergarment and thick socks (please bring those) in order to keep warm.

3. Dry suit components

Dry suits have 5 major components which need to be well maintained and taken care off to have an enjoyable dive.

Dry suit wrist seals made of latex
Dry suit wrist seals made of latex © Dive Iceland, David "Alfi" Ramsay
a. The dry suit wrist seals
The wrist seals of a dry suit are made of latex or neoprene (our dry suits have latex wrist seals). These seals need to fit tightly arround your wrist to stop any water from coming in, they need to be handeled with great care, because they can tear easily, especialy if you have long finger nails. Please work with caution when you put your arms through the sleeve and take them out.
It‘s best if our guides assist you with doing this to prevent you from missing a dive because of a ripped wrist seal.

Dry suit neck seals made of neoprene
    Dry suit neck seal made of neoprene © Dive Iceland, David "Alfi" Ramsay
b. The neck seal of the dry suit
The neck seals of dry suits are made of latex or neoprene as well (our dry suits have neoprene neck seals). These seals need to fit tight around your neck to keep water out and air in. However, it may not be too tight because it could slow down or block blood flow.
But don‘t panic :-). It might take a moment to get used to the neck seal if its your first time. Neoprene neck seals get folded in towards the neck to create an airlock which helps to keep water out and air in. Also, if you have long hair, it‘s important to get all your hair out from underneath the seal.
Please ask our guides to check if you have done it right or better ask them to assist you with folding the seal to the inside.

c. The dry suit zipper
Dry suit zippers in front and on the back of the dry suit
Dry suit zippers at back or front of dry suits © Dive Iceland, David "Alfi" Ramsay
This is where you get into the dry suit, zippers can be in the front across your chest or on your back from shoulder to shoulder (our dry suits have the rdy suit zipper in the back).
The dry suit zipper is very fragile and it needs to be waxed often to keep it moving smoothly, please do not step on the zipper while putting your dry suit on. Our suits have a protector flap that needs to be pulled down to make sure the zipper does not get stuck in the material of your base layers when closing it. Once it‘s closed, give it a good tuck to make sure it is fully closed. Closing and opening your dry suit zipper always requires a second person (your buddy or guide) because it‘s pretty much impossible to close alone and it can get dammaged by trying to do so.
The best way to close it is with a slow and smooth pull from one side to the other instead of giving it multiple tucks.
Please ask our guides to assist you if you are unsure of how it is done.

d. The air inlet and air outlet valves of the dry suit
Dry suit outlet and inlet valves
Dry suit air outlet and air inlet valves © Dive Iceland, David "Alfi" Ramsay
The dry suit valves are used to let the air in and out of the dry suit. It works basically the same as with a BCD. The inlet valve is located on your chest and has to be attached to a low pressure hose coming from the 1st stage of your regulator. The valve has a button in the middle that needs to be pressed down to push air into the dry suit.
The outlet valve is located on your sholder. Outlet valves can be set to let air out of your suit automaticaly or can be set that you have to let air out you self by pressing on the valve. For first time drysuit divers it is better to keep it closed so you can better control the flow out of your dry suit. To have the valve on the manual setting you turn it clockwise as far as you can. To have it open for automatic release you turn it the other way around.
Please ask our guides for assistance if you are unsure.
Dry Suit inlet and outlet valves These five elements need to be checked before every dive and needs to become a standard buddy checking proccedure.

4. Drysuits versus Wetsuits

There are some key differances between diving in a dry suit and using a wet suit. Dry suits are used for cold water diving while wet suits are used in warmer waters:

a. In a dry suit you don‘t get wet on your body so the air in your suit acts as insulation. In the wetsuit water seaps into your wet suit and acts as insulation once you body warms it up. Dry suits keep you warmer because in water you body loses temprature 25% faster than in air so being in a wetsuit surrounded by water you loose body heat faster than being surrounded by air in your drysuit.

b. When diving in a dry suit you control your buoyancy with your dry suit instead of using your BCD like you would with a wet suit.

c. With a dry suit you need a lot more weight than with a wet suit. The reason is that you have a large space of air that surounds your body and all of this air needs to be pressed under water. That is done by adding more (led) weights.

d. Your regulator has two low pressure hoses, one goes to the BCD and the other into your dry suit inlet valve.

5. Why use the drysuit for boyancy

The reasons we use the drysuit to control our buoyancy and not the BDC is that the air inside the drysuit keeps us warm, so if most of the air is in our BCD it does not help us to stay warm. Another reason is that when you dive down a few meters the air inside the drysuit compresses which creates a squeeze on your body. To compensate for the compressing air we need to add air to our drysuit. Tthe deeper we go the more air we need to add.
On the other hand, when you come back up to shallower parts of your dive, you need to release some of the air in your suit because it expands again due to less surrounding pressure of the water.
However, of course it is also possible to use your BCD for buoyancy control in a dry suit, so if you experience difficulty to use the drysuit: The BCD is always there, too.
On the other hand you might not want to end up using both drysuit and BCD at the same time since this can create confusion on where to release air when you come back up.

6. Drysuit hazards and tips

When using a drysuit keep in mind that there is an air space and it surrounds your whole body. In order to press you down underwater you need to use quite a bit more weights to compensate for the extra air than in a regular wet suit.
So instead of using short bursts when putting air into your BCD when diving in a wetsuit you now have to hold the air inlet button of your drysuit in for a longer time to feel an effect. Also because its a bigger air space your lugs don‘t play such a big role in going up and down in the water.
A very important thing to remember is that you need to always have the air outlet valve of your drysuit at the highest point of your body when you want to release air. Just like with a BCD you have to lift the inflater/deflater hose up to get the air out so also with the drysuit, make sure your feet are lower than the outlet valve on your shoulder.
The classic (but very rare) dry suit diving hazard is that divers have their upper body lower than their legs and at some point the air gets into your feet and turns you upside down. This can make it impossible to release air from your drysuit and you could end up doing a rapid accent.
This can be corrected by kicking hard with your feet to get them below the valve again.
On your first drysuit dive we will not dive deeper than 10 meters, to make sure that in the rare and unlikely case this would happen you are still well within safe limits.
Drysuit diving opens up a big range of new and exciting dive sites different to the mainstream dive sites in the warmer climates. It‘s a great amazing new world that‘s waiting to be discovered.
The only way to be succesful in diving with a drysuit is to try it out and practice.
Don‘t feel overwhelmed by all the information. Take in what you can, your guide will go through this with you again once you stand by the water.

7. Books and links to websites on drysuit use

Dry Suit Diving Course in Iceland with DIVE.IS
Wikipedia about dry suit diving
ehow about dry suit diving
Skin Diver about dry suit diving
PADI dry suit diver course
Dive Iceland with DIVE.IS, the perfect opportunity to learn dry suit diving

If you have any comments or questions, please contact us at
We look forward to diving with you.
Your DIVE.IS team