Scuba diving in a Dry Suit - A beginners guide

What you need to know before diving with a Dry Suit with us

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 and dry suit experience requirement

Since March 1st 2017, all of our diving tours in Iceland require a dry suit certification or recent experience in dry suit diving - a minimum of 2 logged dry suit dives within the last two years.

You can obtain a PADI Dry Suit Certification by doing the PADI Dry Suit Specialty Course, which combines the self study of the PADI Dry Suit Manual with a theory session during 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. A dry suit certification obtained from any other diving agency also meets the formal education requirement.

You can combine the PADI Dry Suit Specialty Course with diving Silfra by joining our Silfra and Dry Suit Diver Course Combo, which allows you to dive Silfra and get certified in one day. If you already have the dry suit certification or recent logged dry suit experience, you can join the regular Silfra Day Tour.

In the following sections of this guide we will introduce you to the world of dry suit diving and the equipment we use on our tours, so you’ll know better what to expect and how to prepare beforehand. For those of you who are already certified or have dry suit diving experience, this guide will serve as a handy review before your tour. If you’re taking the Dry Suit Specialty course with us, this guide will orient you to the topics you will learn about on the course.

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

Layering is important when we are diving with a dry suit. In general, there are three layers:

1) a thin base layer against your skin,
2) a warm and thick undergarment, and
3) the dry suit itself.

The colder the water, the more or thicker layers you add. For every layer that you add, you also need to add additional weight to compensate for the added buoyancy. Material of the dry suit matters too: dry suits made of neoprene insulate more than ones made of trilaminate material.

Your base layer should consist of thin thermal underwear and a pair of thick socks. Woolen base layers and socks are best. Fleece or other synthetic materials are fine as well. Cotton base layers are not recommended as they don’t insulate as well, especially if they get damp (for example from sweat).

We dive with warm neoprene dry suits and provide you with a thick undergarment. You just need to bring a thermal base layer and an extra pair of thick socks in order to keep warm

3. Dry suit components

Dry suits have 5 major components which need to be well-maintained and checked before every dive to ensure safe and enjoyable dry suit diving experience.

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, neoprene or silicone - our dry suits have latex wrist seals. These seals need to fit tightly around your wrist to stop any water from coming in; they need to be handled with great care, because they can tear easily, especially if you have long finger nails. Please work with caution when you put your arms through the sleeves when donning and removing the suit and follow the instructions given by your guide.
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 also made of latex, neoprene or silicone - our dry suits have neoprene neck seals. These seals need to fit tight around your neck to keep water out and air in. However, the seal should not be too tight because it may slow down or block blood flow. Don’t panic! ☺ It might take a moment to get used to the neck seal if it’s your first time in a dry suit.

Neoprene neck seals are folded in towards the neck to create an airlock which helps to keep water out and air in. If you have long hair, it’s also important to get all your hair out from underneath the seal.

If you have a slender neck, it might be necessary to tighten the neck seal with a collar so it goes not move or let water in when you move your head. Our guides will assist you with folding the seal to the inside, and with the collar if needed.

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
Dry suit zippers enable you to get inside the suit. They can be in the front across your chest or on your back from shoulder to shoulder - our dry suits have the zipper in the back. The dry suit zipper is very fragile and needs to be waxed often to keep it moving smoothly; please do not step on the zipper while donning or removing your dry suit and also avoid letting it touch the ground in any circumstance as sand or gravel can get between the teeth of the zipper and break it.
Our suits have a protector flap that needs to be pulled down to make sure the zipper does not get stuck in the undergarment material when closing it. Once it‘s closed, have your guide check that it is closed all the way if someone else closed your zipper.
Closing and opening your dry suit zipper always requires a second person (your buddy or guide) because it’s impossible to close alone and it can get damaged 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 tugs.
Please allow our guides to assist you in closing and opening the zipper.

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. The principle is essentially 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 left shoulder. Outlet valves can be set ‘open’ to let air out of your suit automatically (default setting in our suits) or they can be set ‘closed’ so that you have to let air out yourself by pressing on the valve. For first time dry suit divers it is better to keep it open so it’s easier to release air from the dry suit. To have the valve in the closed setting, you turn it clockwise as far as you can. To have it open for automatic release, you turn it counter-clockwise until it stops..

Please ask our guides for assistance if you are unsure.

4. Drysuits versus Wetsuits

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

a. In a dry suit the idea is not to get wet on your body so the air in your suit can act as insulation. In a wetsuit water seeps into your suit and acts as insulation once you body warms it up. Dry suits keep you warmer because the thermal conductivity of water is 24 times higher than air, so your body loses heat a lot faster when in contact with water in a wetsuit.

b. When diving in a dry suit, we recommend controlling your buoyancy with your BCD as you're used to doing with a wetsuit. However, the air in the dry suit also affects your buoyancy and you need to consider inflating and deflating the dry suit when descending and ascending.

c. With a dry suit you need more weight than with a wet suit. The reason is that you have an airspace surrounding your body and all of this air needs to be pulled under water. This is done by adding more weights.

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

5. Controlling buoyancy in a dry suit

When you dive with a dry suit for the first time, you use your BCD for buoyancy just like you've used to doing in a wetsuit. However, there are two important additional points to consider regarding the dry suit.

Your dry suit creates an additional air space around you, which will affect your buoyancy. As you descend the remaining air in your BCD and dry suit gets compressed by the surrounding water pressure. This means that after a slow start you will suddenly descend a lot faster than you are used to. While you ascend this process happens the other way around. The air in your BCD and dry suit will expand due to the decreasing surrounding pressure. This is the reason why a nice slow controlled ascent may turn easily into a fast ascent while diving in a dry suit. Don’t worry, this can easily be avoided by reacting immediately to slight buoyancy changes by adding or releasing air to or from your BCD. Take your time on your first few minutes of your dive to get used to your dry suit. We also recommend holding on to the inflator/deflator hose all the time during you first dry suit dive.

You may also consider inflating the dry suit a little bit to avoid suit squeeze and for additional warmth. Be aware that while ascending you always need to deflate excess air from your dry suit through the dry suit exhaust valve on your left arm.

6. Drysuit hazards and tips

A very important thing to remember is that you need to always have the air outlet valve of your dry suit at the highest point of your body when you want to release air. As you're lifting the inflator/deflator hose up to get air out of the BCD, you're lifting your left arm up at the same time, letting air out of the dry suit. When deflating the dry suit, make sure your feet are always 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 dry suit and you could end up in a rapid ascent. This can be corrected by arching your back and kicking hard to get your feet below the valve again. You can also achieve this by rolling onto your back or doing a full roll, as long as your feet get lower than your upper body.

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 in a rapid ascent..
TThis can be corrected by arching your back and kicking hard to get your feet below the valve again. You can also achieve this by rolling onto your back or doing a full roll, as long as your feet get lower than your upper body.

6. Other exposure protection equipment

Apart from the dry suit, other diving equipment is similar to what you would be using when in a wetsuit.

As the dry suit finishes in the neck and wrist seals, we also need a hood and gloves to provide exposure protection for our head and hands. We use thick 7 mm neoprene hoods and 3-finger mittens to keep our head and fingers warm during the snorkel. As the hood and gloves are neoprene and outside of the dry suit seals, they are designed to slowly fill with water in the beginning of the dive. Then similarly to a wetsuit, your body will warm up the thin layer of water between the neoprene and your skin, and neoprene will insulate it to keep it warm.

Dry suit diving opens up a big range of new and exciting dive sites different to the mainstream dive sites in the warmer climates. It‘s an amazing new world that‘s waiting to be discovered.

Don‘t feel overwhelmed by all the information. Take in what you can, and our guides will go through all these either on your course or in the dive briefing. ☺ If you have any comments or questions, please contact us at We look forward to diving with you.
Your DIVE.IS team