Diving suit: Everything you need to know
Table of Contents
- What is a diving suit?
- Types of diving suits
- Choosing your suit
- Care and Maintenance
- Common issues and mistakes
- Price range
If you're here, it's probably because you like diving, or at least, you're interested in diving. When learning about diving, one of the topics we learn about is the limitations, such as the air reserve we should leave in our tank before ascending, respecting the no-decompression limits, etc... But one of the less obvious limits diving poses is the rapid loss of heat: As water conducts heat more efficiently than air, your body, when submerged, loses heat (and energy) faster! To be more exact, your body loses heat about 25 times faster when submerged.
To counteract that loss of heat, divers use specialized suits to keep them warm! Let's dive (no pun intended) into what diving suits are exactly and how to choose the perfect suit that meets your requirements!
If you're interested in learning more about the equipment scuba divers use, check out this article, which talks about all the equipment pieces.
What is a diving suit?
A diving suit is a garment that you put on yourself to keep you warm during your dive! As we'll see later, there are many different types of diving suits, and they can be made out of many different materials. The most common material for wetsuits is neoprene. Drysuits (we'll talk in more detail about them later) can either be made of neoprene or Trilaminate. Due to their material, they are positively buoyant and will require extra weight for you to be able to descend.
On top of providing thermal protection, a diving suit can give physical protection to the diver from elements such as stinging corals, jellyfish, and sharp edges on wrecks!
Let's have a look in detail at what different kinds of suits exist and in what situations each of them is best used for.
Types of diving suits
We can separate suits into three categories: Wetsuits, Semi-dry suits, and Dry suits. Some people classify the suits into two categories only: the suits that let water in (wetsuits, semi-dry, shorty, etc), and drysuits. Some people refer to semi-dry suits as wetsuits. For the sake of explanation, however, I will separate wetsuits and semi-dry suits into two different categories.
Wetsuits
Wetsuits are the simplest and most basic suit type. They are tight along the body and warm up the water in contact with the skin, limiting its flow. Although the flow is limited, it is not completely restricted, and new water could flow in with the wrong movement of a limb.
Wetsuits can have varying thickness, providing more or less thermal protection. The thickness of a typical wetsuit will vary from 3 to 7mm. While 3mm is suitable for diving in a warm and tropical location, 7mm is typically used for moderate temperatures (usually between 20°C/68°F and 25°C/77°F). It is usual for wetsuits to lose thickness over time and become thinner after prolonged use.
Semi-dry suits
Semi-dry suits can be recognized by their water-tight zippers, seams, and seals on the limbs. The idea behind those suits is that water is allowed to flow in, but not out; and because the water that is in contact with your skin (and is heated up by your body heat) is always the same, you stay significantly warmer. A misconception divers have with semi-drys is that they will keep you drier than wetsuits; this isn't true, and you will still get wet (as you normally would going in water) in a semi-dry suit!
A semi-dry suit is usually thicker than a wetsuit due to the nature of its use in more temperate/colder waters. A typical semi-dry suit will have a thickness varying from 5.5 to 8mm. The thickest semi-dry suits can be used to dive in water as cold as 10°C/50°F (although we wouldn't recommend staying too long at that temperature without a drysuit.
An issue divers might have with semi-dry suits compared with wetsuits is that they feel more constrained and "enclosed".
Drysuits
The Drysuit, often considered the king of diving suits, is the most advanced type of suit available on the market. Compared to the semi-dry, there is no confusion: the drysuit will keep you completely dry.
There are multiple options when choosing a drysuit: The first variant is the material the suit is made out of; the two choices presented to you are either a Neoprene drysuit or a Trilaminate drysuit. Neoprene drysuits keep warmer and are cheaper, but trilaminate drysuits are more durable, and add less positive buoyancy. If you are getting yourself a trilaminate drysuit, you will have to get yourself some thick undergarments, as the suit by itself will keep you dry, but won't heat you up! Another popular option is the integrated wrist ring, which allows the diver to screw on/off dry gloves, to keep their hands dry.
Drysuits are used for cold water, up to sub-zero temperatures (yes, in certain specific conditions, water can stay liquid under its freezing point!); they are also used for contaminated spots such as dirty waters for public safety diving (where the diver will have to recover decomposing bodies); and specific dives such as technical and cave dives, where the diver needs an alternate and independent buoyancy-controlling piece of equipment.
Drysuits require an inflator hose connected to them to be inflated to counteract the increasing pressure from the depth (otherwise, the diver would get a so-called suit squeeze!). Because they can be used as buoyancy compensator devices, diving in a drysuit is considered an entirely different type of diving and requires special training.
Other
- Long Johns were an older kind of wetsuit, but aren't commonly used anymore. They are a one-piece suit covering the legs and the torso, leaving the arms exposed; they allow more ample movements and dexterity for the diver.
- Shorties are additional garments that don't cover the legs and the arms completely (like a shirt and shorts in a single piece), but can be added under or over a wetsuit to add additional thickness, which keeps the diver warmer. In warm water, it is possible to dive only in a shorty.
- Rash guards are swim shirts that can be worn alone or under a suit. Their primary purpose is to offer protection from the sun, as some can be integrated with an UPF rating of 50+. For colder weather, rash guards can also offer extra thermal protection.
- Hood, gloves, and boots are accessories that can significantly improve thermal protection: The body loses a significant amount of energy through its extremities, and keeping your hands, feet, and head warm can make a big difference! Wearing gloves, however, (especially thick gloves), is known to reduce dexterity, which can be an issue when you need to do things with your hands, such as handling stages, tying lines, etc...
How to choose the proper diving suit
Choosing the proper suit is a multi-factor choice depending on your comfort, where you plan to dive, the type of diving you will do, etc... It is important to make sure that you use the correct diving suit in the correct situation to make your diving experience as enjoyable as possible! Let's have a look at the different options and what suit you should choose, depending on the situation:
Wetsuit Vs. Drysuit
First of all, let's make the choice between a wetsuit and a drysuit. A wetsuit is only adapted to warmer weather, while a drysuit is more versatile. However, a drysuit is bulkier and heavier, making it more tricky to travel with. In any case, let's have a look at the recommended temperature range where you would need to use a drysuit or a wetsuit.
- Between -1°C and 10°C (30-50°F): your only option is a drysuit, as a wetsuit (or a semi-dry) won't keep you warm enough
- Between 10°C and 20°C (50-68°F): we recommend either diving in a drysuit or using a thick (ideally 7.5mm) semi-dry suit. Alternatively, a wetsuit, with a shorty on top, thick hood, and gloves, might keep you warm enough for a limited amount of time.
- Between 20°C and 25°C (68-77°F): we recommend diving in a thicker wetsuit and a hood. You can still use a drysuit for longer dives!
- Between 25°-29°C (77-84°F): A simple 5mm wetsuit will be enough to keep you comfortable. At this temperature, using a drysuit will start to become uncomfortable due to the heat.
- Above 29°C+ (84°F): At these temperatures, a lot of divers don't even bother putting on a wetsuit, as they dive in simple swim shirts such as rash guards. Be careful, however, although you might not feel it at first, your body is still losing heat and energy.
If you are diving deeper or doing technical dives, a drysuit is heavily recommended, as if there is an emergency, with your primary buoyancy device, you need a redundant piece of equipment that can make you buoyant again (and drysuits can!).
Wetsuit Thickness Guide
If you opt for a wetsuit, you will notice that there are multiple options when it comes to the suit's thickness. The thinnest wetsuits and standard shorties will have a thickness of 3mm, while the thickest ones can be as thick as 7+ mm. Although the use of a specific thickness can depend on many factors, such as comfort level, body weight, or even activity level, the following table attempts to give a general guideline to what thickness you should use depending on the temperature:
| Temperature (°C) | Temperature (°F) | Wetsuit Thickness |
|---|---|---|
| <10°C | <50°F | Drysuit required |
| 10°C-15°C | 50°F-59°F | 7mm long wetsuit + 3mm shorty, Hood and gloves recommended |
| 15°C-20°C | 59°F-68°F | 5mm long wetsuit + 3mm shorty, Hood and gloves recommended |
| 20°C-25°C | 68°F-77°F | 5mm long wetsuit |
| >25°C | >77°F | 3mm wetsuit/Rash guard or Lycra |
Neoprene Vs. Trilaminate drysuit
If instead of a wetsuit, you choose a drysuit, you will have two main options available to you: Neoprene or Trilaminate drysuit. They are both good for their own purposes; if you are interested in the key differences between the two types, have a look at the table below:
| Neoprene | Trilaminate | |
|---|---|---|
| Pros |
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| Cons |
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Some dry suits are reinforced with Kevlar to make them even more resistant to scratches and tears!
Care and maintenance tips
Wetsuits: rinse the inside and outside of your suit with freshwater, hang up in a dry and cool area, do not expose directly to the sun for a prolonged duration, as it harms neoprene.
Drysuit: Rinse the outside of your suit, or ask someone to spray you with freshwater while you are still wearing the suit! If some water/moisture got into the suit either during the dive or as you washed it, hang it upside-down (there are specialized hangers allowing you to hang to suit by its boots) to get rid of any water that could potentially stay inside: water left inside your drysuit will stagnate and cause bad smell.
If you dive often, it is good practice to let your wetsuit dry before reusing it. If you dive very often, we recommend getting yourself two wetsuits and cycling between them between each use, letting the other one dry up before reusing it. Doing so will make your two wetsuits last longer than if you bought one after the other and used them individually!
Common mistakes and issues with diving suits
Incorrect weighting: Diving suits are positively buoyant, and the thicker they are, the more buoyant they are. This means that you will need more weight to be able to descend if you are wearing a thicker suit. Before the dive starts, we recommend carrying extra weights on the side to add to yourself if you are not able to descend! You should also know that a brand-new suit will be more buoyant than a used one.
Suit squeeze: A squeeze is a physical phenomenon that happens when an air space gets compressed by an outside increase in pressure. As diving suits can hold air spaces in them (either drysuits being completely waterproof, or semi-drys trapping a bit of air in a crease or a fold), they are subject to squeezes: Suit squeezes are categorized by a contraction of the suit, making it tighter and tighter the further down you go. An easy fix is to release the air bubble if you are using a wetsuit, and to inflate the suit if you are using a drysuit.
Price range
Wetsuit: A thin, entry-level wetsuit can be found for as low as 100€, while the more expensive, thicker ones will run you around 500€.
Semi-dry: Semi-dry suits will range anywhere from 300€ to 700€, depending on the quality, thickness, and other factors.
Drysuit: The cheapest Neoprene drysuits can be bought under 1000€, while the cheapest trilaminate will run you between 1500-2000€. The most expensive drysuits (often trilaminate, tailor-made) will cost upwards of 3000€.
FAQ
Q: What to wear under your diving suit?
A: You can wear whatever you want under your diving suit, as long as you realize that if you are using a wetsuit, you will get wet! In this scenario, we recommend using a simple swimsuit or a Lycra shirt underneath. If you are using a drysuit, we recommend wearing specialized undergarments that will keep you warm.
Q: How heavy is a diving suit?
A: A modern diving suit is not very heavy (a few kgs for the heaviest drysuits and less than a kg for the thin wetsuits) compared to the older diving dresses, which could weigh upwards of 80 kgs!
Q: How fast do we get hypothermia without a diving suit?
A: It depends on the temperature of the water! For water colder than 10°C, you will get hypothermia in 10-15 minutes, while in more temperate conditions of 20°C, you could last 1-2 hours before hypothermia sets in.
Q: Can I scuba dive without a suit?
A: Although in warmer climates, people have been diving without any suit, we still recommend wearing a protective layer, such as a rash guard/Lycra shirt, to protect against the natural elements. If the water is colder than 26°C, we strongly recommend wearing a thermal suit.
Q: Do I need a hood/gloves?
A: Hoods and gloves are extra accessories, and are not necessary; however, if you feel cold during your dives, having them will help you feel warmer.
Q: Do I need a certificate to dive drysuit?
A: Although some places will require you to have a drysuit certificate to use it, it is generally not necessary to have it prior to purchasing and using the drysuit. Of course, we still recommend being trained with the equipment you use and therefore are advocates of taking a drysuit course when using one for the first time.
Q: Can I pee in my suit?
A: Yes, if you can not hold it during the dive, you can pee in your suit, although we really don't recommend doing it in a semi-dry or a drysuit! For obvious sanitary reasons, just make sure you wash your suit thoroughly after the dive.