Exposure protection - making decisions on your diving Part 2
When it comes to diving, there are a lot of choices available to help combat the cooler temperatures. In the first part of this two-part series, we discussed wetsuits and the benefits of owning a good quality suit; today, we'll talk about the moment one may need a little more protection because of the environment. In order to ensure the comfort level of the diver is maximized, some may choose to purchase a semi-drysuit or drysuit. As with wetsuits, there are many styles to choose from along with features and benefits to enhance the diving experience.
A major difference between a wetsuit and a drysuit is the fact that one allows the water to enter close to the body (providing warmth through body heat) while the latter is designed to keep water away from the skin altogether. Through the creation of an air layer between environment and flesh, a drysuit allows the diver to provide further layers that will aid in keeping them toasty warm while executing their dive plans. The semi-drysuit is made of comparable materials, but it is not designed to keep water completely away from the diver's body.
As we know today, the core of our body releases a massive amount of energy compared to our appendages; by keeping this core warm, we'll experience a safe dive that doesn't include shivering as part of the task list!
Drysuits vary in the actual manufacturing process along with many accessories to add for the diver's comfort and needs. Here are some general aspects of drysuits and how to select a proper one.
A favorite style of drysuit diving is ice diving, where one can wear their mask on top of the head!!
Drysuits can be created through multiple methods. Generally speaking, they are lumped into two categories; neoprene and membrane.
Neoprene is a form of synthetic rubber that is utilized in wetsuits. Neoprene can be manipulated during the manufacturing process to create multiple forms of drysuit material that help keep the cool water off the body.
Foamed neoprene (also known as foam neoprene) is a process that creates a high amount of gas bubbles in the manufacturing process. The resulting material creates a buoyant suit with thermal insulation that keeps the water from entering the material. One of the advantages of this type of suit is that if it does flood, the diver will still get quite a bit of thermal insulation as the suit will still have some of the characteristics we see in wetsuits.
The neoprene line of drysuits are generally heavier than most and they also get skinnier with depth as the air bubbles shrink with the surrounding pressure. This would normally result in loss of heat, but it is mitigated with proper undergarments designed to retain heat close to the body.
We will also find semi-drysuits in this category. The material is not completely sealed, but it does trap a great deal of water seepage and creates a layer of water that is much warmer than the wetsuit. These suits can be a little cheaper, not include certain features, but be a good choice to keeping warm in a cool environment. A good example of a semi-drysuit is the Hollis Neotek, where gussets and sealed stitching restrict the flow of water on the skin and provide a layer of warmth through the processed foam neoprene.
Another form of the neoprene drysuit is the crushed neoprene suit. This is a suit that is hydrostatically compressed during the manufacturing process and almost completely eliminates the gas bubbles. This does not retain as much insulation, but it does result in a tough material that withstands changes to pressure and provides the diver with a suit that is sure to last for many, many years.
Not everyone enjoys the weight of these type of drysuits and will seek out other types to accompany them on their dive excursions. The membrane line of suits are made of much thinner material and provide little insulation like their cousins. They are commonly referred to as Trilaminate or Cordura. Manufacturers find new and improved ways to create these suits using laminated materials like nylon, butyl and vulcanized rubber (hence the Trilaminate name). A fabric aficionado will call this stockinette fabric. A majority of these fabrics are not flexible, so manufacturers will oversize them a little bit to provide some range of movement for the diver. For the diver, it makes these types of suits very easy to put on as they are similar to a baggy pair of jeans. A good example of this type of suit is the Fourth Element Argonaut 2.0. The materials are tough, reinforced with kneepads and other accessories to make a proper fitting suit for the diver.
With these type of suits, a diver will need to wear an undersuit. If they go with just a pair of shorts and tshirt, it won't take long for them to feel the effects of the environment and begin to shake from the cold. Making undergarments an essential component to drysuit diving in cool waters.
These suits are capable of being punctured or torn, so it is important that whatever material a diver picks should be cared for as with any other investment made with this sport. An underwater flood can affect buoyancy control, so it is important for a diver to visually inspect their drysuit materials and ensure nothing is leaking prior to the dive. Through proper cleaning and inspection, a drysuit will last a drysuit diver for many years.
Neck and wrist seals
A critical component of a drysuit is the quality of the neck and wrist seals. These items are made of neoprene or latex and rest against the skin of the diver. Excessive hair, tendons that stick out along the seal (like the transverse carpal ligament) or other obstructions can affect the proper seal on the suit and provide for a leak. In some models, these items are sewn directly to the suit and are given the utmost care by the diver as a torn seal could mean the cancellation of a dive. These seals are prone to tears from fingernails, improper donning/doffing and coming into contact with the environment (i.e. hitting the reef). There are two types of seals on the market.
Latex seals are thin. They are a delicate version, but they do provide the most effective seal as they 'stick' quite well to bare skin. These provide a blockage of water entering the suit and help the undergarments and the suit perform as designed.
Neoprene seals are thick. They are a little bit tougher, but are still capable of tearing. The thickness of the material does provide an effective seal and even a bit of warmth to the contact area against the skin. If the diver is rough on things or cannot get a great seal with latex, they might want to try the neoprene option.
A newer technology is the user-replaceable models of seals. These are plastic or delrin designed attachment points on the suit itself that provide interlocking pieces. Having these items in the user-replaceable category means that a diver can carry back-ups in the event they tear a seal prior to the dive. It also means that the suit will not need to be sent to the manufacturer for replacement; a process that can take up to 4-6 weeks. Many divers find themselves selecting this upgrade to ensure their diving days are not interrupted by a torn seal!
Another great technology is dry gloves. These gloves further resist water entering the hands of the diver and they also allow the diver to place a warming layer to ensure their hands do not get cold on a dive. Though a little bit of dexterity is lost, they do provide a great deal of warmth and the ability to self don.
These seals are also trim capable. Meaning that one can properly fit them to the neck and wrists. They should be snug to the skin, but not so snug that it cuts off circulation to the head or hands. Utilizing a surgeon's care with a razor blade and a plastic bottle can provide the background for cutting these seals properly. A suggestion would be to trim one line at a time when trimming these for the first time. Divers will not want to over-cut these items as they will have to replace them if a mistake is made. If one has shaky hands or are in a hurry, it's also a good idea to seek out the help of a professional who cuts these seals on a regular basis. An uneven or erratic cut could create a future weak point on the seal itself.
Which type would be better? That's really up to the diver. As with any investment, the diver must look towards what type of seals they would want to add to the suit in order to ensure a long and comfortable life diving in their specific environment. A diver should also consider the change in material if they have a latex allergy, they may find the neoprene seals more advantageous.
Due to the fact that a drysuit has an air pocket created from the layer between the environment and the flesh, divers find themselves needing the ability to add or vent air for given situations. As we know from our Open Water dive courses, air expands and contracts when we are going up or down respectively. This effect means that the suit will contract to the body or possibly get too much air inside of it and affect our buoyancy control. Alas, there's a solution!
Every drysuit has an inflation and deflation capability built into the suit through valves that are designed to work with the scuba kit and the diver. The inflator valve on a suit is typically found in the center of the chest. This is brought into operation through the use of a low pressure inflator hose similar to the one found on a BCD. A diver who experiences a squeeze or needs to control their descent can add a little air to the suit in order to exercise some buoyancy control. Having this extra air layer will require the diver to add a little weight compared to a wetsuit diver. Which is why it is imperative that the diver does a buoyancy check if they are in a new environment.
Since we have the ability to add air to the suit, the diver will need the ability to dump air as well. This is done through an exhaust valve. Most models will put the exhaust valve on the left shoulder of the suit. When the valve is in the open position (this is a righty-tighty, lefty-loosey situation) it will let air out anytime the air reaches the shoulder of the suit. When it is it closed, the diver has control over the venting of the exhaust valve. In some training circles, the instructor will advise the diver to close this during descent so they can comfortably get buoyancy control as they descend. Prior to the ascent, the diver can open the valve to safely release air and prevent an uncontrolled ascension.
These valves can be moved on custom suits and they do make models with extra exhaust valves for the diver. For example, a diver may choose to put exhaust valves on the ankles to prevent the air going into the feet and causing an unintentional inverted ascent.
Whatever choice is made, it is important to freshwater wash these valves after every dive to keep them from freezing open. Having this occur could cause a leak in the suit or an uncontrolled buoyancy situation.
The absolute best part of a drysuit is the ability to add warming layers to the skin! Keeping the core toasty warm allows divers to push well into waters that they would not have survived in with just a wetsuit. Hypothermia is a real concern when we are in the water and being able to invest in some nice undergarments will help us enjoy diving to the fullest!
There are all kinds of types of undergarments out there. When selecting a proper undergarment, it is a good idea to investigate the type of material. Most drysuit divers will enjoy a material that provides a great deal of warmth without too much bulk. Another great feature is the ability to wick; if one is sweating or if water does get into the suit, it is nice if the undergarment can continue to keep warmth by getting that water away from the diver's skin.
A good tip for selecting an undergarment is to look at the manufacturer's recommendation on temperatures. Some will actually offer a base layer along with another layer that one could use in cooler waters. For example, during the summer, a base layer may be just fine to wear while diving; then in winter, we add another layer to keep toasty warm on those cooler dives.
Yes, someone could grab a pair of jogging pants and a sweater out of the closet to provide warmth, but keep in mind that these materials are not made to withstand compression. The hydrogen bonds within these materials will break down and not provide the type of warmth compared to a drysuit undergarment designed for this purpose.
The drysuit is pretty easy to master, but it is equally important that the diver receive some sort of training on the suit before taking it on dives. A quality instructor will teach the drysuit diver how to deal with emergency procedures and help master the buoyancy characteristics of the suit. One will find that through proper training, a diver will be able to comfortably enjoy drysuit dives for many years to come! Most training organizations will conduct an academic session with and then head to confined water to master some skills one will utilize on two dives in the ocean. Just like any new piece of equipment, do not be deterred by not mastering buoyancy on the first couple of drysuit dives. As with any other dive in the ocean, the diver be able to don and doff quickly as well as be a master at buoyancy control while they dive more often!
The diver above is sporting dry gloves and a hood to accompany the cooler waters of Washington State!
Diving in our local Southern California area may require some sort of drysuit training and use for winter divers. A drysuit will most certainly keep the diver warm in cooler waters and will provide years of use when a diver decides to invest in one. A lot of divers will be a little shocked at the higher investment point of a drysuit, but it should be done with the understanding that the individual will own a drysuit far longer than a wetsuit. The suit will also have a much longer warranty period when it comes to manufacturer help on repairs. Hopefully, as the reader moves into the market of a drysuit, you'll enjoy one for years and be able to reach new dive sites that were formally limited to you because of a wetsuit!
About the Author:
D.J. Mansfield is a PADI Course Director who dives Southern California and has done so for 22 years. He is currently the Director of Operations for Beach Cities Scuba and is a committed ocean steward and trainer for divers all over the world.
Follow him on Instagram @djmansfield7or contact him at email@example.com.
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