Choosing a water exposure suit
By Andrea Zaferes and Walt “Butch” Hendrick
Contaminated water diving course: “bring your own wetsuit.”
When we read advertisements like this we cringe and then realize it’s time to write another article.
The one mission that must be successfully completed one hundred percent of the time is “when the operation is over you need to go home”. Proper personal protection equipment (PPPE) is vitally important to the success of that mission, with exposure suits being one of the most important pieces of PPPE for water operation personnel.
When choosing an exposure suit the first question to ask is what kind of water do you need protection from? Is the water contaminated, cold, full of debris, moving, or a combination of these variables? The next decision has to be what do you need the suit for? Will it be for public safety diving, swiftwater operations, surf rescue, boat or personal watercraft operations, or surface ice rescue? Other questions to ask include, what are the budget constraints, how many technicians and operations personnel need to be outfitted with suits, what is the turnover rate for team members, and how often will the suits be used?
Contamination is an important consideration that is often overlooked when the district’s water is not currently contaminated. Floods, run offs from heavy rains, biohazards from bodies, creosote from pilings, and petroleum products from submerged vehicles can turn clean water into a hazmat situation. Too often we hear technicians say that they do not need drysuits because they have warm water and they would overheat. Proper procedures can prevent heat exhaustion, but only hazmat tested drysuits can protect technicians from contamination related illnesses.
Cold can also be a misunderstood variable. Water conducts heat twenty-five times faster than air. We lose heat at the same rate in 42 degree F air as we do in 80 degree F water.1 Some divers consider a wetsuit effective protection for winter water operations because they do not become cold easily, but are they considering what happens when they have to first sit as a 90-percent ready diver2 and then as a back up diver, prior to serving as a primary diver? Even surface rescue personnel must be prepared for unusually long operations and atypical weather conditions.
Everyone reacts differently to cold exposure and should be dressed accordingly. What is good for one team member may be completely insufficient for another. A navy study of the effects of immersion found that a higher level of body fat reduced the rate of rectal temperature loss.3 A 110 lb person losing heat at the same rate as a 250 lb person will most likely have a lower core temperature than the larger person. A study of 8 Navy combat swimmers in 6o C water showed that “each diver appears to have a particular core temperature decline profile with respect to cold water exposure.4
For example one diver may be perfectly comfortable using wetsuit gloves, while another will feel pain in 15 minutes while wearing an insulated dry glove. A previous cold injury can increase susceptibility to cold problems, even if the original injury was many years earlier. Individual differences between ability to withstand cold can be great and should not be ignored, especially in the “grin and bear it” atmosphere of police and fire personnel. Technicians and surface support should be observant of individual cold stress susceptibility of themselves and of their teammates. This means that if the team captain has been ice diving in wetsuits for twenty years without becoming cold that does not mean that wetsuits are acceptable for other team members.
A large percentage of outdoor drownings occur in water not designated for swimming, which means that trees, rocks, garbage, and other debris can be a real concern. Divers often must search in low or zero visibility water, forcing them to be bottom dwellers searching by feel. Ice rescue technicians may come in contact with spider wire and fish hooks, while swift water technicians may be pushed into sharp rocks or branches from strainers.
Once enough information is gathered about environmental variables, the team’s needs, and department budget constraints, the next decision is what kind of suit is necessary? Most noncommercial divers wear passive exposure suits, meaning that the suits do not provide a heat source to the wearer, rather they provide insulation between the wearer and the environment. Active exposure suits are more commonly found on commercial diving sites and typically involve hot water suits. Public safety personnel can manage with passive suits because their in-water times should be much shorter than those of commercial divers. Passive suits are self-contained and far less expensive than the actively-insulated suits that typically burden divers with an umbilical and the need for highly trained water and surface support personnel.
There are, however, battery powered heating units on the market that are designed to be worn under drysuits by divers who move very slowly looking for small search objects in low visibility water, for divers who stay in one place for periods of time conducting research, or for ice divers who sit through the 90-percent ready and back-up diver positions before acting as a primary diver. Active heaters can also be helpful for divers who feel the effects of cold quickly, such as some women and individuals with little body fat.
Passive suits fall into two main categories, wetsuits and drysuits. Wetsuits help keep divers warm by trapping and insulating a layer of water next to a wearer’s skin. That layer is warmed by the diver’s body heat. The wetsuit itself is a spongy material with thousands of gas bubbles inside, which are the insulation that traps body heat. Increased suit thickness will increase the degree of insulation. If the suit does not fit well then cold water will replace the warmed water and heat loss will occur.
Drysuits, which can be made of several types of materials, encapsulate all parts of a diver’s body but the face and sometimes the hands, where wrist and neck seals prevent water from entering the suit. Surrounded by a layer of air in the suit, the wearer therefore stays totally dry, and is able to wear warm, insulating underwear beneath the suit. To compensate for the compression of the air in the suit as the diver descends, diving drysuits have a power inflator much like that of a buoyancy compensator device (BCD) and an exhaust valve to release air during ascents.
Too often teams make the mistake of purchasing wetsuits instead of drysuits solely because of cost differences. With decreasing national and local water standards most water operation teams have contaminated water in their district. In the long run, an incorrect purchase of wetsuits will be more costly when they later end up sitting on a shelf after being replaced by drysuits. It is better to start out purchasing three good quality drysuits than it is to purchase six wetsuits, if drysuits are the better choice of PPE.
Let us look at some of the benefits and disadvantages of wetsuits and drysuits to help make the decision of which best meets the needs of your team.
- Relatively inexpensive to purchase
- Require little training to us
- Relatively little maintenance required
- Not sufficient for cold air or water temps.
- Proper fit required for thermal protection
- Offer no protection against contaminated water
- Thin suits offer little protection from debris
- Are damaged by common contaminates
- Insulation decreases with increased depth due to suit compression
- Can take many hours to dry – require heated environment to dry
- After use, cannot quickly be put back in service in a vehicle
- Take longer to don
- Cannot be worn over clothing
- Are less forgiving when wearers change their size and weight over time
- Requires thin suits for warm water and thick suits for cold water.
- Can cause serious evaporative heat loss when worn wet on land
- Wearers are soaking wet on land after suit removal – heated shelters are required to rehab in colder climates
- Will freeze when left wet in cold air temps
- Cannot be easily patched on scene, and must be dried prior to applying a patch
- No way to cool wearers wearing thick suits on land
Drysuits in general
Offer excellent cold water thermal protection
Undergarments and added air can be adjusted for all season use
Some drysuits offer excellent protection from contaminates
Require a little more maintenance
Can be more readily adapted for use by different sized individuals
Except for full thickness neoprene suits, drysuits have no intrinsic positive buoyancy so a PFD is required when working on the surface without a BCD
Allow for rapid donning
Can be worn over street clothes
Air can be added to maintain insulation with increasing depth
The wearer remains dry
Adult diapers can be worn during longer operations
Can offer superior protection against punctures and other injuries from debris
Allow wearers to be cooled on hot days on land by venting with the inflator valve
A quality suit can be costly
Require certification training to use
EPDM Vulcanized5 rubber, hazmat-tested Drysuits
Are intrinsically negatively buoyant so less lead is required to be neutral
Are generally the most costly suits
The PPPE of choice for hazmat diving
Can be towel-dried in between dives to prevent freezing
Can be towel-dried and immediately put back into service after use
Easy to clean, even when exposed to many contaminates
Can be worn over street clothes
Can be quickly patched on scene, even after being wet
Wetsuits are not suitable for water colder than 50o F, so they are not appropriate for year-round use in colder climates. Wetsuits allow water to be next to a wearer’s skin so they offer no protection whatsoever against contamination. Additionally, petroleum products and some other contaminates break down the neoprene rubber of the suit, causing it to disintegrate. The fabric covering wetsuits also tends to trap body tissues and fluids from corpse recoveries. Once wetsuits are contaminated, they are virtually impossible to clean. Hence, if wetsuits are used, they should be used with caution, and only in clean bodies of water.
A good drysuit with appropriate winter-weight undergarments and a layer of air, will keep the diver’s skin and core temperatures at normal levels at normal ranges for the duration of an average ice dive. A hazmat tested drysuit will protect wearers from contamination if an appropriate breathing apparatus is used.
As we can see, drysuits are the best choice for teams who work in cold or dirty water. If drysuits are chosen, then the next decision making process is choosing the right drysuit for the teams needs. Divers have the most stringent needs when it comes to drysuits, so we will address the needs of public safety divers first. Several of the needs of surface personnel and divers are the same when it comes to drysuits, so surface personnel will find the following information useful as well.
The myths of drysuit diving
Many divers and dive teams have false beliefs about drysuits that prevent them from taking advantage of the benefits of drysuits. Below are several such myths, followed by the reasons that they are untrue.
Myth #1: Drysuits require more weight than five or seven millimeter drysuits. In reality, a properly-weighted drysuit may require the same or even less weight than a thick wetsuit. The key is to first stretch fully upwards and downwards, and then burp excess air from the suit by kneeling with the left knee up, while holding the neck seal away from the skin with the left hand and pushing the exhaust valve with the right hand. The result will be that the suit sits properly and contains minimal air.
Myth #2: Drysuits are more restrictive to movement than wetsuits. A properly-fitting drysuit should allow full range of motion. Additionally, because they do not need to fit as tightly as wetsuits, drysuits can be more comfortable and less restricting.
Myth #3: To vent a drysuit that is self-inflating, pull the neck or wrist seals out to allow air to escape. While this procedure certainly sounds good, reaching through a hood or wrist seals while wearing gloves is not so easy. Instead, if your inflator is stuck, first disconnect the hose, then dump air through the arm-mounted exhaust valve as you flare out to slow your ascent and continue breathing normally..
Myth #4: Drysuit divers do not need to wear buoyancy compensators (BCD’s). While this procedure was commonplace years ago, it has been discarded. Drysuit divers should wear BCDs to allow them sufficient flotation on the surface with a flooded suit, to allow for neutral buoyancy when carrying a recovered victim, and to compensate for depth-caused buoyancy changes.
Myth #6: Use the drysuit to control buoyancy rather than the BCD . There are many reasons why such a practice is a safety hazard, including increased risks of carotid sinus reflex, free-flowing suit inflator valves, inverted ascents, uncontrolled ascents, and poor buoyancy control.
Myth #6: A flooded drysuit will cause a diver to sink. Water weighs the same whether it is in or outside of the suit. A diver only becomes negatively buoyant in a flooded suit if the diver is over-weighted and if the diver was using the drysuit, rather than the BCD, to control buoyancy. In reality, the only dangers of a flooded drysuit are contamination and hypothermia.6
Myth #7: Divers do not need a drysuit course and certification to dive in a drysuit. Drysuits are a unique piece of equipment that require training and practice to use safely. Lack of training can result in dangerous overweighting, carotid sinus reflex, uncontrolled ascents, drowning, and decompression illness. Mandatory drysuit certification is a diving industry standard that must be met.
What to look for in a diving drysuit
Fit: There are a variety of drysuits on the market, but one key factor to all of them is fit. Drysuits that are too big require more air internally to fill the excess space, which increases the amount of weight needed to dive and decreases overall mobility. Suits that fit too tightly do not allow wearers to add enough air in the suits, which can result in restrictive compression in areas such as elbows, knees, shoulders, and spine. Such restriction can cause a serious lack of mobility and loss of circulation in the extremities.
Fit the suit with the thickest undergarments that may ever be worn, then bend down with hands reaching for the floor to make sure the torso is long enough. Stand straight with arms raised to the sky and make sure the crotch is not too low, which would mean that the torso is too long and possibly the legs are too short. If such is the case, fin kicking and walking will be more difficult.
With arms raised forward, make sure that the end of the suit material at the wrist does not extend beyond the wrist bone. Squat down to make sure that the legs are long enough. Lay supine on the floor holding the crotch in place and have someone pull on the boots. If the boots come fully off your feet then the legs are too long. If the suit legs are too long, then fin loss can occur in the case of accidental suit inflation with body inversion.
With the warmest undergarments on, the suit should fit well to every part of your body.
Material: Full thickness neoprene offers the most intrinsic insulation but it has several important drawbacks. It requires significantly more weight and significantly more time to dry, cannot be repaired wet on the scene, is more bulky to store, takes many hours to dry, is not acceptable for contaminated water, and is more difficult to clean. An advantage of full thickness neoprene suits is that they are usually less expensive than other drysuits.
Crushed neoprene suits, such as that made by DUI™ have much less intrinsic insulation than full thickness neoprene suits but they are often more comfortable, easier to store, require less weight, and require less time to dry. Crushed neoprene suits can be costly though, and have the same vulnerability to contamination, cause evaporative heat loss in air after immersion, and are as difficult to repair in the field as full thickness neoprene suits.
Tri and bilaminate suits require less weight, take less time to dry, are relatively easy to repair on scene when dry, and take little room to store, but they offer no intrinsic insulation. The durability of laminate suits and their ability to protect a diver from contamination varies widely depending on the manufacturer and type of suit. Be wary about low priced suits because you will often get just what you pay for.
EPDM vulcanized rubber suits require the least amount of weight because they are intrinsically negatively buoyant. Less weight means less compensation for depth with the BCD, better buoyancy control, less risk of uncontrolled ascents, and safer diving. Rubber suits can be immediately repaired on scene even after immersion.
Vulcanized rubber suits can be simply toweled off and then rolled for storage. They are the only suit that does not require any time to be hung to dry, which is a real plus for public safety divers who can simply replace the suits in their proper place for the next call. This ability to towel the suits dry is also a great advantage for ice divers because the suits wont freeze between dives if there is no shelter, and divers can keep the suits on after a dive since there will be no evaporative heat loss. If suits are shared between divers, the next diver can don a dry drysuit. These abilities are particularly important for dive teams who do not have the time or ability to set up heated shelters.
Viking Trellerborg? manufacturers vulcanized rubber suits that were the first to be approved by a rigorous series of testing with a multitude of contaminates. They used the National Fire Protection Association (NFPA) 1991/1994 edition of the standard for vapor protective suits for hazardous chemical emergencies and the American Society for Testing and Materials (ASTM) F1001 standard guide for chemicals to evaluate protective clothing materials, 1989. “It also should be mentioned that the only approval mechanism in place in the world today which does deal with standards of a diving suit, is CE95 0403. These are standards to which Viking is certified after passing through examination procedure in accordance with the Personal Protective Equipment Directive 89/686/EEC (PPE), class 3, which is the highest class with the toughest demands of the European Union.”7 If contaminated water is a potential or realized concern then we recommend reading, Diving In Contaminated Water8, which includes the most comprehensive test data available on any drysuit for diving in contaminated water. Before purchasing a drysuit, ask to see data on testing results for contaminated water.
Vulcanized rubber suits are the easiest to clean thoroughly because of their impermeability to contaminates. In regards to durability, some high quality bi or tri laminate suits may be more resistant to punctures and abrasion than are vulcanized rubber. Neoprene and crushed neoprene suits offer the least protection from punctures.
Suits made with material that stretches is usually more comfortable than suits that cannot stretch. If the suit will be used for rescue swimmer operations, then a stretchy material can be an advantage. Viking Trellerborg™ recently developed a hazmat tested EPDM vulcanized rubber suit with a stretchy backing to provide all the advantages of EPDM rubber along with the mobility offered by a suit that stretches.
Zippers: Not all zippers are of the same quality. In regards to drysuits you typically get what you pay for. Ask what grade of zipper is installed in the suit. A heavy duty zipper has fewer teeth per inch than less durable zippers, and has a better backing material.
A never-ending controversy is which is better, a front or back-entry zipper? Back-entry suits are usually more comfortable and easier to don. Tenders should open and close all zippers, whether they are back or front mounted, hence the advantage of a self-donning suit is irrelevant. Front entry suits often require a flap of material that is buckled down over the abdomen. This is one more step for donning and more suit material to fill with air. Front entry zippers require a protective flap over them since they are more exposed to bottom and water debris than are back zippers. Back entry zippers will last longer than front entry zippers because of the way the body bends.
Inflator and exhaust valves: Exhaust valves with a domed top are more preferable than flat-topped valves, because the former can be exhausted by raising the left arm up and pressing the dome against the left side of the diver’s head. This allows divers to disconnect a self-inflating drysuit hose with the right hand while simultaneously flaring and exhausting the suit. Check for valve quality because not all valves are created equal. A swivel feature in an inflator valve is good because it allows divers to position the inflator hose for the most effective and rapid disconnect move possible. The inflator valve should be pointed downward at a 45 degree angle, which is the most natural position to reach up and disconnect the hose in case the valve starts to self-inflate. Make sure the inflator valve is in a position that will not be obstructed by a diver harness or BCD.
Cuffs and seals: Heavy duty latex seals are especially important for cold or contaminated water, since both can increases the chance of latex tearing. Latex will tear easier than neoprene, but it can be toweled dry and is better for contaminated water diving. Cuff ring systems are recommended because a torn wrist seal can be replaced in less than a minute. If a wrist seal is torn and there is no cuff ring, then the suit will have to be sent out for a costly repair. Although cuff rings cost more in the initial investment, they can save the department significant money in the long run. Cuff ring systems also allow a greater variety of wearers to share the same suit.
If several users share a suit then the neck seal should be cut to fit the largest neck. Wearers with smaller diameter necks should first don custom made neoprene neck collar to increase their neck diameters.9 The suit neck seal then sits on top of the neoprene neck collar.
Drysuit undergarments: Divers typically under, rather than over, dress when it comes to undergarments. Always be prepared to be comfortable for twice as long as the planned dive time. Divers may need to remain as back-up or 90-percent ready divers for times longer than expected. If divers become overheated before serving as primary divers they can be placed in the water or they can be vented. To vent, have the diver pull the neck seal away from the neck while the tender hits the suit inflator button for ten to twenty seconds. This technique uses minimal air, but significantly decreases the temperature in the suit’s torso.
Make sure the underwear fits. If it is too tight it can restrict movement and blood flow. Even underwear that is too big can cause movement restrictions. For example, if the torso is too long, the crotch area may end up too low, making it difficult to kick well. Too large undergarments can bunch up in joint areas causing restrictions.
Avoid underwear with a great deal of compressibility, which will result in unnecessary and possibly hazardous buoyancy changes for depths below 2 ATA. Pile-type underwear for example will greatly compress with depth, making the diver heavier. The diver responds by adding air to the BCD or drysuit which makes buoyancy control more difficult and the chances of rapid ascents more likely. Another consideration is that undergarments lose their insulation value as they compress.
Choose underwear material that will work when wet to avoid divers becoming chilled if they exert themselves and perspire or if the suit leaks. Polar fleece and wool works very well. An acrilian pile undergarment was tested under an immersion coverall during immersion for one hour in 2.5o C water. Subjects without the undergarments lost 13.1 o C of mean skin temperature while the protected subjects only had a loss of 9.9 o C.10 Avoid anything cotton because once cotton is wet or damp, divers will quickly chill.
If a team faces cold winters and the budget only allows the purchase of one set of undergarments, then we recommend purchasing the warmest undergarments that the manufacturer offers. In warmer seasons divers can wear less expensive fleece sweatshirts and sweatpants, but it is hard to find replacements for artic-capable undergarments in the winter.
Hoods: We can lose more than thirty percent of our heat from our heads, yet hoods are the first PPPE most people opt to not use when the water is warm. The reason given for ditching hoods is almost always lack of comfort. Hoods are important not only for thermal protection but for protection from contaminates and debris. Another consideration is that cold water passing over the ears can result in vertigo, which can be potentially hazardous.
For hoods to be comfortable they must fit properly. If a hood is too tight it will be restrictive and uncomfortable, if it is too large it will offer less thermal protection as water enters and moves around the head. Drysuit hoods are constructed either of neoprene, EPDM vulcanized rubber, or latex. The latter two hoods do not offer intrinsic thermal protection and thus require an undergarment such a skull cap or preferably a firefighter Nomex hood. But the latter two hoods can be towel-dried which is important for preventing evaporative heat loss between dives.
EPDM rubber hoods offer the greatest protection against contaminates and hence should be chosen if divers must enter contaminated water.
EPDM rubber hoods and especially latex hoods require a fabric undergarment even in warm water to allow for ear equalization. Latex can create a seal over the outer ear canal that can result in serious injury if a skull cap is not worn.
Hoods can fill with air if full face masks are used, which is especially true for positive pressure masks. Neoprene and latex hoods stretch, so they can hold larger amounts of air than EPDM rubber hoods. Every pint of air is equal to a pound of buoyancy so an extra pint of air in a hood can be an uncomfortable nuisance. Hood vents placed at the top and back of the head will prevent this “cone-head” problem. Commercially made diaphragm hood vents are recommended for latex hoods. Neoprene hoods can be purchased with vents or can have homemade vents made by cutting a small “x” in a stretched-out section of the hood with a sharp, heated knife tip.
Gloves: Hands must be protected from cold, debris, and contaminates. Kevlar covered neoprene gloves are best for searching in debris-covered bottoms in clean, warm water. Dry gloves are required for cold and contaminated water. Cold hands can easily loose enough dexterity to make it impossible to perform effective searches and self rescue procedures such as weight-belt ditching and entanglement management, and can make victim handling a challenge.
Dexterity can also be lost when gloves are very thick or when they constructed as mittens or three fingered gloves. Dry gloves with proper insulation offer superior thermal protection than wet gloves, which allows the use of five fingered dry gloves even in cold water. Dry gloves come either lined or unlined. Fleece lined gloves are comfortable and warm but take a long time to dry should they flood. Unlined gloves allow the wearer to change liners between dives and wear the appropriate thickness liner for the water temperature. Kevlar liners or over-gloves can be used if searches are conducted in areas with sharp debris.
Boots: Attached hard sole boots are preferred over attached latex booties that require the donning of an over-boot. The latter system takes longer to don and requires the drying of these separate boots before they can be stored in service. Attached EPDM rubber boots are simply towel-dried. The disadvantage of attached boots is that they are less accommodating when several wearers with different size feet share a suit. The latex bootie system allows each wearer to have their own pair of over-boots. Attached boots are required for contaminated water diving. Some boots have a small protruding lip off the Achilles’ heel to decrease the chance of a fin strap from slipping off, which is a nice feature.
Other features: Sometimes a department chooses one suit over another based on cost. This is rarely a good idea for safety reasons and because sometimes there are hidden costs. Questions to ask include does the suit come with a good maintenance and repair kit that can cause upwards of $40 or $50 when sold separately. Are suspenders included in the given cost? Suspenders will help prevent unnecessary strain on the suit’s zipper and prevent wrist seals from dragging on the ground. Does the cost include a skull cap for under the hood? What is the suit warranty? What size customizations are offered? Is a carry bag included?
In summary, our experience with thousands of public safety divers around the word has shown that a hazmat tested, EPDM vulcanized rubber suit with a heavy duty back-mounted zipper, heavy duty wrist seals, attached hard sole boots with anti-slip soles, a swivel inflator valve, a domed exhaust valve, a good maintenance and repair kit, and suspenders, best meets the needs of most dive teams.
Surface Ice Rescue Technicians
Drysuits are mandatory for surface ice rescue technicians. The difference between a diving and surface drysuit is that the latter does not have inflator or exhaust valves, they are usually limited to neoprene or some type of nylon or bilaminate shell suit, they do not have true neck seals, and they are usually less costly than diving drysuits. Diving drysuits can be worn for surface ice operations but keep in mind that unless they are constructed of material that is buoyant enough to keep a flooded suit wearer on the surface, then a PFD must be worn over the suit. A second consideration is that diving drysuit inflator valves are located on the chest, so they could become damaged as rescuers work prone on the ice. An advantage of using diving drysuits is that they generally offer the wearer a far greater ability to move efficiently and effectively in the water. Surface ice rescue drysuits were not designed for swimming and should not be used for such.
The water operation community is lead by a group of self-proclaimed experts who do not have any mandatory national standards or qualifications to be held to. Some of these experts design water operation equipment that too often reflects a lack of common sense and a poor understanding of what happens in actual water operations. Exposure suits manufactured for surface ice rescue technicians clearly demonstrate this problem.
Let’s look at some points that are apparently not as obvious as one would think. If a team is called to perform an actual ice rescue, then that tells the team that the ice was too thin to support the victim(s). We are then given a choice of who to put on the ice as rescue technicians – thin, lightweight, fast rescuers, or large, heavy, and possibly not fast rescuers? Hmmm, that will take some thought wont it. Who should we keep on shore to pull lines which can take quite a lot of strength if there are few responders – thin, smaller people, or larger folks? Hmmm. Ah, the answer must be to put the larger people on the ice because that is who most surface ice rescue suits are designed for. There are three main ice rescue suit manufacturers in the U.S., and two of the three make suits in one or two sizes, namely large and huge.
When we put physically fit, lightweight, thin rescuers in these large suits they can be rendered useless by the suits. Feet come out of boots when kicking, hands come out of gloves because sleeves are too long, suits flood, and airways are obstructed as the hoods come up to their eyeballs. One manufacturer who thought this through is Bayleysuit™ who offers suits in small and medium sizes, in addition to large and huge. Bravo Bayleysuit.
Bayleysuit™ also did not make the airway obstruction error that other manufacturers have made. The first surface ice rescue suits were person-overboard suits, affectionately called “Gumbie suits” because of the foot shape. These suits were designed to keep people alive in rough, cold water as they waited for help to arrive, and had face flaps to protect the mouth and nose from waves and spray. These people lay there floating in the water, doing their best not to exert themselves. Does this sound like what ice rescue technicians do? No.
We wonder if manufacturers who include zippers or face flaps that completely cover the wearer’s mouth and nose with rubber or other nonporous material have ever attempted to cross 300 feet of realistically thin ice that breaks underneath them every so often. And have they done this under the stress of reaching drowning victim(s) as quickly as possible? The answer has to be no, because if they did they would realize that they would be quickly ripping off that face flap or yanking down that zipper to avoid going into respiratory distress. Proper procedures keep ice rescue technician airways dry. Face flaps serve to prevent technicians from getting the air that they need to do the job safely. They also serve to make it difficult or impossible to use voice or whistle communication to the victim or shore personnel. So what do we do about this? Write and call manufacturers and tell them what you want. Take a proactive approach, after all it is your safety that is at stake.
Features to look for in surface ice rescue suits include:
* Come in sizes to fit smaller rescuers.
* Avoid zippers or face flaps that cover the wearer’s mouth and nose. Face flaps can be cut back. Zippers that come up too high are more of a problem.
* Built in dry gloves, hood, and hard sole, nonskid boots.
* Velcro wrist straps are useful to keep hands in suit gloves if the suit sleeves are too long for the wearer.
* If the suit has a built in chest harness, make sure it is not secured only by a flap of neoprene sewn directly into the suit, and that it can be adjusted for the wearer’s size. If neither is the case then we recommend removing the built in harness and donning a well made water operation harness over the suit.
* Look for good seams, especially in the crotch area, to decrease the chance of cold water leaking into the suit.
* Mounted hood lights are a good idea for night time or low visibility operations.
* Five fingered gloves require less training and practice than do three fingered mittens.
* Built in or attached wrist ice awls can be very useful.
* Nylon shell suits with closed cell foam liners provide better protection from cold, and provide more mobility and comfort when worn by surface personnel on boats and shore than do neoprene suits.
There are two types of surface ice rescue suits on the market today – neoprene and nylon shell suits. Full thickness neoprene suits have intrinsic buoyancy while some of the other suits require a PFD to be worn. Neoprene ice suits tend to cost less but may not be as comfortable, and take longer to dry. Nylon shell suits can come with closed cell foam liners to provide warmth and buoyancy. These suits dry much faster than neoprene suits, and easier to repair in the field. Their liners can be removed allowing for easier cleaning. The shell suit is better suited to a larger variety of year round water operations. Mustang™ makes the most popular shell suit called the Ice Commander.
No matter what type of ice rescue suit is used, undergarments should be capable of keeping wearer’s warm even when wet. We recommend storing fleece socks and glove liners in the suit storage bag. Avoid wearing cotton.
Moving Water Operations
Increased water speed results in greater convective heat loss. Water that would normally seem warm when still, can quickly incapacitate someone when its speed picks up. NFPA Document 1670 defines swift water as anything moving at or faster than 1 knot.11 Ice rescue suits are not designed for, and should not be used in, swiftwater. Swiftwater technicians require suits that allow for unrestricted swimming skills should technicians end up in the water. Also, because ice rescue suits do not have true neck seals they can easily flood in swift water, further incapacitating rescuers.
Shell drysuits, with true neck seals, helmets and swiftwater PFD’s are usually the PPPE of choice. Hard sole built in boots may not be the best choice because they may not allow wearers to kick effectively.
Surf operations pose the problem of rescuers who need to be able to get under waves for their own survival. Surf technicians may also need to surface dive to recover a drowned victim. This means they cannot wear exposure suits that are too positively buoyant to prevent voluntary submersion. They also need a suit that affords very strong swimming skills, hence restrictive suits are not an option.
Firefighters would not be allowed in burning buildings without the right exposure suit and law enforcement would not be allowed to engage in a gun fight without proper body armor. Likewise, water operation personnel should be kept away from, and out of, water without having on PPPE. Do your research prior to making purchases. Do not take manufacturer’s or even “expert’s” words as gospel. Ask questions and use logic. When possible get training first to gain hands-on experience with a variety of suits prior to making purchases. And never forget that there is only one mission you have to complete every time – go home without being sick or injured.
We look forward to your comments and questions, firstname.lastname@example.org, (845) 331-3383.
Drysuits by Hendrick & Zaferes, (free 5 page, full color information booklet)
Diving Medicine Eds Bove & Fefferson, 1990, W.B. Saunders, PA, 333 pages
Drysuit Diving by Barsky, Long, & Stinton, 1992, Hammerhead Press, CA, 184 pages
Surface Ice Rescue by Hendrick & Zaferes, 1999, PennWell Publishing, Tulsa, 240 pages
Public Safety Diving by Hendrick, Zaferes, & Nelson, 2000, PennWell Publishing, Tulsa, 340 pages
Ice Diving Operations, by Hendrick & Zaferes, 2003, PennWell Publishing, Tulsa, 454 pages
Swiftwater Rescue by Slim Ray, 1997, CFS Press, NC -_ pages
Whitewater Rescue Manual by Walbridge & Sundmacher, 1995, McGRaw-Hill, OH, 198 pages.
Rapid Drysuit Dressing and Flooding of a Drysuit Video, Lifeguard Systems and Delfin Productions.
Surface Ice Rescue, Lifeguard Systems and Delfin Productions
Blackwater Contingency, Lifeguard Systems and Smokey Roberts Productions
Swept Away, A guide to water operations, Alan Madison Productions
Photo captions. The photos are enroute on a CD
1: Drysuits require both initial training and continued practice. Divers are asked to practice disconnecting their inflator valve before or after every dive to be ready for self-inflation problems. Notice that the valve is pointed in the most efficient angle of 45o downwards.
1-1: Laminate shell suits, worn here by both divers and tenders, generally cost less than EPDM vulcanized rubber suits, but they do not offer the same protection or advantages of the rubber suit.
2: PPPE also included ice cleats for surface personnel to help prevent falls and accidental immersion. These ice stabilizers can be worn over any type of exposure suit boot.
2-3: Although decades of ice dives have worn wetsuits, increases in safety standards and new knowledge about cold stress make drysuits a far safer option. Wetsuit divers require shelters particularly after the suits are wet. (Winnipeg, PD, Canada).
3: A shore operations person wears a float coat that provides warm, waterproofing, and buoyancy (left). The in-water tender wearing a neoprene ice rescue suit with an added water operation harness (middle), checks his diver who wears an EPDM vulcanized rubber drysuit with a latex dry hood. The safety officer in the background wears street clothes with a vest PFD. (Ticonderoga FD, NY)
4-5: Diving drysuits have inflator valves that can malfunction in a free-flow position. Divers therefore must be trained how to manage accidental suit inflation problems as part of their drysuit certification traning.
5: These rescuers are fine in thin wetsuits as they learn how to rapidly enter and exit small boats that will eventually be deployed in the ocean. (North Myrtle Beach Rescue Squad, SC)
5-16: Firefighter Nomex hoods make excellent hood undergarments.
5-18: A diver wears a full thickness diving drysuit while her tender wears a full flotation suit for warmth, waterproofing, and buoyancy protection. Neoprene drysuits are not acceptable for contaminated water diving, take many hours to dry and require divers to wear more lead, but they do offer intrinsic warmth and buoyancy.
5-19: When it comes to drysuits, you typically get what you pay for. Zippers are the most expensive component of drysuits. The fewer teeth per inch, the better the zipper.
5-20: A simple homemade neck ring tube can be used to pull the neck seal away from a 90-percent ready diver’s neck for comfort while waiting on land.
5-21: If only one set of undergarments can be purchased, and the team has cold winters, then artic weight undergarments are recommended. The team can use inexpensive fleece sweatpants and sweatshirts during warmer months. (Malaysia Airborne Fire & Rescue)
5-22: Authors maintaining a diving drysuit back mounted, heavy duty zipper with paraffin wax. Back mounted zippers will last longer than front mounted zippers, and allow for a more form fitting suit.
5-37a: If surface personnel do wear turnout gear near the water, they should be take a drownproofing turnout gear certification course. (Stony Point FD, NY)
6: A 5-7 mm two piece wetsuit with a hood, gloves, and boots is only acceptable for clean water that is warmer than 50oF. (Long Ridge FD, CT)
6-18: A debate in the NFPA standards ensued about whether or not turnout gear should be allowed near the water. In reality, turnout gear offers excellent thermal and waterproofing protection in cold, wet climates. If PFD’s are worn near the water they must be used in conjunction with PFD’s that have been tested for having enough buoyancy to hold up an immersed turnout gear wearer. Turnout gear should not be worn if there is a medium to high risk that the person will end up immersed, and if they are near swiftwater. (Anchorge FD, Alaska)
7-12: Surface personnel hands must have proper PPPE. In cold climates thick wool mittens keep hands warm even when the mittens are soaking wet and frozen. They are very inexpensive, allowing the purchase of an inner fleece or wool five-finger liner that should also be worn for when the mittens are removed to perform a task requiring fine mobile skills.
8: The faster the water moves, the more heat we lose by convection. All swiftwater personnel need thermal protection that ideally involves a drysuit. (Ulster Co. Sheriff’s Office)
14-10: Author demonstrating the use of a full length 3 mm neoprene wetsuit in warm (80oF), clean water. We lose heat at the same rate in 80oF as we do in 42oF air so some type of thermal protection should be worn in even those ideal conditions.
CRW-0032: Shell drysuits (left) can be used by shore personnel more readily than can neoprene drysuits and are generally more adaptable to different types of water operations. (CT Fire Teams)
IMG-0027: The Mustang Ice Commander™ has become a popular lined, nylon shell ice suit (left), gaining popularity over neoprene suits (right). It offers greater thermal protection and mobility if the suit fits the wearer. Note that the rescuer stays to the side of the victim to maintain an open airway. If the rescuer stays behind the victim, the victim could become suffocated by snow or water before the rescuer notices this.
IMG-0042: Unfortunately the Ice Commander™ has both a zipper and a flap that obstructs the airway of many wearers, and does not come in sizes to fit smaller technicians.
1 Diving Medicine Eds Bove & Fefferson, 1990, W.B. Saunders, PA, 333 pages
2 A term and position created by Hendrick for a second contingency diver who is at least 90 percent ready to replace a backup diver who for whatever reason is unable to successfully aid a needy primary diver.
3 Keatinge, WR. The effect of work and clothing on the maintenance of the body temperature in water. Quart J Exper Phsiol 1961; 46: p69-82
4 Strauss M., Vaughan W. Jr. Effects on core temperatures of suited divers exposed to 6o centigrated water for 4 and 6 hour durations. Undersea Biomed Res 1978. 5(Suppl), p 31.
5 Vulcanized suits no longer have seams. Two pieces of rubber are baked together so they become one piece of rubber.
6 See “Flooding of a Drysuit” video, by Hendrick, Lifeguard Systems & Delfin Productions
7 DiGiglio, V. Diving in Contaminated Water, just how safe are you? SORTIE vol 1, issue 3, 1999 p
8 available for free from Trellerborg Viking, 800-344-4458
9 These can be obtained from Divers Cover, Essex CT, (860) 767-1960
10 Marcus P, Richards S. Effect of clothing insulation beneath immersion coverall on the rate of body cooling in cold water. Aviat Space Environ Med 1978. 49, p480-483.
11 1 knot is 100 feet per minute. This can be calculated by timing a floating object for 30 seconds or a minute. For example, if it travels 100 feet in thirty seconds then it moved at a rate of 2 knots.
12 All available from Lifeguard Systems, www.teamlgs.com, (845) 331-3383