When you are first learning how to dive. You learn basic skills in the pool before you move to open water. One of the most basic is clearing your mask. There are a couple of reasons you will have to clear your mask. It isn’t sitting right on our face, and it is leaking a little. You are diving with a group of people, and you get kicked in the face, and your mask gets knocked off. This is a skill you should always practice, especially if you have not dove in a long time. No matter how often you dive being good at the basic skills will always pay off.

This is one of the most basic skills to have, but it is also one of the most important. Let’s say you are doing a 3-hour night dive. About 15mins into it your mask starts leaking. You have to clear it every couple minutes. So you decide to change out your mask. This could be a quick thing, or if you have never practiced this, it isn’t going to help at all.

Leaking mask 

After you have inhaled slightly press the top part of your mask to your forehead while blowing slowly through your nose. Tilt your head back slightly looking up while exhaling through your nose. Start to exhale thru your nose slowly. Watch for bubbles if you close to your target. The water will slowly start to leave. You don’t have to do this fast.

Flooded mask

This is just as easy as clearing a partially flooded mask. Let say you are diving in a group and someone kicks you in the face knocking your mask off. First put your mask back on, make sure that you have a good seal and there isn’t anything in its way, like part of your dive hood. Then using the same method above to clear it. Take your time. If you go to fast you will push out more air then water. So go slow and don’t waste your air. If you are really deep when you do this, there will be more pressure, making it a little harder to push the water out. Sometimes it is better to leave the mask strap off and just let the water pressure and your hand hold the mask to your face. Once you have some air in your mask then you should put your mask strap on.

If you are only able to dive a couple of times a year. Then you need to get in the water and practice your basic skills, and this is one that will help a lot. There is nothing worse than being on a night dive, and your mask won’t stop leaking, and you can’t see anything. The best way to perfect this skill is to practice it over and over again in a controlled environment like a swimming pool. The primary keys for being able to clear a flooded mask is to relax. This is the reason you had to do all those flutter kicks on the side of the pool with your mask full of water. Lastly, if you have to do a 3-hour dive and you go thru all these steps, and nothing works, well you at least get a good story out of it.

When conducting combat swimmer operations you will need to have a certain amount of gear on you. This gear will depend on a of couple things. First what you will be doing during the dive, second what you will be doing at the end of the dive. If you are just doing a straight up dive and never leaving the water you can get away with just a gun belt with maybe a couple extra pouches for an extra mask, mask strap or fin straps. If you plan on conducting a ship attack or a raid, you will need more then just a pistol belt. This will be up to the diver and the mission requirements.

Gear Common to all

Items to have on you at all times.

– Gun Belt

– Pistol Holster

– Pistol Mag Pouch

– Water pouch and bottle.

– Radio pouch

– E and E kit

– First aid kit

– Extra mask/ mask strap/ fin strap

– Knife

– Signaling device, strobe/ flares

Gun Belt

There is a lot of them out there right now. There are many things you need to think of when setting it up. You need it to be able to easily expand the belt for the type of thermal protection you will be wearing, IE wetsuit /drysuit thickness.  You need to always have your pistol holster and mag pouches in the same place for muscle memory. Other things to think of are, will you be climbing? If so can the belt be used as a harness by adding leg loops or can it be put over a climbing harness? Can you swim with it on without it rubbing the hell out of your legs? Items like the S+S Precision gear retention track are a great way to move items around with little effort. Lastly a good set of suspender’s will help keep your belt in place and stop it from spinning as you swim.

Pistol Holster– One of the things you need to look at for this is, where you want it to sit, if you want it on your thigh, on your hip or a spot in the middle. If you have it on your thigh you need to make sure it does not move around as you are swimming. It also needs to be able to be easily moved if you have to adjust your belt for the think ness of your wetsuit. It also needs to be able to lock your pistol in so it will not fall out; a bungee is a good item for it to have to lock the pistol in but that can also get stuff on something. Should it have a flap cover to protect the gun a little from small things in the water? With all this stuff it should be able to drain water fast.

Mag pouch –They need to be able to keep your magazines in place when you are diving and be able to get to them out fast when needed. Keeping them free of items in the water and be able to drain water fast. This goes for everything you carry anything it. A good mag pouch is great for carrying an extra mask.

Water Pouch- Be able to carry the water bottle you use. A Nalgene bottle is a great bottle to use, as it’s easy to fill in the field. It also doesn’t take up as much room on a belt.  Typical tactical Nalgene bottle pouches have a mess bottle that drains water fast. Depending on if you have to carry something on your back or not you can also use a Camelbak on long dives when it is hot, it’s nice to drink something other then seawater when your legs start to cramp up.

Radio pouch– as radios advance it means that the people at the TOC want to know more and more what you are doing and when you are doing it. So that means that you might have to take a small radio with you to maintain comms, you might have to take along a survival radio. They can be one of the same but you might have to carry two. As one is none and two is well two is twice as much to carry.

E and E kit -Your E and E/R kit can just be a candy bar and some money to pay some people off or it might be more extensive, like having way to purify water, start a fire and kill a bear. No matter what you have, it needs to be waterproof and negatively buoyant as will everything on this list. You can laminate dollar bills in between two 3×5 cards, so it looks like they are just 3×5 cards for write info on. Then if you need the money just rip them open. This way they are hidden and waterproof. Most good kits are small and can be used for about every situation just by adding one or two items depending on what you are doing. If you have to dump all your gear for whatever reason, make sure you have your kit on you separate from everything else.

Extra straps / Masks- It is best to keep an extra mask/ mask strap and an extra fin strap on you. The extra mask should be the same mask that you are diving. You can put an extra pouch on your dive rig straps and put the mask in there. You can also switch your mask strap out to one of the newer comfort straps. They are made of the same martial that ski goggle straps are made of. As for an extra fin strap you can keep that in there also. You need to have a plan on how to change your fin strap out. This will depend on how it breaks. If it breaks in the middle on the strap, it’s not as bad as if it rips away from the fin and takes some of the fin with it. Most fins have the ability to replace the rubber strap with a  steel spring version. Cave divers started using screen door springs because they wanted something that was extremely reliable. They almost never break. They have them for Jet Fins, Twin Jet max and also the Seawing Nova’s.

Knife– Knives are very personal, and everyone has the one that they like. The main thing to remember about your knife is have it in a place that you can reach it on a dive. Some people like it on their legs others like it on their waist. Some people have one on the leg and on their chest (again one is none). Keep it sharp and clean.

Signal devices – You can and probably do carry both a strobe and a flare when diving. The Flare is for emergencies and a strobe for overt and covert signaling. Both need to be waterproof and easily accessible if needed. The bad think about a flare is they are a onetime use. So make it count if you are going to use it. Almost all that are geared towards the military can handle a combat swimmer dive. Lastly you can carry a signal mirror. It is 100% waterproof and never needs batteries.

No matter what gear you take on a dive you make sure it is probably maintained. Make sure you prepare for the conditions and environment you will be in and adapt you gear and E+E kit for it.

Buoyancy is key to a lot of things. It helps make the dive easier in a lot of ways. When using a closed circuit rig (CCR) it keeps you from rocketing to the surface, it prevents you from dropping to the bottom when you stop to fix your gear or “Dräger” talk/ yelling at your dive buddy.

There are two keys to buoyancy: balance and breathing

The two significant factors in achieving neutral buoyancy.

• 1st Wear the right amount of weight for the dive. This will differ depending on the thickness of your wetsuit/ dry suit and gear you are wearing.

• 2nd Breathing slowly and evenly and not having too much air in your breathing bag. If diving a CCR

What is the best way to maintain proper buoyancy?

Pre-dive preparation. Buoyancy control begins, with the pre-dive preparation. As you pick what to wear for a dive. Double-check to make sure nothing has changed that could affect buoyancy. A new wetsuit is more buoyant than an older one and will need more weight. A new suit has more inherent buoyancy at first because diving, especially deep diving simply bursts its bubbles. New gear; compare the old version to the new. Gear is always being updated with new buckles or martial so when you switch from old to new make sure you know what the buoyancy is of the new stuff. So when you go to the new magazine pouch make sure you know how it is in the water. Check the weights on a scale; often there is variation between claimed and actual weight. If diving open circuit, are you using a new cylinder? Some cylinders are negatively buoyant when full and simply less negative when empty; others sink first and float later.

Do a buoyancy check. Here is the best way to do a proper buoyancy check. With your lungs half-full, you should float at eye level with no air in your BC. If you are diving open circuit, remember the average cylinder loses about 5 pounds as it empties. So you might have to add about 5 pounds to your weight if you have done your buoyancy check with a full one.

Keep a log

Keeping a log of what gear you have wore, what the temperature was and the type of water (salt/fresh /brackish). What equipment you used, how much lead you carried, how much your body weighs and whether you seemed too heavy or light.  Knowing the weight of the gear that you used on the dive will help. Make sure you understand that if you are going to remove something during the dive you need to account for that on the return trip home. If you plan ahead by recording in training what you used it will help when you have to do it the next time.

Saltwater VS Freshwater.

If most of your diving is done in the ocean, then ballast calculations should be done in the ocean. Jumping in the pool to check your balance will get you close, but it won’t be 100% correct. If you switch back and forth, you’ll need to adjust your ballast. Be prepared to add anywhere from 4 to 7 pounds going from fresh to saltwater.

Buoyancy, Trim, Position, and Breathing

The secret is buoyancy control, begins with fine-tuning your weighting. How much lead you put into your pouches or have on your weight belt. If you are carrying just the right amount of weight, you will only have to put a little air in your BC. That means less drag and more efficient finning. Less BC inflation also means less buoyancy shift with depth, so you’ll have to make fewer adjustments. There are many tricks, but buoyancy control is the fundamental skill. Precise control of your buoyancy is what enables you to hover motionless and fin through the water, at any depth, without using your hands at all or stirring up mud or silt from the bottom. In addition to using the right amount of weight, make sure you are correctly balanced to optimize your position under water. Keeping a more horizontal position makes you more hydrodynamic. Distribute the weight as uniformly as possible from side to side; you should never notice that you put on more weight on one side while diving. You must also consider the weight of your dive gear and any other additional gear you might be wearing. I.E gun belt or special gear. Make sure it is balanced on your body and it doesn’t shift when you are diving. The lowering you wear your dive rig can cause a tendency to push the diver forward (upside down) in the water, so the placement of weight towards the back can help reverse this position, especially on the surface. While carrying weight in the pockets on the back of the vest or taped to you rebreather can help with the adjustment. Lastly, any dive weight you put on should be easy to remove in an emergency.

The factors that affect your buoyancy besides ballast weight are BC inflation, your trim, exposure suit, depth and breathing control. Your ballast weight and your trim are the only two factors that, once you’ve selected them, stay put. Ballast is the amount of weight it takes to keep you neutral in the water. Trim is about the position of your body weight relative to the position of your weight. Sometime when diving a rebreather you can tape lead washers on it to help with your trip.

There is one more thing to understand that will help with your buoyancy. It is controlling your breathing. Make sure you maintain proper breathing. Take long, relaxed breaths this will allow you to maintain control over your buoyancy.

To determine the amount of weight you need, you take your body weight, the diving suit you are going to use, the weight of your equipment and the environment you are diving in salt or fresh water. You can use about 10 percent of your body weight,  is a good starting point for a full  5 mm or more and for a 3 mm suit, use 5 percent of your body weight.

Dry suits and thick neoprene suits require more ballast to counteract the increased buoyancy of those suits in comparison with the thinnest. Body composition (the muscular density, for example) will also influence the necessary weight.

Remember to calculate for everything you are going to do and wear on your dive. If you are doing a long dive and plan to leave or remove something half way thru your dive. Say doing a ship attack, and you are taking limpets off. Plan for the whole dive. To check your buoyancy get into water deep enough to stay in an upright position, without treading and releasing all air from the vest. Inhale, in a normally, the surface of the water must be at the level of your eyes. When you exhale, you should sink until water covers your head and inhale again, you should emerge once again until the level of the eyes. Adjust your weight in small increments about 1 pound at a time.

Once you get your ballast weight and trim dialed in, you will be ahead of about 75% of all divers toward perfect buoyancy control. Now you can fine-tune your BC inflation to compensate for the very predictable changes due to breathing down your tank and changing depth and use only breath control to drop gently down to that cleaner shrimp, hover inches above it as long as you want and lift away from it harmlessly.

Lastly, there are advanced classes that you can take that focus on advanced skills like this. This may seem like a lot of work, but it will help make diving a lot better and make you more efficient at it.

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As far back as 3000 B.C.E, (5000 years) people were going after natural sponges off the coast of Crete and breathing through the world’s first snorkel tube that they made from hollow reeds. Aristotle, the Greek philosopher, recalled instances of divers breathing through a device similar to the trunk of an elephant.

In later years, the Assyrians developed an alternative snorkel device. They filled animal skins with air to breathe from when they were under water. Aristotle wrote about divers who used a tube that led from the surface to the divers below.  The consummate Renaissance Man, Leonardo Da Vinci had many designs that he called diving or underwater apparatuses. He designed a self-contained dive suit and even sketched diving gloves with webbed fingers. Technically, they could be considered the fist fins.

The development of the diving bell which contained air bubbles for divers to inhale while underwater was overseen by Alexander the Great.

• 900 B.C.E- Assyrian divers used animal skins filled with air in order to lengthen the time they could spend below the surface of the water.

• 333 B.C.E Alexander the Great encourages divers to develop and use the first diving bell — a large bell-shaped object that trapped air in the top of the bell (and a person) to submerge and maintain the ability to breathe.

• 1538- Greeks in Spain (Toledo) submerge themselves in large diving bell-like contraption to the bottom of the Tagus River only to emerge later with dry clothes and a still burning candle.

The same concept allows modern-day snorkelers to breathe air from the surface with their face submerged. Modern rubber and plastics make equipment durable and comfortable while offering maximum safety. With the advances in rubber and plastic composite materials, snorkels have significantly improved their function and use. The most popular snorkels is the J-shaped plastic tubes connected by a flexible strap or clip assembly to the diver’s mask.

Snorkels for diving

The snorkel makes it possible to breathe safely on the surface without using the air in your tanks. When choosing a snorkel, think first what you want to use it for and how you will use it the most. The diameter is important because it minimizes your effort while using it. Most snorkels are brightly colored so dive boats can easily spot them and more importantly you.

Free-diving Snorkels

Free-diving snorkels are often the simplest models. They are made without a complex purging system and without valves to limit breathing noise, those snorkels are also shorter to easily expel water from the tube and are easily tuck away. They usually have a slightly larger diameter to properly ventilate between two dive immersions. They are one of the best for Combat swimmer to use, as they are small and can be packed away easily and mostly come in dark colors.

Types of Snorkels

There are four common types of snorkels and each has their advantages and disadvantages.

Classic

The classic snorkel, also called a J-style snorkel, is a plastic tube with a mouthpiece attached. This snorkel is usually slightly bent, but it can also be made to fit a more specific shape. The SCUBAPRO Apnea snorkel can be rolled up and easily stored in a pocket or attached to the sides or bottom of a Rebreather. This is the one best suited for combat swimmer operations.

Flexible Snorkel

The flexible snorkel has a purge valve. This snorkel has a flexible portion and a rigid portion, as well as a one-way valve located at the bottom that makes it easier to expel any water that may get into the snorkel. The added flexibility allows divers to fit the snorkel better around their masks and faces. The purge valve at the bottom of the mouthpiece helps ensure uninterrupted breathing as it flushes water out every time you exhale.

Semi-Dry

The semi-dry snorkel is a mix of a classic and dry snorkel. The top features a splashguard, and sometimes even a flexible tube and a purge valve. The splashguard at the top helps to prevent splashes or sprays of water from easily entering the tube. It doesn’t prevent all the water from entering, especially if you fully submerge yourself underwater or if water covers the top like in a high wave.

Dry

The dry snorkel has a valve at the top of the snorkel. The valve blocks water and air when the snorkel is submerged—and a purge valve at the bottom. They are great for snorkeling on the surface and occasionally dive without having to worry about constantly clearing water out of the tube. When used for diving, the advantage is that divers don’t have to clear them of water when they reach the surface.

As with semi-dry snorkels, the one-way purge valve at the bottom allows the user to easily flush water out with a few quick exhalations. While the dry snorkel is more convenient and efficient to use, it can also has its drawbacks. The valve at the top of the snorkel can sometimes become blocked. The dry snorkel may also be more buoyant underwater.

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