Advanced Adventure Diver for eLearning is Here

You have asked for it and we were listening.  As one of SDI’s most talked about specialty programs, Advanced Adventure Diver is available on our eLearning platform.

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The SDI Advanced Adventure Diver course will give you an overview of five (5) selected SDI specialties. Two of the specialties are SDI Deep Diver and Navigation Diver, which are the foundation of continuing diver education. The remaining specialties include:

  • Advanced Buoyancy Control
  • Altitude, Boat
  • Computer Nitrox
  • Drift
  • Marine Ecosystem Awareness
  • Many More!

This course is intended as an introduction to each of the five (5) specialties and not for complete comprehension of the chosen specialty. One (1) dive from each of the chosen specialties may apply towards a complete specialty certification.

Contact your local area SDI representative and order your Advanced Adventure codes TODAY!

Contact SDI TDI and ERDI
If you would like more information, please contact:
Tel: 888.778.9073 | 207.729.4201

Underwater Journal, Issue 26 is Here

UWJ Issue 26 is ready for download. If you have not subscribed, simply sign in and create an account (takes just a few minutes and it’s FREE).

This issue of Underwater Journal dives into some great features including:

  • Two giant species of Manta Rays – A researcher studying giant mantas finds that one of the oceans’ most enigmatic symbols has in fact a secret twin; proving it took six years of hard work, much of it accomplished with limited logistical and financial support, in an environment that offered little understanding or sympathy for her cause.
  • Bonaire and why it is still a divers’ paradise – It’s an infatuation that has spanned nearly three decades, and continues to grow. Familiarity has not brought complacency; instead, there always seems to be some new wrinkle in the relationship that keeps things fresh and exciting.
  • United Caribbean &Sea Emperor – Entertaining a Double Header Wreck Dive on the Broward/Palm Beach County Line
  • Sea Trial: KISS GEM Semi-Closed Rebreather – Exploring the world of gas efficiency through semi-closed rebreather technology.
  • Diving the island of St. Lucia – St. Lucia is the sort of island that travelers to the Caribbean dream about – a small, lush tropical gem that still manages to stay relatively apart from tourism’s more trodden paths.

There’s much more to enjoy and learn, get your FREE magazine today. Don’t forget, UWJ is iPad compatible to download and save in iBooks.

This is YOUR MAGAZINE with lots of benefits. We appreciate your support and encouragement! Enjoy, and please let us know what you think.

Underwater Journal is the official publication of SDI/TDI/ERDI

Download issue 26 here: download.

Contact SDI TDI and ERDI

If you would like more information please contact:

Tel: 888.778.9073  |  207.729.4201

Rescue Diver Course: Recognition Before the Dive

Scuba diving is intended to be a fun activity that allows you to experience the underwater world as its residents do, living among the sea critters, large and small.  The equipment that divers use allows for the adaptation of the ocean realm to our body.  If breathing out of a hose and having to wear a mask to see clearly feels weird; it is because it is weird.  Our bodies are not designed to breathe and see underwater and therefore, we have to adapt not only physically, but mentally as well.

It is important to recognize how you feel before a dive, because this will certainly be a factor in the level of enjoyment that you may experience during your dive.  It is perfectly normal to feel some nerves or to experience stress before getting into the water.  After all, assembling your equipment and getting kitted up is noted as being one of the most stressful time periods, as the diver is about to embark on an adventure into another world.

Having the jitters before a dive may also be a result of a degree of confidence. If you are a newly-certified diver about to have your 10th dive after certification, a case of the jitters is quite normal and frankly, if you weren’t, it wouldn’t be normal. Is this dive going to be difficult?  Am I prepared for this type of dive?  Am I properly trained?  Do I have the appropriate equipment for this dive?  These are all appropriate thoughts to be having and show that your mind is where it needs to be.

As you gain experience you’ll notice an increase in confidence in your skills, an increase in your ability to recognize right and wrong while still maintaining a normal level of nervousness. What you don’t want is to become so comfortable that complacency overrides your nervousness. Anxiety is perfectly normal, and can even be healthy as an indicator of your mental state of mind.   It is usually created by a mix of excitement…and who would not be excited prior to a dive?

It is important to be able to recognize panic or stress before a dive.  Going into a dive with the wrong frame of mind can lead to a dangerous experience.  It is always better to abort a dive and regroup, than to jump into a dive that may lead to a panic situation.  There are many reasons for levels of anxiety to reach dangerous levels including, poor gas management, lack of knowledge of the dive site, adverse weather conditions such as cold climates, surge, and rough water surface.

A large part of the diving instructor’s role, in fact, is in creating a comfort level that induces eagerness rather than anxiety and confidence rather than bravado in the student.  Still, many novice divers will enter the water with the thought that they will always be waging a life-or-death battle with hypothermia, malicious currents and insatiable predators. Stress is a predictable consequence of this train of thought.

Recognizing the signs of stress

  • Withdrawal
  • Constant talking
  • Inappropriate or ‘black’ humor
  • Hyperactivity
  • Gear fumbling
  • Moodiness

SDI’s Rescue Diver course will help you understand prevention of some of the leading causes of accidents relating stress and psychological factors including the panic syndrome in self.  It is important for divers to understand how to read signs in their own behavior, as well as that of their fellow divers.  Learn more about physical conditioning, equipment management, diver assists, surface and underwater rescues and diver first aid.  The SDI Rescue Diver class is not only designed to offer you knowledge in how to prevent unfortunate diving incidents from occurring, but how to properly deal with them in the event that they do occur.  You will find that divers will be much more comfortable after having the SDI Rescue certification and it is a fun class to take with your dive buddy, before heading off for a trip, be it a spouse, parent or offspring or your diving friends.

For more information on this topic, sign up for SDI’s Rescue Diver Course today at your local SDI Dealer.

Contact SDI TDI and ERDI

If you would like more information, please contact:


Tel: 888.778.9073  |  207.729.4201



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The Self-Reliant Diver (Rescue Diving)

The Self-Reliant Diver

Our view of scuba diving has probably changed somewhat from the time of our initial training program to the time when we’re ready to undertake Rescue Diver training. We’ve broadened our range of experience through repeated diving activities in, most probably, increasingly wider types of diving environments. We’ve learned new skills, ‘tricks of the trade’, amassed more knowledge, and dived with several, if not many, buddies. We’ve gained experience and improved our judgment, the two indispensable keys to safer, more enjoyable diving. Most of our beginner’s jitters and reservations have been conquered and we feel that we’re becoming the kind of diver we always wanted to be; reliable, capable and self-reliant. Self-reliant?

Self-reliance is as important an attribute as a diver can possess. If we haven’t given this much thought before, this would be a good time to do so. Admittedly, the ability to look after all our problems underwater without assistance from a buddy may not be the first thing that would occur to us when we consider what we need to dive safely. After all, the point was made time and time again in our training programs that we always dive with a buddy. This is a good rule that helps us increase our enjoyment of diving, brings people together in a shared social setting and gives us the confidence to explore new areas. So, where does self-reliance come in?

Imagine for a moment that you and your buddy are nearing the end of what has been a truly memorable dive: the walls were vertical and blanketed in the kinds of marine life seen only in the magazines, the warm water was clear enough to see from here to next week, and the prospect of relating the dive to envious friends back home beckons. Then you realize that your buddy is gone. Which of you is responsible for this: you, because you were daydreaming, or your buddy, because he stopped to take just one more photograph? Your own air supply is dwindling and you suspect that your buddy may have even less. It dawns on you that you’re not even sure where you are; you weren’t paying that much attention on the way back, and your buddy was doing the navigating anyway. What should you do?

Self Reliance

  • Understand your dive equipment
  • Take personal responsibility
  • Develop self awareness skills
  • Become more aware of your underwater surroundings
  • Plan for contingencies
  • Learn to handle your own underwater emergencies

Looking around more carefully, you see bubbles in the distance and swim to your buddy who’s trying hard to tighten a loose weight belt while balancing the camera and the demands of buoyancy control at the same time. With a little help from you, the crisis is quickly resolved and you’re both soon back on the boat again and reliving the highpoints of the dive. Some new lessons have been learned, too. Never again will you leave the navigation entirely in someone else’s hands, and you wish to seek out a buddy who is independently capable of looking after typical underwater problems without causing you moments of anxious concern.

SDI believes that all divers should be trained to be self-sufficient.  This means that each diver accepts the responsibility for his or her own planning, equipment and performance underwater. We are all ultimately responsible for our own safety and conduct on a dive. Any time our problems require assistance from our buddy on a dive, we disrupt the flow of the dive at the least and possibly endanger them at the worst. In fact what we strive to be is the ideal dive buddy; able to plan and lead the dive, capable of looking after most underwater problems, attentive and responsible. We can become better than we are by practicing and refining the basic skills of diving and by developing new skills and knowledge. Many of the new assessment and problem-solving skills that will make you an independently capable diver will be learned in SDI’s Rescue Diver course.  Along with this will come the knowledge that you’ll also become a more valuable dive buddy. We look forward to working with you to help you become a safer diver.

Contact SDI TDI and ERDI

If you would like more information, please contact:


Tel: 888.778.9073  |  207.729.4201



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Air Management and the Importance of Learning Surface Air Consumption Rate (SAC)

Scuba diving has come a long way over the years. In the early days, divers were equipped with the most basic of dive equipment, which included a cylinder with a “J” valve and no SPG. While this early equipment did allow for exploration and some basic safety protocols, there was certainly room for improvement. Along with that basic equipment was the primary knowledge that was passed on to future divers. This knowledge was gained from military and commercial applications and distilled down so it met the needs of recreational divers. Where is this short history lesson going – stressing the importance of air management!

Back to that J-valve, the basic concept was; if the J-valve was in the proper position (which was up) when the diver started the dive, once the cylinder reached a pressure of roughly 34 bar / 500 PSI, the diver would pull a bar that was attached to the J-valve down and get access to the reserve air for their ascent. Let’s just say this was not the perfect system for more than one reason. Another flaw was, it was not common for divers to be taught how to calculate their air consumption. Fast forward to today, and we have all the needed technology and the necessary information is right at our fingertips. There are dive computers that calculate our air consumption, decompression information and even our heart rate; we can’t ask for much more than that! The problem here is, not all divers dive with these types of computers. In fact, some divers don’t dive with any computer. So what is a good back-up system for divers that don’t have computers that calculate air consumption or don’t dive with dive computers? The surface air consumption or SAC rate formula.

The SAC formula helps a diver understand, on an average basis, what their air consumption will be at a given depth. This allows the diver to better plan how long their dive can be, giving two points for dive turn times: no decompression times and available air. The SAC formula is: SAC = (PSI at depth used/time) x 33/(depth+33)). To perform this in metric units, use bar instead of PSI and 10 instead of 33.

An exercise to perform which helps plan air consumption in various conditions such as currents, high workloads etc is to find a site where you can sit in one atmosphere of water (10 metres / 33 feet) and take three samplings of air consumption: resting, moderate workload and high workload. For the resting, using a slate to note your starting air pressure and sit or swim very lightly for 3-5 minutes, then note ending pressure. For the moderate workload exercise follow the same air pressure noting procedures, but this time swim at a moderate pace making sure to stay a depth of 1 atmosphere. For the high workload exercise, find an object such as a rock or wreck (something that will not move and where you will not damage marine life) note your starting pressure and place your hands on the object and try to push it while swimming, after 3-5 minutes note your ending air pressure. After performing these three exercises, you will have a clear picture of air consumption rates for low, medium, and high workloads.

The purpose and importance of incorporating air consumption into your dive plan is that the only reason you are able to stay underwater for a prolonged period of time is the air you have in your cylinder. If you do not know how long your air supply will last, or you are not tracking your air during the dive, you could run out and risk serious injury from a rapid ascent or not having enough air to perform a proper safety stop. In days past running low or out of air was a function of the equipment at the time (no SPG or dive computers) the limited knowledge available to sport divers and scuba equipment that was not built as well as it is today. Those times and reasons are far behind, and now a days there is no excuse for running out of air.

For more in-depth knowledge of dive planning and SAC, go to to learn more and locate an SDI Dive Center near you. With some basic precautionary steps in place your dives can be fun and enjoyable.

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The Value of a Wreck Diving Course


Photo Provided by Bill Downey

Many divers think that wreck diving is the most exciting underwater activity that you can pursue. Whether you are exploring the liberty ships or submarines off the east coast of the U.S., the WWI German fleet off Scapa Flow in Scotland, “wreck alley” off San Diego, or the galleons off the Florida keys, there’s something about shipwrecks that stirs most divers into a frenzy. Perhaps it’s the thought of finding sunken “treasure,” the chance to photograph the guns on a warship, or the beauty of a wreck as it slowly becomes an artificial reef that lures you.

Shipwrecks are bits of history, frozen time capsules of the era they sailed, even on the day the ship went down. To explore a shipwreck is to learn about the past. Once you visit a wreck, you’ll almost always want to know more about it. Or, you may learn about an undiscovered wreck and feel the urge to research it and locate it for diving.

The wreck of the Royal Mail Steamship Rhone is an example of a classic shipwreck and one of the most picturesque wrecks that you can explore. She sank in 1867 in a violent hurricane that ripped through the British Virgin Islands. The huge open end wrenches used to work on her engine are still in place, as are the cannons used to defend her. You can see the crow’s nest, the mast, and many other parts of the engine and ship’s fittings.

As you become involved with shipwreck diving, you’ll undoubtedly want to know why each wreck sank, how it sank, and when it sank. The stories behind wrecks are almost always fascinating to discover!

Additionally, shipwrecks are great places to see marine life, because they provide hiding places and opportunities for both small and large marine creatures. Lobsters can be found inside ship’s cabins, under deck plates, and inside masts and pipes. Barracuda swirl around tropical wrecks. Tiny fish known as “glassy sweepers” school by the thousands inside warm water wrecks around the world. Soft corals wrap their tentacles around the railings of old freighters and spiny oysters grow on any available surface. Yet, the shape of the wreck can still be seen beneath these mantles of living creatures.

For underwater photographers, shipwrecks present an infinite variety of photographic opportunities, whether you want to shoot macro close-ups or wide angle. You can capture images of tiny, colorful starfish living on the hull of a ship, or frame a diver examining a giant ship’s propeller. If you shoot video, your viewers can make a “virtual” dive by watching your explorations on tape or computer.

The experiences, tips, and techniques in SDI’s Wreck Diving Course are the result of many years of diving. This course will cover, in considerable detail, all the elements of diving from both commercial charter vessels and private craft. Everything from how to stow your gear, to applicable local and government regulations will be discussed, along with valuable explanations of methodology and etiquette. And since many sites require divers to deal with currents, we have incorporated special instructions on drift diving practices as well.

You’ll find this text to be a valuable resource on an exciting subject. We’ve enjoyed putting it together and hope you’ll enjoy the wonderful benefits of boat diving and the exploration of wrecks as much as we have. Good diving!

SDI Wreck Diver Course –

SDI Wreck Diver eLearning Course –

TDI Advanced Wreck Diver Course –

Scuba Equipment for Wreck Diving


Photo by Ray Bullion

Probably the first motivation for people to attempt diving was the pursuit of shipwrecks, either for commercial salvage purposes or to recover sunken cargoes that included classic treasure riches. And while there are countless interesting subjects to keep us enthralled underwater, the chance to explore a shipwreck, no matter how small or deteriorated, holds a special spot in the hearts of all divers.

So before jumping into the water to explore that wreck you’ve been dying to see, make sure you have your gear in check. Most all gear for wreck diving can be divided into two categories; i.e., equipment to help you locate a wreck and personal equipment to help increase your safety and enjoyment while wreck diving. The equipment that will help you locate a wreck is not essential unless you are diving from a small boat and attempting to locate a wreck on your own. The personal equipment for wreck diving includes items that will be useful to every diver who explores shipwrecks.

Gear for Locating Shipwrecks

While locating a previously unexplored shipwreck is never easy, modern electronic navigation equipment and surveying devices have made this task much simpler. There are many tools that can help you including charts (paper or electronic), magnetometers, side-scan sonars, fathometers, and metal detectors.

These electronics have dropped enough in price that many of them are within reach of the serious wreck diver. Charter vessels that cater to serious wreck divers may be equipped with some or all of these aids to navigation as well.

Personal Equipment for Wreck Diving

Personal equipment for wreck diving includes items such as high-performance regulators, bail-out systems, dive lights, knives, and other accessories. Although these items are not essential for sport wreck diving, they are highly recommended.

High-Performance Regulators

Since many wrecks are in deep water, some divers consider a high-performance regulator to be essential for wreck diving. The regulator should have a low work of breathing, meaning that it should not take much effort to either inhale or exhale through the regulator. It should also have a rugged, reliable design.

In addition, be sure to select a regulator that can accommodate a sufficient number of low-pressure accessories including, at a minimum, a BC inflator, dry suit, and additional second stage. Additional low pressure ports will allow you to route your hoses wherever the least amount of strain on the hoses will occur.

Bail-Out System

A bail-out system is a completely separate and independent breathing system to provide you with emergency air in the event that you run out of air for any reason. The typical bail-out system for sport diving includes a small scuba cylinder (usually 13 cubic feet/2 litres), a regulator, a submersible pressure gauge, and some type of mounting system to attach the cylinder to your primary air supply.

The use of a bail-out bottle (sometimes referred to as a “pony bottle”) and regulator is much preferred to the use of an octopus rig. This allows you to be completely independent of the need to share air with your dive partner in an emergency.

Dive Light

A dive light is a recommended accessory for wreck diving, even during daytime dives. A light will allow you to look back inside “pockets” under the wreck and will reveal the true colors of the marine life on deeper wrecks.

Dive lights need not to be big to be efficient. There are many excellent smaller lights on the market that are more than adequate for recreational wreck diving.

In selecting a light, look for the following features:

  • Sinking light – to prevent the light from floating away if you need to set it down.
  • Locking switch – to prevent the light from accidentally turning on while it’s in your dive bag.
  • Long burn time with maximum candlepower.
  • Rubber shroud – protects front of light from damage.
  • Lanyard – attaches to your wrist but easily removed in the event of entanglement.

Between dives, be sure to avoid leaving your dive light in the sun, especially if the weather is hot. The temperature inside the sealed case can get extremely warm and cause the o-ring seal to fail, or your batteries to leak, ruining the light.

Be sure to rinse your dive light with fresh water after each diving day and loosen the battery compartment “door” if you won’t be using the light again for awhile. On most lights, the batteries are installed by unscrewing the lens, which also holds the bulb. If you allow the light to sit with the lens screwed down tight, the o-ring may be permanently compressed which could cause your light to leak. When you loosen the lens, if the light is still wet, be sure to set it down so that any water will not run inside the light.

Before you go diving again, remove the lens completely and clean and lubricate the o-ring. Wipe the o-ring with a clean paper towel and clean out the groove where the o-ring sits in the light. Lightly coat the o-ring with a thin film of silicone grease and screw the lens back down until it is snug. The o-ring must be properly installed, or the light will flood.

Dive Knife

Any dive knife used for wreck diving must have a sharp blade to enable you to cut through fishing line, rope, or netting easily. You should have at least one knife and preferably two, especially for diving wrecks that are known to be frequented by fishermen.

Your primary knife should have a large blade that has both a straight blade and a serrated edge. You can mount this knife on the inside of your calf or on your weight belt.

Your back-up knife can be smaller, but it should still have a sharp blade. Many manufacturers make small knives that can easily attach to your buoyancy compensator or a low pressure hose using a special sheath.

One of the trade-offs in selecting a knife is finding a knife that will maintain a sharp edge and that will not rust. Although all dive knives are made of “stainless steel,” there are different types of stainless material and almost all will rust. You can help prolong the life of your blade by taking the time to rinse it with fresh water after each diving day, drying it, ensuring that the sheath is dry, and spraying the blade with a light coat of WD-40® or other anti-corrosion agent. Wipe the blade dry of any excess corrosion inhibitor with a clean cloth or paper towel.

Cutting Devices

Sidecutters, linemen’s pliers, or boater’s scissors are tools designed to cut wire. For a wreck diver, a pair of sidecutters can be an important tool, since many wrecks are strewn with wires and cables. Some fishing nets are also easier to cut with a pair of sidecutters than with a knife.

To prepare your sidecutters for diving, you’ll need to attach a line to them so that you won’t lose them. A three foot length of braided nylon line works well for this purpose. Tie a knot around one of the grips on the sidecutters and wrap the knot generously, and tightly, with waterproof electrical tape. Stretch the tape as you wrap it around the grip and it will adhere better.

Tie a loop in the other end of the nylon line, or connect the line to a brass snap hook that can be connected to a “D” ring on your BC. Some BCs will have rings fastened inside their pockets that can also be used for this purpose. Place the sidecutters in your BC pocket where they will be out of the way until you need them.

Since most sidecutters are made of ordinary steel, they will rust when removed from the water. For this reason, it’s important to remember to remove them promptly from your BC pocket, rinse them well with fresh water, dry them, and spray them with a corrosion inhibitor.

Underwater Slate

A plastic slate can be extremely useful during any dive, but are particularly useful for wreck diving. You can write on the slate with an ordinary lead pencil. There are also plastic pencils (non-mechanical) that have replaceable lead that work quite well underwater.

The slate can help you to communicate with your dive partner, but for wreck exploration, its main function is to help you map the wreck so that you better understand how the site is laid out on the bottom. You can use either a wrist slate or a flat slate, although a flat slate tends to work better for drawing the features of a large or widely scattered wreck.

The more detailed your notes, the easier it will be to map out the wreck so that you know where the artifacts are located and how the wreck is situated. The larger the wreck and the deeper the water, the more time it will take you to see the entire wreck and complete your sketch.

To clean your slate, use a plastic scouring pad with an abrasive cleaner. You can also use an ordinary eraser, but a scouring pad and cleaner are much more effective.

Wreck Reel

Although reels are used primarily for penetration dives inside wrecks or caves, they can also be useful for exploring the exposed portions of a wreck, particularly on a site where the visibility is poor and the wreck is broken up. Learning how to use a reel effectively is not difficult, but it does take a little practice.

Most underwater reels are made of stainless steel, brass, or plastic parts. They are designed to be hand-held, but can be clipped to your BC when not in use. The crank should be large and easily gripped with gloves. The reel must also have a lock to prevent line from feeding out when the reel is not in use.

Most reels are rigged with several hundred feet (60-90 metres) of braided nylon line. You can attach a brass snap hook or other similar type of fastener to the free end of the line so that it is simple to attach the line to the wreck.

Reels should be rinsed with fresh water at the end of each diving day, and any metal parts should be sprayed with a light coating of corrosion inhibiting spray to keep the reel turning smoothly. The line must be replaced whenever it shows signs of wear. If the line breaks while you are underwater, you could find it difficult or impossible to return to your starting point on the bottom.

Marker Buoy

If you are diving a new wreck, and you have just located it for the first time, you may want to use a marker buoy to identify the central portion of the wreck, or other key points, to which you want to return. The buoy can be used to take surface fixes, too, by using either visual line-ups (triangulation) or using electronic navigation instruments, such as GPS.

Buoys for use underwater usually consist of some type of small float, 100 feet (30 metres) or more of braided white nylon line or polypropylene, and a small weight to compensate for the buoyancy of the float. Since polypropylene floats, it tends to work better underwater and the line has less of a tendency to end up in a knotted mass. A brass snap hook may be used to attach the marker buoy to your buoyancy compensator, or depending on the size of the marker, it may fit in your BC pocket.

When you’re finished using the buoy, tightly wind the line back onto it, and rinse it with fresh water. Store the buoy out of the sun to help avoid deterioration.

Up-Line Reel and Float

If you regularly dive wrecks in deep water, far from shore, you may sometimes find yourself in a situation where the boat either drags its anchor off the wreck or the anchor breaks free. In either case, these situations usually arise due to sudden changes in weather.

In a situation where you return to the spot where the anchor was fixed, only to find it gone, there is no substitute for an “up-line reel” and/or a float (buoy). This allows you to make a safety stop without the need to hover in mid-water.

Divers may use a variety of reels underwater to assist them in making safety stops when the boat has pulled off site or if they were unable to return to the anchor underwater, if the boat has dragged anchor or the anchor line has been severed. In situations where there is no strong current, you fasten your line to the wreck and unreel it as you make your ascent to your safety stop. When you are at the appropriate depth for your stop, you inflate the lift bag to mark your position. Once you have completed your stop, you release the line from the wreck, surface, deflate the bag, and signal the boat to pick you up.

The preferred type of line to be used on a reel for this application is manila, which is a natural fiber line that will eventually disintegrate underwater, leaving no trace of its existence. This is preferred over nylon lines, which will last for many years.

If manila is chosen, it must be wetted down and stretched before it is used on a reel. If it is not, there is a good chance it will constrict and knot itself into a ball, making it very difficult to handle.

Whether you’re gearing up to explore a new wreck or to revisit that mysterious ship in the Caribbean, you always want to make sure your dive equipment is in check. Take that extra time to ensure all your gear is rinsed thoroughly, dried and stowed away in a safe environment so that it can be re-used on your next diving adventure. Happy and Safe Diving!

Get Certified for Wreck Diving

SDI Wreck Diver Course –

SDI Wreck Diver eLearning Course –

TDI Advanced Wreck Diver Course –

The Allure of Wreck Diving

By Steve Lewis


Photo Provided by Bill Downey

Wreck diving is, for some of us, the single most fascinating aspect of diving itself. Many of the divers who we look up to and hold as role models admit that the history, mystery and allure of diving shipwrecks is what initially motivated them to take up diving. Wreck diving is why we dive and really is at the very core of what makes divers tick.

I believe that if you were to tell someone that you are going “wreck diving” next weekend, she would immediately think ‘shipwreck,’ and even as divers we tend to use the phrases wreck diving and shipwreck diving interchangeably. However, to be perfectly correct, wrecks include just about anything that used to be on the surface, but which now sits on the bottom, from an old steam train or school bus, to a helicopter! But all that aside, I’d like to concentrate on wrecks that started life floating on the surface of the ocean (or river or lake) rather than sitting quietly on the bottom.

When purists talk about shipwrecks, they divide them into three main categories: artificial reefs (sometimes called intentional wrecks), accidental wrecks, and casualties of war or conflict. All three have their unique appeal and all three require a slightly different approach to be enjoyed to the fullest.

Within each of these categories are sub-categories such as wooden wrecks, steel wrecks, sailing ships, freighters, and navy vessels, with further refinements like schooners, liberty ships, hogbacks, brigs, U-boats, and so on. And the real aficionados even define wrecks by the type of engine that once powered the vessels! Needless to say, there are wrecks for all tastes.

Of particular interest to those divers who are lucky enough to live close to charter operations on either side of the Atlantic — but also in various other “hot-spots” around the globe — are WWI and WWII casualties. These include all shapes and sizes of freighters, ore-carriers, oil tankers and the various escort vessels that accompanied them during the years that raw materials, gasoline, food, and other wartime supplies were being shipping between North America and Europe in order to keep the allied war-effort on track. As well, the list of sinking’s includes a great number of Nazi U-Boats that preyed on those convoys.

The wrecks of Truk Lagoon in the Pacific nation of Micronesia, are famous as perhaps the pinnacle of war casualty shipwrecks. A great part of their appeal is that many still have in their holds and on their decks an assortment of the materials they carried including aircraft, tanks, trucks, and of course, bombs, torpedoes, guns and ammunition. What makes them especially attractive visually is the marine life, both invertebrate and vertebrate, that has colonized them, and it is not unusual to see more than a hundred different species of fish, coral and sponges on one dive.

Another destination for those who appreciate this type of historic wreck is Scapa Flow off the coast of Scotland. It is home to the scuttled WWI fleet of the German Imperial Navy and it’s a must see for those who appreciate diving on full-sized fully-armed warships.

Those divers fortunate enough to live within striking distance of North America’s Great Lakes have the largest collection of accidental wrecks to visit. These range from the remains of old barges and working boats sunk in a few metres/feet of fresh water, to gloriously intact schooners and steam yachts well below the thermocline at depths that can only be explored by technical divers. The scope is vast and as Cris Khol — a well-known author of diving books once commented — the history of the brave souls who built Canada and the United States is written large on the bottom of the Great Lakes.

I like diving all wrecks, but a special favorite of mine is artificial reefs, or intentional wrecks. These are often working boats and sometimes decommissioned fighting ships that have been cleaned and made ready for sinking as playgrounds for divers to visit and wildlife to use as a habitat. The West Coast of Canada and the Atlantic and Gulf coasts of Florida are home to some especially neat wrecks of this type and each year, more are being added to the inventory, thanks to various organizations that do the massive amounts of leg-work needed to get the permission to put a huge “diver attraction” on the ocean floor.

What appeals to me is that these wrecks are made much safer for divers to explore. Wires, bulkheads and other potential entanglements have been removed, along with contaminants such as bunker oil. However, much of their original equipment has been left intact, making them safer to dive than the average war casualty, but nevertheless interesting to explore.

One of the best treats I can imagine for a new diver is to discover just how much there is to learn about making wreck diving fun. If you’re new to diving — or even if you have a bunch of logged dives under your belt, but have not discovered the pleasure of wreck diving — sign-up for an SDI Wreck Specialty Course and a whole new and exciting world of opportunity opens up!

SDI Wreck Diver Course –

SDI Wreck Diver eLearning Course –

TDI Advanced Wreck Diver Course –

Basic Wreck Diving vs. Advanced Wreck Diving


Photo Provided by Bill Downey

Divers are often confused between basic and advanced wreck diving certifications and why there is a need for two courses. This is a good question considering a wreck is a wreck and diving is diving. All wrecks present the same risks. The single biggest difference is the diver and what they want to do during their dive on the wreck.

Basic Wreck Diving
Basic wreck dives would consist of swimming around the outside of the wreck, with the occasional peek in the wheelhouse or cargo hold. That does not mean there is not a lot to learn, even though the plan is to stay on the outside, or that there is not a lot to see. For divers wishing to survey the wreck or watch the marine life it attracts, this is the perfect spot. The outside of a wreck is also where we get those dramatic photographs of the bow stabbing towards the surface, hoping to sail again. For the diver wishing to view a piece of history, diving on the wreck can show you what some will only read about or see in pictures. This type of wreck diving has been enjoyed by many and for some divers this is as close as they want to get to a wreck.

The equipment needed for a basic wreck dive is pretty much the same equipment used for any dive. There are some pieces of additional equipment that may come in handy: a large slate for drawing the wreck and noting depths and features, a small reel, and a lift bag or surface marker buoy (SMB) just in case you lose track of the anchor line or get blown off the wreck.

Advanced Wreck Diving
Advanced wreck diving is really an extension of basic wreck diving. Advanced wreck diving starts on the exterior with a survey that familiarizes the diver with how the wreck is oriented: on its keel, on its side, separated into halves or with a twist. No two wrecks are the same and all suffer different damages due to how they sunk, how long their journey was to the bottom or the severity of the storms that have battered them over the years. There are even vertical wrecks and wrecks clinging to the side of walls. Learning how to effectively survey the wreck is an extremely important part of any wreck course. This visual image, is the only thing the diver will have to rely on, since his compass will not work. Even wooden wrecks tend to have massive hunks of metal or boilers, which send the compass into a spin. But here is the point where advanced wreck diving waves goodbye to basic wreck diving; it is where we go beyond “the light zone.”

The light zone is where ambient light enters an overhead area and artificial light is required in order to see. Once a diver enters an area in a wreck where a light is required, the rules of wreck diving change. A diver in this area must have the knowledge and skills they need to go into and come out of a wreck should the worse possible scenario, a complete silt out, occur. In order to do this, divers must know how to use a reel for navigation and how to properly tie off lines so they will not get cut during the dive. But this is also where the fun starts for wreck divers craving to study the more intimate details of the wreck or seeking that hidden artifact that no one else has seen.

Many wreck divers don’t feel they know all there is to know about a wreck until they have explored every room, seen the engines that pushed this once mighty vessel through thousands of nautical miles. There are also those who want to see the artifacts, some still lying in place as if the ship had never sunk. To some, the best part of the wreck dive started before they even entered the water, it was the hours of researching and planning that lead up to the dive. But before a wreck diver can see these sights they need to undergo serious dive training and have an experienced TDI Wreck Instructor explain the safety protocols. Remember that worst case scenario of silting out? For divers who spend their time on the outside of a wreck, this silt would only come from the fin thrust as it hits the bottom or deck of the boat. For divers entering the wreck, this silt comes from above and is called percolation silt, cased by the exhaled bubbles as they dislodge rust, insulation or other debris trapped on the ceiling.

Another big area of difference between basic and advanced wreck diving is the equipment needed. Advanced wreck divers should carry at a minimum two lights a primary and a back-up, two cutting devices, two reels, two lift bags and a redundant air supply. While this may sound like a lot of equipment, a TDI Advanced Wreck Instructor can teach divers where to stow this equipment and still keep very streamlined in the water.

Wrecks have a mysterious calling to many people. Wrecks that occurred due to war or sank because of a violent storm draw divers in, some say this is because it closes that chapter in our lives. Others would go there because they read about it in history books and they wanted to see it firsthand. Whatever the reason, or if you are going to view the wreck from the outside or inside, it is always best to take the course from an instructor who has been there and done it. Sometimes the best lesson learned from a course is not what is in the book or the skills you had to perform, it is merely what you learned by diving with and watching how an experienced instructor handled himself underwater.

Every wreck has a story, even the ones that were sunk intentionally. So do yourself a favor…find out what that story is! Safe diving!

SDI Wreck Diver Course –

SDI Wreck Diver eLearning Course –

TDI Advanced Wreck Diver Course –