SDI’s Solo Diver Course – How to Market It

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Solo-DiverAt one point or another, a diver has found himself alone during a dive, whether it was intentional or not. Solo diving is the practice of scuba diving alone, without a “dive buddy.”

Solo diving, once considered technical diving and discouraged by most certification agencies, is now seen by many experienced divers and some certification agencies as an acceptable practice for those divers suitably trained and experienced. Rather than relying on the traditional buddy diving safety system, solo divers should be skilled in self-sufficiency and willing to take responsibility for their own safety while diving. The first training agency to offer a Solo Diving certification was Scuba Diving International (SDI) in 1999.

Marketing the SDI Solo Diver Course is not as difficult as one may think. Divers who travel alone, divers highly involved in with photo or video as a hobby, divers who dive with their younger children or with a dive buddy who has considerably less experience than they do, underwater hunters, dive professionals with students, divers who dive in low visibility or are in areas with high currents that may cause the group to separate from their DM or dive buddy…these are all divers who would benefit tremendously from this course. Divers may not always plan to dive alone, but they may find themselves in circumstances where it happens and the added training and additional equipment can be the only elements that get them through a potentially sticky situation.

It is also not unusual for a diver to want to reach the highest levels of training possible, without leaving his or her comfort zone. This means they do not want to invest time and money in tech diving and are not interested in become a dive professional. The Solo Diver program is the one in which they are interested.. As an SDI Dive Center, you can now offer this demographic the ultimate goal in self reliance and confidence as a Solo Diver.

Some divers, such as instructors, are effectively acting as self-sufficient solo divers because they dive with students who may not yet be capable of rescuing them. Others, such as underwater photographers and videographers, dive alone as this allows them a greater opportunity to focus on capturing selected images and not having to rely on buddies to remain close at hand. Even those photographers or videographers who do dive with buddies are often effectively “same ocean” buddies, implying they may be far enough apart physically, or sufficiently focused on their camera-related tasks, to be ineffective as a designated dive buddy—just as if they were diving in the same ocean, but not together. This practice has led to many highly-experienced underwater photographers diving solo, since they don’t commit to providing timely support to a buddy nor do they expect such support from a buddy. Underwater hunters also often elect to dive solo in order to focus on their prey. Many solo divers will happily dive in a buddy pair if diving with a known and trusted buddy, but otherwise dive solo in preference to being paired up with a potentially unreliable or incompetent partner.

Solo diving is not only a great way to add a value to an exercise through training; it is also great for gear sales. They should have a completely redundant set of all life support equipment (e.g. a complete, self-contained backup breathing gas supply). This redundant air supply typically takes the form of a pony bottle for most recreational solo divers, or the use of a twin tank set equipped with the capability of independent operation of each tank, for more demanding or technical diving. Additional pieces of redundant equipment carried include a second dive computer, a dive light and backup dive mask. As with all scuba equipment, the diver must be intimately familiar with this configuration and have the ability to access any of the equipment easily if it should be needed.

Qualifications for formal solo dive training as provided by SDI emphasize the need for experience and maturity in diving. In particular, the student pre-requisites for the solo diving certification course are:

  • A minimum age of 21 years
  • A minimum certification of SDI Advanced Diver (or equivalent)
  • Proof of a minimum of 100 logged open water dives
  • Depending on the country – a certificate of medical fitness

If you do not have your Solo Diving Instructor rating yet…what are you waiting for? Find a local Instructor Trainer in your region and get certified at the professional level. Target your customers who are the travelers, the photographers, the thrill seekers, the hunters, or simply, the customers who wish to increase their own training and confidence levels and offer them the SDI Solo Diver course out of your dive center.

Contact TDI SDI and ERDI

If you would like more information, please contact:

International Training
Tel: 888.778.9073 | 207.729.4201
Email: Worldhq@tdisdi.com
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Night Diving with Surface-Supplied Diving Systems

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by Steven M. Barsky

Night Diving with Surface SuppliedSurface-supplied diving gear is one of the safest types of diving systems available to the properly trained public safety diver. The benefits of a hard-wired communication system with an unlimited air supply cannot be denied. It’s simply hard to beat the proven reliability of this type of dive equipment, especially when you are diving deep, in contaminated water, or diving at night

The very first commercial diving job I went on I was assigned to the night shift, diving from a 250-foot long supply ship in the North Sea in 8-foot seas. It did not matter to the diving crew whether it was day or night; the diving went on around the clock. As the first diver climbed the ladder and kicked off his expensive Jet Fins, abandoning them to the sea so he could get out of the water, I realized just how serious professional diving is, and how danger is always present. Public safety diving is no less risky, but every opportunity must be taken to minimize risk. Admittedly, commercial divers sometimes accept risks that no right thinking public safety diver would take.

Probably the most difficult part of learning to dive with a surface-supplied diving system is coming to grips with the management of the diving hose, or “umbilical.” Whether you are diving in black water or night diving, knowing where your hose is at all times is fundamental to safe diving with an umbilical system. The corollary to this is that your umbilical must never go under any obstruction that would prevent a direct ascent to the surface; since as a surface-supplied diver, you are obligated to follow your hose back to its origin.

If you manage to take a turn around your descent line (down line) or go under an obstruction, like a wreck or a pipeline, in the event of an emergency, you will be prevented from making an unimpeded ascent. In these circumstances, especially in black water, it’s unlikely you will be able to sort out this situation if you are panicked. This is part of the reason it is so vital to always know where your umbilical is located. Prevention is key; always go over any obstruction you may encounter, and when ascending, always come up on the same side of the down line you made your descent on.

Most umbilicals used by public safety divers today are made with a thermoplastic hose that not only is highly chemical resistant but also floats readily. This combination of characteristics makes them ideal for surface-supplied diving and will help to prevent entanglement. While some people think the risk of entanglement might be higher with surface-supplied gear, this is simply not the case.

Of course, it’s always essential to wear a bailout bottle whenever you use a surface-supplied diving system and using one while diving at night or black water is vital to your safety. Use the largest bailout bottle you can comfortably carry. For dives deeper than 60 feet of seawater, the cylinder should be an 80 cubic foot bottle.

Surface-supplied night diving need not be more hazardous than diving during daylight hours. Like any working dive, the job must be approached with the right training, the right equipment, and sufficient practice to help ensure the diver’s safety. Trying to make a rescue or recovery without adequate training and practice is always a recipe for disaster.

About the author:
Steven M. Barsky is a TDI/SDI instructor and has authored diving textbooks for SDI and other training agencies. He is the author of Diving in High-Risk Environments and Investigating Recreational and Commercial Diving Accidents. He also produced the DVD video, Choosing and Using Full-Face Masks. You can reach Steve through his web site at www.marinemkt.com.

Contact SDI TDI and ERDI

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Knowledge Does Not Have To Be Lost

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KnowledgeI used to be a flooring contractor. As a firefighter, I had to have a part time job to make ends meet. We did custom work for around 17 years. Now it physically hurts me too much to do the work, and I have to contract out work at my own home. Not only does this just irritate me, it has taught me a valuable lesson – one that my friend Buck has been hammering me about for years.

Because of a water leak, we were forced to do some remodeling in our home. I wanted to salvage some of the wood floor in the front of the house and use it in what used to be our kids’ rooms. That way the back of the house would all have the same flooring and the main room would be changed out. In essence, I would salvage and save about $2,000 worth of existing flooring.

While not a simple proposition, I know how to do it and, back in the day, would have easily managed such a project. Since I cannot do it now I had to find someone who could. We managed to find a contractor who said he could do the job. He has been in the business for 30 years, he says. We talk and he understands what I want to do and seems like he knows how to do it. The next day he gives me an outrageous bid and tells me he is unsure he can do the job but will try… “Forget it,” I say; we will just spend the extra money and put down new flooring. That’s two grand wasted because of his lack of knowledge and confidence.

Later that night I start thinking about how I would have done that job if I had been asked to do it. It would have been pretty simple. All you have to do is X, Y, Z. I know how to do it. It is not something most installers would normally run across. My experiences over the years with the various products we installed gave me the knowledge and ability to do it and do it right.

I have been teaching the same team for over 30 years. I get new members every year and have to start over each time. Those team members who have been around for a while know the basics well enough. But back in the day, we were a lot more active. We made numerous dives and had three active training days a month. Back in the day, those divers were extraordinary. Back in the day, because of the time we were afforded, I was able to teach more.

In the realities of today’s economy, we are no longer afforded the same amount of time for training. We are still tasked with the missions and expected to perform.

Our teaching dynamic has changed. We now find ourselves doing on-the-job training, and I find myself teaching more on mission scenes than ever before. It is not what we would like but it is what we have to do.

Our current team is good. Not great, but good. They are able to do the job they are called on to do and we augment their lack of training time with extra supervision on mission calls. Sometimes it is not pretty, but they get the job done and they do it safely. On those dive calls, I find myself sharing tips and tricks more than teaching. They know the basics and what I am able to offer are techniques or tricks learned over the years that were never taught in a class. More importantly, some of the older divers on the team are doing it as well.

We found a way to continue to build our team’s awareness, experience and education despite the lack of formal training hours. It is not perfect, but we are finding that even though the new divers are gaining experience slowly, they are learning. The team is good and on a path to be great.

Buck keeps hammering me about getting out and around more and sharing knowledge about Public Safety Diving. He says it is our responsibility to share our knowledge with others so it will not be lost. He does not mean just me, he means ALL of us who have been doing the job for more years than we want to remember. If those tricks and tips we learned by our own trial and error die with us, we leave nothing for those who come after us.

What have you shared lately and how did you do it?

Tell your story and send us an email to: PSDiverMonthly@aol.com

Mark Phillips ERDI 12472
Editor / Publisher
PSDiver Monthly
www.PSDiver.com

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A Brief History of Underwater Lighting Equipment

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In a perfect world, all underwater operations for public safety dive teams would take place in crystal-clear water with perfectly brilliant ambient light. Perhaps in that perfect world, many of the tasks carried out by PSD teams would also be unnecessary. But in the meanwhile, down here in the real world, we are called on to work in conditions to which we must bring our own lights if we want to have any illumination at all.

There is no generally used everyday technology that has undergone as many radical, fundamental changes as portable lighting; nowhere is this more apparent than with underwater lighting. Moreover, the changes have been complete, affecting both the power source delivering the energy and the lighting mechanism that converts that energy into light. We have, in effect, witnessed a revolution which has changed the way we approach limited visibility diving.

On first glance, the most obvious and most dramatic change has been to the device that converts chemical energy directly to electrical energy: the battery. As consumers, we are familiar with two types of battery: disposable and rechargeable, and both have changed dramatically in the past 10 or 15 years, which in turn has allowed the folks who design and manufacture dive lights to get pretty creative with their products.

The oldest form of rechargeable battery is the lead-acid wet-cell battery. What seems like a lifetime ago, if we wanted to take a “really powerful” light with us into the water to illuminate some particularly tricky and delicate operation, we took a light powered by a lead-acid battery. The first generally available semi-commercial lights made for cave diving — and used by PSD teams for low-light operations — were very heavy, very bulky incandescent lights using this type of power source; for all intents and purposes, a 12-volt motorcycle battery.

At some point the big improvement to the liquid electrolyte battery was the sealed valve regulated lead–acid battery (VRLA battery): popular in the automotive world, and cribbed by makers of underwater lights. These were still heavy (lead, right) and bulky but were somewhat easy to handle and less volatile during recharging.

Other portable rechargeable batteries that have made a showing over the years as the power source behind underwater lights include several “dry cell” sealed units. These were increasingly more powerful (power density) and developed for appliances such as mobile phones and laptop computers. Nickel–cadmium (NiCd), nickel–zinc (NiZn), nickel metal hydride (NiMH), and lithium-ion (Li-ion) cells.

In the underwater lighting market today, lithium batteries, and particularly Li-ion, seem the dry cell rechargeable that is most used. Lithium-ion batteries are common in most consumer electronics because of their energy densities, no memory effect, and only a slow loss of charge when not in use. They work very well in underwater lighting systems.

More on lithium cells in a moment, but now is a good time to sort out a couple of terms commonly used when we talk about lighting for divers.

In the days of incandescent lighting, we referred to a light as so-many watts and we accepted that as a way to grade how bright a light was. A 25-watt light was dim and a 150-watt light was much brighter, almost a spotlight. One of the early underwater lights this author had was 50-watts and, compared to the lighting used by the rest of the dive team, seemed bright enough to illuminate the wreck of the Titanic.

In fact, a watt has nothing at all to do with measuring how much light a light bulb or light source produces. A watt is the amount of power needed to move a one kilogram (2.2 pound) object at a speed of one meter per second against a force of one Newton. If that sounds a bit too close to the Physics 101 class you dropped out of your first year of college, let’s use terms we can all understand. Watts are a measure of the amount of energy something either uses or produces, and for the record, 746 watts is equal to one horsepower (nothing at all to do with light… well, not directly).

Lumens are a better unit to use. They are a measure of the perceived power of light that we can actually see. The nuts and bolts of what a lumen is and how it was derived is a little more complicated than that, but essentially, when it comes to comparing how bright a light is, specifically an underwater light, we are better off using lumens. In fact, in many jurisdictions it is required by law that lamps used for lighting are labeled with their light output in lumens and not watts. For example, an energy-efficient bulb that claims to be the equivalent of the “old-school” 60-watt tungsten bulb that most of us grew up with must have, by law in the EU, a minimum light output of 700-750 lumens. Clear as mud?

Having arrived at a relatively easy and standard unit of measurement to gauge the effectiveness of lights, let’s look at the apparatus producing the light itself.

Many of the truly tough and dependable lights being used by technical divers, military divers and PS divers these days, use light-emitting diode (LED) light sources, either an array of them or a single LED. This technology has revolutionized light design, function, and dependability. A quick glance at the product catalogs of the major underwater lighting companies shows that LED lights are the current wunderkind of the consumer lighting world. More specifically, LED lights are being used more and more by PSD teams because of their robustness, efficiency and relatively high output to dollar cost.

And the market has several options available.

Among the many US-based companies, Light Monkey out of North Florida produce what they term LED Primary Lights in three different power levels. These lights are the traditional canister lights and the battery canisters are machined from solid Delrin plastic with the light head for their “top-of-the-line” model machined from aluminum. These lights are warranted to a depth of 500′ (150m).

The company’s brightest offering is powered by a 20aH Li-ion rechargeable battery providing 480 minutes of burn time and producing 1100 lumens @ 5600 kelvin.

Hollis, another US-based company that markets a range of dive gear that runs from rebreathers to mask-straps, sells a similar LED canister light system they call the LED25. It is powered by a lithium-ion Polymer rechargeable battery, and it burns at 1250 lumens for five hours.

However, canister LED lights are becoming old technology and as more advances are made with the power packs driving the LED “bulbs,” completely hand-held systems are becoming more popular. This option – either hand-held or attached to a helmet for more efficiency – is more compact and therefore preferred by many PSD teams.

The smaller hand-held LED lights (often referred to as back-up or secondary lights) produce as much or more light than the old generation canister lights with far less clutter.

Typical is the Light Monkey backup LED powered by a 2.6aH Li-ion rechargeable battery and producing 600 lumens at 5600 kelvin. This very small, very tough light provides 210 minutes of burn time on a single charge and weighs 400 grams, less than a pound.

But perhaps the most impressive “new generation” underwater lights are from Cathx Ocean. This European company develops advanced lighting systems for divers, ocean vehicles and fixed subsea and surface installations. The company uses proprietary and patented technology and really advanced microprocessor control and monitoring in all its lighting systems, including its PSD lights and video systems. In other words, they produce lights that are made for commercial environments and extraordinary service conditions, and their engineering philosophy is that NO failures are acceptable. Unlike their competition in the dive light market, Cathx are primarily a lighting technology company and the PSD and technical dive community have not been their primary focus, although this is changing. Their hand-held Ethos lights are currently under testing with the police divers in a large US city and, to date (12 months in), there have been zero light failures and a lot of positive feedback.

For the record, its Euphos hand-held light has user-controlled variable power output with 75 minute burn time at full power (1250 lumens) and three hours burn time at medium power in a tough anodized or Teflon finish on marine grade alloy.

Whichever way we look at it, underwater lighting across the board, hand-held, canister, LED and so on, is remarkable compared to that old lead-acid monster I started out with. The profiles now are tiny and compact, the light output remarkable, and – perhaps the most important improvement – their reliability is as close to perfect as we can hope for. Cost, too, is dropping relative to performance. Good lighting is not cheap but lumen for lumen, the price of underwater lights has dropped consistently. And in any event, when conditions call for light and plenty of it, cost is a distant second to value.

Contact SDI TDI and ERDI

If you would like more information, please contact:

Tel: 888.778.9073 | 207.729.4201
Email: Worldhq@tdisdi.com
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Lights for Public Safety Diving

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Dive-LightsWhen we think back over the years about dive equipment technology regarding some of the innovations and changes, the advances made with lighting technology are remarkable. From “housing” some lights decades ago to the current technology of LED and extremely small, powerful batteries, underwater lights are so improved.

So when we consider what kinds of lights are appropriate for PSD – especially given that the vast majority of dives are in conditions where no light could improve visibility – let’s put aside wide beam vs. narrow beam, rechargeable vs. standard battery, HID vs. LED, candlepower vs. lumens and consider a few factors that may not have been previously addressed.

One consideration is the decision to have hands-free operation or the traditional hand-held light. While some of the decision making process will depend on available budget, there are a number of options available from several manufacturers. In addition to the hand bracket, popularized by the cave diving community which allows a light head to be mounted on the back of the hand allowing use of the hand, there are also mounting options utilizing rail systems or mounting brackets that can be installed on full face masks or fully enclosed dive helmets. These light heads may be powered by separate battery containers connected by cord or may be a completely contained light including battery power. This option is available for hand brackets as well.

Another over-looked feature to consider is, “do we need a light that is safety rated or explosion proof?” While at first glance this may seem unimportant or irrelevant, consider this: often smaller hand-held lights that are used underwater are also used topside by tenders and other team personnel. Given that any call can potentially result in a scene with flammable material present, perhaps it should be a consideration to have smaller handheld underwater lights that are at a minimum Class 1 rated. For law enforcement PSD’s, Class 1 safety rating essentially means the light can be safely used in environments where flammable gases, vapors or liquids are present. Often these lights provide a narrow beam that is useful for not only cutting through smoke but also turbid water.

When purchasing underwater lights, it’s quite normal to be confused by some of the descriptions used as they relate to how powerful or bright the light is. Two terms used are “candlepower” and “lumens.” Both refer to candela which measures the power emitted by a light source in a given direction. Candlepower, once used extensively, is no longer used and is outdated and refers to the light emitted by a single candle of a specific size. Lumen is a more accurate method of light measurement that addresses exactly how much of the emitted light the eye can see. While it is easy to get caught up in the numbers, keep in mind the environment in which the light is used when considering brightness and bulb focus.

The options available to ERDI teams are many. However, after considering budgetary issues, selecting a light that fits the team’s needs, is durable and easy to maintain, provides needed brightness—and this is the most important part—doesn’t have bubbles coming out of it at depth, is really the criteria that should be considered.

Contact SDI TDI and ERDI

If you would like more information, please contact:

Tel: 888.778.9073 | 207.729.4201
Email: Worldhq@tdisdi.com
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Underwater Lights for Tech Diving

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Hollis-LightTechnical diving has evolved rapidly in a relatively short period of time. In less than 20 years, roughly the period of time technical diving has been ‘main stream’, we have seen: the development of technical diving equipment rather than modified sport equipment, computer generated multi gas dive planning software as opposed to manual planning using dive tables and formulas, and finally closed circuit rebreathers readily available. But few of these advancements have made as much progress as dive lights used for technical diving.

The early technical dive lights were modified from sport lights or very bulky, very heavy halogen lights with batteries that felt like they came from a Mack Truck and light heads that would give your arm fatigue – and all this for a little extra burn time and a brighter light. A lot of technical diving takes place in limited visibility, which is not always a factor of the clarity of the water. Many times limited visibility is caused by other aspects of the dive, such as overhead environments blocking the light (caves & wrecks) or the depth of the dive (too deep for sufficient light penetration). For technical dives conducted on wrecks, your buddy’s light can be used for underwater navigation, keeping track of the buddy team and still allowing a little distance between divers. This advantage has become better and better through the years, first with the new HID lights: lights were brighter, light heads got even smaller and burn times longer. Now with LED, lights are even brighter than HID, their heads even smaller, burn times twice as long and battery canisters the size of soda cans.

Along with the advancement of primary light has come the advancement of back-up lights; they too got smaller, brighter and longer lasting. These small back-up lights can be critical pieces of equipment when diving. If a diver finds himself deep inside a wreck or way back in a cave, and his primary light has failed, odds are good that he will never get lost if he has a back-up light ready to go. Some divers carry two back-up lights. These small backup lights can also be strapped to a marker buoy if the diver notices surface conditions have deteriorated or the dive went a little longer and became a night dive. This was not an option with the earlier, larger dive lights; cyalume sticks were commonly used instead.

For the longtime tech divers or the newly certified, take a close look at all your options for primary and back-up lights and choose carefully. With the size of the new lights, they make it very easy to stow away, without causing an imbalance in your trim and allowing a streamlined position in the water. Also with the new battery technology, divers can charge up their lights once and get four to five dives out of them. Pretty impressive!

For new or longtime tech divers wanting to know more about lighting options for technical diving check out TDI’s Intro To Tech Course or search for a TDI instructor in your area to discuss some options.

Contact SDI TDI and ERDI

If you would like more information, please contact:
Tel: 888.778.9073 | 207.729.4201
Email: Worldhq@tdisdi.com
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A Night Dive Turned Inside Out

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National-GeographicWant to try something really cool? If you like night dives, this may be something for you. As Buddy Dive’s March Storm from Bonaire likes to call this, “A Night Dive Turned Inside Out”. The general idea behind a “normal” night dive is to go for a dive with a flashlight to witness the amazing activity that can only be seen once the sun has set… the creatures of the night. You can take this one step further with what is known as a fluorescent night diving experience, or glow dive.

During a glow dive, divers use a special UV Light and a Special Contrast Lens that goes over their masks for a combined effect that produces a very different sort of underwater glow. People who have experienced this type of night dive have called it “a psychedelic effect.”

When looked upon under a ultra-violet light, much marine life, especially invertebrates and corals, emit a different wavelength of light, displaying distinctive colors than those a night diver may witness with a standard underwater flashlight. The phenomenon, known as fluorescence, happens when the coral itself appears to glow in shades of green, red or blue.

Inside-OutThough there is no real scientific explanation for this just yet, a common theory is that it acts as a kind of “sun block” for the coral, protecting the zooxanthallae inside from the harmful rays of the sun. This is particularly true to those coral reefs closer to the surface.

The dives start at around 6:30 in the afternoon right off the dock at Buddy Dive Resort. Enjoy the show while your guide leads you into the other-worldly night dive.

One participant of the excursion explained: “This unique Night Dive experience is quite like Alice falling down the rabbit-hole. You will see corals like you have never imagined, in colors you have never seen underwater. Creatures that you were never aware of before will captivate, amaze and delight you.”

Some of the marine life that jumps at you right away include fire-worms, lizard fish, anemones, finger corals, star corals and the sharp tail eel.

TDI, Dive Rite and Buddy Dive are hosting the Tech Diving event from October 13th through October 27th at Buddy Dive Resort. With as many as 60 officially listed dive sites on Bonaire, most of them easily accessible from shore, Bonaire offers the perfect conditions for tech divers. Forget about the hassle of carrying your heavy tech diving gear onto boats, heading out for a long boat ride and hoping for good visibility. If you do decide to come and see us – be sure to ask about the night dive turned inside out.

Contact SDI TDI and ERDI

If you would like more information, please contact:
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Does It Have to be Night for Low Visibility Dives

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Low-VisibilityWhenever we talk or think about low visibility, we almost always think in terms of a night dive. This makes perfect sense, but not when we are planning a technical dive. Technical dives have many aspects to consider; first and foremost being the appropriate gas to breathe if we are going to deeper depths or the right amount of gas if we are planning a longer dive. Whatever the technical dive is, preparing as if it were going to be a limited visibility dive should always be part of the planning phase.

Limited visibility comes in all shapes and sizes: reduced light due to depth, limited light due to overhead (wrecks) and no light due to overhead (caves). Each of these factors requires slightly different considerations and all should be considered limited visibility diving. There are some other factors that can turn what should be a good visibility dive into a limited visibility dive. When diving in wrecks exhaled bubbles can dislodge silt, rust or fragile building materials from the ceiling of the wreck. There are also the times when divers in front of you kick up silt in both wrecks and caves which can sometimes bring a dive to no-visibility.

One of the key objectives is that you never get lost, and the same goes for your buddy or team. There are many ways to maintain contact with others underwater and to perform underwater navigation so you don’t get lost. Dive lights allow you to stay in contact and communicate with others on the dive team, reels allow you to run a line leading back to the exit point and, when not around ferrous metals, a compass will do the trick. If the dive is or becomes a limited visibility dive, your options are reduced. Any time a diver is in an overhead environment, wreck or cave, they should also have a line that leads them to the exit point and contact with the line should always be maintained.

With minimal additional equipment and very little additional dive planning, limited visibility diving can be accomplished. Some of the best dives can be performed in limited visibility and for some sites, limited visibility is the best it will ever get.

For more information on limited visibility diving or to locate an dive center in your area please visit us at /sdi/get-certified/Night-Limited-Visibility-Diver/

Contact SDI TDI and ERDI

If you would like more information, please contact:

Tel: 888.778.9073 | 207.729.4201
Email: Worldhq@tdisdi.com
Web: https://www.tdisdi.com
Facebook: www.facebook.com/TechnicalDivingInt

Never Get Lost on a Night Dive or “I’m Pretty Sure I Know Where I Am….”

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You know some of my best dives over the years have been night diving and while some of the coolest critters are out at night or readily seen “napping,” one of the more enjoyable aspects for me was the darkness. It just seemed to be quieter and more peaceful, although in reality, everything that was happening during daylight was still going on at night –  plus a whole lot more!

On the other hand, it is quite normal not to have those comfortable feelings when entering the water at night, and to approach a night dive with a little well-placed apprehension and caution. That’s perfectly normal. When the ambient light is gone, certainly one may have thoughts of losing situational awareness – how will I navigate underwater or return to my starting point? After all, we don’t want to get lost.

There are a number of precautions and actions that we can take to prevent getting lost and to minimize or eliminate any dangers of a night dive. Let’s look at some of these:

  • Planning a night dive. Planning should occur for every dive we make and it becomes even more important for a night dive. With your dive buddy, decide on the location, consider environmental, such as tides, currents and entry point, and also ask yourselves “Is the dive site appropriate for a night dive?” In addition, review any light signals that you are likely to use to avoid any confusion about the signals. Decide on what your activities will be and finally ask “Am I ready for a night dive?”
  • Once planned, give this dive plan to somebody staying who is onshore or on the boat, just in case things do not go according to plan.
  • • How are your underwater navigation skills? Make certain your compass is positioned correctly for use, whether analog or electronic, and that you are familiar with it. If starting from shore, make note of the direction that the shore runs…say southeast to northwest for example…and also which point on the compass is the water. If you’re standing on the beach with the water in front of you and the compass is showing a heading of 100°, then returning to shore will be 280°. One of the best methods of becoming comfortable with compass use is to enroll in an Underwater Navigation course. Along with increased skill levels, you’ll also learn to trust your navigation instruments. We should also make note of the natural surroundings that often reveal direction.
  • Do you have night diving equipment? Besides the standard open water equipment in your kit, a good primary underwater light will be necessary. If the light includes a rechargeable battery, make sure it is charged. If you’re using replaceable batteries, have fresh ones installed. In addition, having a smaller backup is an excellent idea to ensure that in the event your primary fails, you’ll have a light to monitor your instruments in order to end the dive. In addition, consider having a small battery operated strobe light attached somewhere on you or your equipment. This will assist your dive buddy in knowing exactly where each of you is at any time. Also consider placing a strobe on the anchor line or float line to assist in identifying where your exit is. If not a small strobe, consider one of the battery operated LED Glow Sticks.
  • As we mentioned lights, if you are conducting a shore dive at night, placing two lights in alignment onshore will assist you in determining the exit point when you surface. One light, in the back, should be slightly higher than the front light. Observing that the front light is left or right of the rear light will indicate which direction to proceed to exit.
  • If you are night diving from a boat, check with the boat crew to determine any special rules the boat may have for night diving. Make note of any lighting system the boat has to assist you in identifying the right boat.

Using common sense and diving within your training and abilities will go a long way to keep you from getting lost while night diving. To have an even more enjoyable experience, consider visiting your local SDI dive center and enrolling in an SDI Night Diver course. It’s a lot of fun, it will provide for new experiences and it will teach you valuable night diving skills.

For more information about night diving or to locate an SDI dive center in your region, call 888.778.9073.

Contact SDI TDI and ERDI
If you would like more information, please contact:
Tel: 888.778.9073  |  207.729.4201
Email: Worldhq@tdisdi.com
Web: https://www.tdisdi.com
Facebook: www.facebook.com/SDITDI

 

The Attraction of Night Diving… Not Everyone’s Cup of Tea, but Strangely Addictive for Most

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Diving at night is one activity that puzzles many new divers, and certainly baffles those who are just thinking about becoming divers. “Can you do that?” “Is it safe?” “Is there anything to see?”

All good questions, and all have similar answers that boil down to “Yep!” And for many of us, the real question is not so much can you do that, is it safe and is there anything to see, but more likely when can we go again?

One of the lures of night diving is that many underwater animals are hidden during the day and only come out to feed and generally interact with their environment at night. Many true fish, invertebrates, crustaceans and mollusks are night-shift workers and, in some area, darkness brings out species that cannot be seen at any other time of day. Even those species that do show themselves in daylight have unique nighttime behavior.

Although visibility under the water is obviously restricted by darkness, night diving does not present the same challenges as diving in low-visibility situations where silt and other particles suspended in the water limit a diver’s visual field. Typically night diving locations – those spots famed for this type of diving – have very good water clarity, and this is heightened by the field of vision being concentrated into the cone of light from the diver’s light.  The dive light enables the diver to focus his attention on the objects that his dive light illuminates. Everything else tends to disappear. It’s a fascinating change of perspective that seasoned night divers find really appealing.

In short, night diving can provide a truly unique and extremely rewarding experience; however, to be done correctly, a night dive needs to be properly planned and organized.

As with other types of dive plans, all the normal guidelines should be followed.  In addition, there are a few other tips that will help to keep everyone safe and sound.

One of the major issues is that contact and communication between divers and their mates back on the surface, can be challenging. These issues demand special planning and equipment. A lost dive buddy is never fun but on a night dive this situation can be even more distressing. Potentially more challenging is buddy separation combined with disorientation and loosing track of the safe exit point location.

But before we touch on some of those issues, something worth considering is the timing of a night dive. Twilight is a favorite time to start a night dive. For one thing, ramping up for a dive when there is sufficient daylight to see clearly and not trip over gear and rocks and so on is a real bonus. And even though there may be sufficient light on the surface, the low-angle of a close to setting sun does not penetrate the water well and ambient light on the coral or seabed is much weaker than at mid-day or in the afternoon. The marine nightlife kicks into gear before it is fully dark on the surface. Bearing this in mind, some night diving starts and finishes while there is still enough light on the surface to gear up and to make post dive “recovery” simple.

For a really one-of-a-kind dive, plan a “dawn” dive. That’s to say, begin your dive 30 or 40 minutes BEFORE the sun comes up, and watch the change of shifts as the daylight creatures wake up and start their activities and the night owls turn in for the day.

Even if you have planned a “total” night dive, there is usually some ambient light. Jetties, quays, beachfront properties, street lights, even the lights on a dive boat can supply a surprising amount of light when shore or boat diving at night.Also, a full-moon can be a major illumination source. But perhaps the best and most fascinating light supplied by something other than underwater dive lights is bio-luminescence. This is the eerie and colorful light triggered when water filled with phosphorescent plankton is disturbed making these tiny creatures give off a remarkably strong and powerful glow.

Of course, a correctly equipped night diver takes his or her own light source. In fact, a primary light and at least one back-up light per diver. A proper dive light allows a diver to see clearly underwater. The scenery literally comes alive because animals and plants that look blue or black in ambient daylight show their real colors. Modern dive lights are powerful, produce a full-spectrum white light, and are becoming more and more compact every year. Many of the more expensive models have rechargeable batteries but there are really serviceable lights that produce several hundred lumens for several hours with user-replaceable AAA and AA batteries that can be purchased around the world.

Dive lights also serve as a primary tool for communications on a night dive. The glow from a buddy’s light helps divers to keep track of each other at depth. Communication between divers is easy when they shine their lights on their hands and use normal diving signals.

A light can also be used to get your buddy’s attention. While care should be taken not to shine your flashlight into your buddy’s eyes – since this will spoil their night vision for some time – moving a light from side-to-side or up and down, or covering and uncovering the light can all signal to a buddy to look your way.

Buddy lines can be used on night dives, but with decent visibility, buddy awareness and some simple ground rules learned in an Night Diving Program, they should not be required. With a little care and practice, buddies can keep tabs on each other by watching for their lights.

But what happens if a light fails during a dive? This is one reason night divers are advised to carry a backup dive light and at that point to signal their buddy and terminate the dive.

Flashlights are also useful when “communicating” with the surface. All night dives should be conducted with at least one person topside, whether diving from a boat or from shore. The simple reason for this is that they can help illuminate the exit, and can signal to divers if they surface well away from the designated surface point. The surface support is also where a dive plan is “filed” so that if something goes awry, they can immediately summon help.

When the wind is calm and the surface flat – the suggested conditions for night diving – voice communication on the surface is quite effective too.

When shore diving, it is best practice to arrange lights so that from the water, they indicate to divers exactly where to come ashore. This simple solution is the easiest way to make sure that divers do not get lost or disoriented when their dive is over.

The perfect site for a night dive is a sheltered bay or cove that provides easy navigation and facilitates entry and exit. The site should not be deep, and MUST be a site that divers have familiarized themselves with in daylight. One of the coolest things to do on a night dive is to compare what’s seen and what is going on with the same area during the day.

Try it… chances are you will love it!

REMEMBER THE BASICS:

  • Night diving offers divers a remarkable challenge and unbeatable fun as long as it is conducted within some common-sense rules.
  • Choose a familiar site that is sheltered and shallow.
  • Start at twilight. Gearing up is easier when there is daylight to work with. As the light drops when you are underwater, you’ll gradually become acclimated to the ambient light levels.
  • Plan short, shallow dives, and be conservative with gas needs. Night divers generally use more gas on night dives.
  • Carry at least two dive lights, a primary and a smaller backup.
  • See and be seen. Reflective tape on tanks will help your buddy pick you out if there are several divers in the water. Glo-sticks (chemical lights) have fallen out of favor because of environmental concerns, but there are several manufacturers who make a battery-run alternative. Small compact and low-lumen, these are a great aid to divers who are a little nervous about losing touch with the group or their buddy.
  • Use basic navigation aids… natural and man-made.
  • Have someone on the surface to help when the dive is over and file a dive plan with them so that they know when to expect you back.

Sign up for your SDI Night Dive Specialty by visiting your local SDI dive facility.

Contact SDI TDI and ERDI

If you would like more information, please contact:
Tel: 888.778.9073  |  207.729.4201
Email: Worldhq@tdisdi.com
Web: https://www.tdisdi.com
Facebook: www.facebook.com/SDITDI