Of all the Frequently Asked Questions in Scuba Diving, queries regarding the proper time to fly after diving is one of the most common asked. The dilemma usually crops up, cos as divers we are always keen to squeeze in those few extra dives just before we have to make the most of our diving trips, after-all you just heard the other divers spot a manta ray at a particular dive site, what if it’s still around this afternoon? or you really wanted to have one last look at the amazing Electric Flame Scallop you’ve never even heard of before…whatever the reasons you’re wondering whether it’s reasonable to dive on the day of departure or the evening/night before an early flight.

The U.S. Navy tables recommend that you wait at least two hours before you board a plane after scuba diving; the U.S. Air Force says you should wait 24 hours; DAN recommends a 12-hour minimum surface interval before flying; PADI Flying After Diving guidelines say that you should not go to an altitude (fly) within 12 hours of completing a single dive or 18 hours when doing multiple dives (where possible wait 24 hours)….So which guideline should you follow?

Truth of the matter is that ascending to an altitude immediately after diving causes a significant risk for decompression sickness. Flying after diving, increases this risk because of the decreasing atmospheric pressure as we ascend. You might have only a few tiny bubbles, causing no problems at all, in your body when you reach the surface after a dive. If, however, you go flying, the small bubbles can expand (due to the reduction in pressure with altitude) and could cause the onset of DCS symptoms.

So what’s the minimum time you should give before flying after diving?
Unfortunately, there’s no straightforward correct answer to the question. It all boils down to the risk you are willing to take.

The current winner of the debate is a DAN guideline which states:
a. A minimum surface interval of 12 hours is required before ascent in a commercial aircraft (8000 foot (2438 m.) cabin).
b. Wait an extended surface interval beyond twelve hours (18 hours or more is suggested) after daily, multiple dives for several days or dives that required decompression stops.
c. The greater the diving the longer the duration (some sources say 24-48 hrs) recommended before flying.

The above is for sports diving and should not apply to commercial diving or nitrox diving. Because of the complex nature of DCS and because decompression schedules are based on unverifiable assumptions, there can never be a fixed flying after diving rule that can guarantee prevention of bends completely.

Whether you wait 12 hours or 24 hrs there are no guarantees that you won’t get decompression sickness when you fly. However, the longer your pre-flight surface interval time, the more nitrogen you expel from your system which minimizes the risk of decompression sickness. We recommend you use your judgment and consider some factors before making your decision like- The number of previous dives you’ve made on this dive trip, type of dives (decompression, non-decompression, altitude dives, nitrox etc), your general health and your age. The estimated DCS probability for the 12-hour flying-after-diving surface interval is about 1 percent. Of the 300,000 to 400,000 people who fly home 12 to 24 hours after their last dive, the estimated incidence of decompression sickness among these divers is about 0.004 percent, making the 12-24 hour rule the most followed among divers across the world.

*Photo Credits: photos by caribb, ianmyles, rsgranne on flickr

References:
Divers Alert Network

Even if you consider yourself a fit person, almost  every Scuba Diver has experienced cramping of their hamstring, calf muscles, or quadriceps or in the arc of your foot  while Scuba diving at some point or the other. When a muscle cramp hits you underwater, it can often be an agonizing experience. These muscle cramps caused by exercise fatigue when muscle fibers interlink and is known as EAMC or Exercise Associated Muscle Cramping.

EAMC occurs more commonly with divers in the four muscle groups mentioned above namely the calves, hamstring, quadriceps or thighs, mainly due to the finning action causing muscle fatigue in the legs triggering the muscles to spasm.  Cramping does affect those who have taken a long break from regular Scuba Diving more than those who have been diving regularly and exercising the specific muscle groups that cramp.

Divers are often told to eat a banana and drink plenty of fluids before a dive to raise potassium and hydrate to prevent cramping. This however has been scientifically proven to be incorrect, and the interlinkage between dehydration and muscle cramping does not exist.

EAMC can be prevented by maintaining proper physical fitness, exercising regularly, especially the muscle groups involved in Scuba Diving. Getting some pool hours for practicing swimming with your fins for a couple of hours each day leading up to your diving trip can help get your muscles used to the finning action. Well-conditioned, flexible muscles are less likely to cramp during exercise than poorly-conditioned, inflexible ones. We often don’t realize it but when we dive we are using our leg muscles for an hour continuously in a manner our muscles are not accustomed to being used. Stretching before and after a dive is also a good way to prevent EAMC for Scuba Divers.  Also check your fins whether your toes are curling due to a lose pair, or if the blades are too stiff causing undue stress on your feet.

Despite all your precautions should you still get a muscle cramp underwater, you should immediately stretch the affected muscle, and not relax it despite the natural instinct to do so. You want to tense the muscle and reduce the twisting of muscle fibers by stretching the muscle and giving it less slack. Relaxing a cramping muscle will only increase the cramping and pain. If your calf muscle is cramping,  firstly signal your buddy letting him know that you’re not okay, then grab the front tip of your fin pulling towards you to tighten your calf.  You can gently massage the affected area which will only help with the pain, but not with the cramping. Make sure you continue stretching that muscle even after the cramping has subsided. If the EAMC re-occurs then you should take the sign that your muscles are over fatigued and end your dive. Ignoring cramps is simply an irresponsible thing to do while underwater, and can put you and your buddy at unnecessary risk.

Maintain a fit, active lifestyle ensuring you condition yourself in a swimming pool before diving, and perform the necessary stretching before diving, and you should have an EAMC free dive.

Photos from flickr by : jayhem

Air embolism is a medical condition characterized by an air/gas bubble or bubbles in the bloodstream, which cause a variety of problems ranging from blockage of blood supply to organs, stroke like symptoms, and possible cardiac arrest if it reaches the heart.

The primary causes for air embolism other than Scuba diving is through air entering the bloodstream during surgery, massive trauma, air bubbles in injections, and intravenous feeds.  The severity of air embolism depends upon on the size of the air bubbles in the bloodstream. Air bubbles in arteries obstruct the flow of blood through the body, and depending on its location, can cause severe complications. For example an air bubble near a artery supplying blood to a vital organ such as a kidney can cause kidney failure. Often the embolism blocks supply of blood to the brain causing stroke like symptoms where the person loses consciousness.

Air Embolism in Scuba Diving can be caused by two reasons:

Pulmonary Barotrauma
Pulmonary Baratrauma is caused when air bubbles enter the bloodstream as a result of severe trauma or injury to the lungs caused by rapid ascent while holding breath. During rapid ascent  the air in the lungs expand, causing lung over expansion and rupture releasing bubbles into the bloodstream. Divers probably won’t even realize their lungs have ruptured as lungs give little warning in the form of pain. Symptoms to spot Pulmonary Barotrauma are the diver surfacing in pain and discomfort, blood or frothy blood from the mouth. Divers showing symptoms of pulmonary barotraumas should immediately be treated for air embolism as well.

Decompression Sickness (DCS)
If the gas dissolved by the bloodstream isn’t given enough time to escape the body through decompression stops, then the trapped air is likely to form air embolism, which much less noticeable symptoms . Air embolism caused through DCS is often difficult to spot and are potentially more dangerous as they can form in the arterial system, the bubbles are smaller and they can travel to and lodge in the brain where they can cause stroke. (Read: Decompression Sickness: All About Scuba Diving & The Bends)

Treatment
First aid treatment for both forms of diving air embolism is to administer oxygen, place the diver in the Trendelenberg position, a slanted position with the head facing down. This is designed to trap the air bubble in the apex of the ventricle, if it has reached the heart, and also slows the rate of travel, making the embolism less likely to reach the brain or heart. The effected diver must be taken to a hospital for treatment which often involves administering of pure oxygen, and placing the patient in a hyperbaric chamber under high pressure which will force the gases in the embolism to dissolve into the blood, clearing the embolism.

Photos by: mooste, Saspotato

In our previous post we stressed on one of the biggest risks of Scuba diving- Decompression Sickness (DCS) and the importance of every diver knowing all there is to ‘the Bends’ as it is also known. We covered What is Decompression Sickness in detail and What are the causes of DCS when scuba diving.  If you missed it you can read it here- Decompression Sickness: All About Scuba Diving & The Bends (Part-1).

Signs and Symptoms of Decompression Sickness

The symptoms of DCS normally appear anywhere from 15 minutes to 12 hours after diving. The symptoms may differ depending on the severity and where the bubble start forming. Mostly DCS can be classified medically into 4 types -

The Bends: In this type of Decompression Sickness bubbles form within the joints. 70% of all cases of DCS are reported to be of this type called DCS I. Symptoms include-

• A localized “deep” pain, tingle  or dull ache within the limbs or joints of the body such as elbows, shoulders, hip, wrists, knees or ankles.
• Movement of the limb or joint can aggravate the pain
• The pain may be reduced by bending the limb to a specific position

Skin Bends: In 10-15% of DCS cases bubbles form within the body’s upper tissue. Symptoms may be-

• Itchiness around the ears, face, neck, arms or upper torso
• A tingling sensation that can be described as insects crawling on the skin
• Mottled or marbled skin around shoulders, upper chest, abdomen with itching
• Swelling of the skin, accompanied by tiny scar-like skin depressions.

Neurological DCS: When bubbles form within the brain, spinal cord or nervous system it’s classified as DCS II. It accounts for approximately 10-15% of all cases of DCS.

• Headache
• Visual disturbances, spots in field of vision, double vision tunnel vision or blurry vision
• Confusion
• Memory loss/Amnesia
• Unexplainable extreme fatigue or behaviour change
• Seizures, dizziness, vertigo or nausea
• Vomiting
• Unconsciousness
• Abnormal sensations such as burning, tingling, stinging around lower chest / back
• Symptoms may work from feet up, bringing weakness in limbs / fatigue
• Abdominal / Chest pain
• Urinary or fecal incontinence
• General muscle weakness and twitching

The Chokes: Less than 2% of DCS cases come under this category. It is when bubbles form within the lungs causing sudden low blood pressure, slowing down of breathing and possibly shock. The symptoms are-

• Burning deep chest pain under the sternum
• Pain is aggravated by breathing
• Shortness of breath
• Dry constant cough

First Aid and Treatment for Decompression Sickness

Treating decompression sickness  quickly is very important. Diver’s Alert Network’s recommended first aid for DCS is:

• Request emergency medical attention
• Administer 100% oxygen to a breathing patient
• A breathing patient should lie down on their left side, a non-breathing patient should be laid on their back for CPR
• Transfer the patient to a recompression facility for medical attention
• The patients airway and circulation should be monitored until EMS arrives

Prevention and Avoiding Decompression Sickness

There are no dive tables or dive computers that can guarantee 100% a diver will not get DCS. But if a diver learns how to calculate dive time properly, stays within safe depth limits and ascends slowly from every dive while taking recommended decompression stops, they can lessen their chance of getting bent.

When planning multiple dives in a day, do your deepest dives first and then shallower dives. Always carry out a 5 minute safety stop, even on a no decompression dives to be on the safer side. Avoid flying 24 hours before or after diving.

ALWAYS plan your dive and dive your plan! Dive safe!

*Photo Credits: photos by utnapistim, Anglesey Divers, Boogies with Fish on flickr

One of the biggest risks of Scuba diving is Decompression Sickness (DCS), sometimes called ‘the Bends’, ‘Divers Disease’ or ‘Caisson Disease’. Knowing the facts and understanding all there is about decompression sickness is important for any person interested in the sport. While the basic decompression theory is covered in what you learn in an Open Water Diver certification course, we’re going to cover decompression sickness and its relation to scuba diving in detail right here.

What is Decompression Sickness?

Decompression sickness or ‘the bends’ is directly related to the Scuba Gas Laws- Henry’s Law in particular, which states that under pressure, a greater quantity of gas can be absorbed by a liquid. In a Scuba diver’s case this gas is the nitrogen that a diver breathes from the air filled in a scuba tank and the liquid absorbing it is his/her blood and body tissue.

Usually, nitrogen is expelled from a persons body during an exhale and through their skin. When breathing compressed air while diving, because of the ambient water pressure, the nitrogen is absorbed remains in the body’s fatty tissues and blood. The longer and deeper the dive, the more nitrogen is absorbed into the tissues. As long as the diver remains at pressure, the gas presents no problem. However, when the pressure around the diver decreases the nitrogen starts coming out of the tissues back into the blood stream. This is known as off gassing. If the pressure is reduced too quickly, the nitrogen starts forming bubbles in the tissues and bloodstream rather than being exhaled just like when you open a bottle or can of soda it releases the pressure causing the carbon dioxide gas to lose its solubility and escape in the form of bubbles or fizz.

The nitrogen bubbles that form in a persons body tissue can collect under the skin or within solid tissues inside the body causing severe pain as they collect near the joints. Bubbles that congregate within the joints are very painful and usually cause the person to bend over in pain which is why it’s called ‘the bends’. Sometimes however, the nitrogen bubbles can form in the bloodstream which restricts the flow of blood flow to the lungs causing sudden low blood pressure, slowing down of breathing and possibly shock. In extreme cases, nitrogen bubbles can form within the brain, spinal cord or nervous system column. This can result in paralysis and can even be fatal.

What Causes Decompression Sickness?

As we saw above, nitrogen bubbles start forming the body if pressure is reduced too quickly. When diving water pressure is reduces if a diver ascends too quickly. So, getting this nitrogen out of the tissues at the correct rate is a challenge divers face. When a diver ascends at the right rate and by stopping part of the way up, the pressure is released slowly and the gas diffuses from the tissues through micro-bubbles that can be exhaled safely. Another cause for decompression sickness is diving too long or too deep as more gas is absorbed into body tissue and in higher concentrations than normal.

Ascent to an altitude in the case of divers flying shortly after diving too can cause decompression illness as pressure in aircraft cabins is not actually maintained at sea-level pressure the change in pressure can cause bubbles to form in the body.

More about- Signs and Symptoms of Decompression Sickness, First Aid and Treatment for Decompression Sickness, Prevention and Avoiding Decompression Sickness in Decompression Sickness: All About Scuba Diving & The Bends (Part-2)

* Photo Credits: photos by ParaScubaSailor, chris5aw, ClifB on flickr

Up until a few years back diabetes was one of the illnesses listed keeping potential divers from donning wetsuits and taking a plunge into the deep blue. Recently however, studies are showing that diabetes doesn’t necessarily mean ‘No’ Scuba diving and more and more cases of people with the condition diving are coming up. Of the total population in the United States as of 2007- 7.8% or 23.6 million people have diabetes. However with a proper medical examination, knowledge of possible implications and with due caution people with diabetes can indeed take up Scuba diving which with open the doors to a whole new world underwater.

(*Photo by- Ilse Reijs en Jan-Noud Hutten on flickr)

Determining the Type of Diabetes: Diabetes has two classifications: Type I, which requires insulin injections to control blood sugar levels and Type II, which doesn’t require the injections is often a case of obesity. Type II diabetes can be successfully managed with weight control, proper diet, exercise and, if necessary, medications other than insulin.

Diabetic patients run the risk of suffering excessively high blood sugar which is called hyperglycemia, or very low blood sugar, called hypoglycemia. The fact that if a diver suffers a hypoglycemic attack when under water, the symptoms such as confusion, sweating, rapid heartbeat and unconsciousness could easily result in death. This is the main reason as to why diving with diabetes is risky.

There isn’t much information available regarding specific medications and diving, but generally, dive medicine professionals haven’t found any scientific data to suggest these medications cause any problems under pressure. But it’s best to find out about any side effects the medicines may have that may affect the persons functioning.

Diving with Diabetes: If a diabetic persons fitness is monitored and they are very rarely hypoglycemic, with the following assessment and extra caution they maybe cleared to dive safely.

For one, it must be established by a doctor familiar with diving that the person’s blood sugar levels are stable after doing moderate exercise like jogging and swimming which he/she is likely to exert when Scuba diving and carrying Scuba gear and equipment. Assuming with the physical activities test no hypoglycemia occurred, the person can start diving in a controlled environment and closely monitored before moving to calm open-waters.

What To Do When Diving with Diabetes:

• Inform your dive buddy as well as dive leader about your condition in case of an emergency.
• Monitor your blood glucose levels throughout the day of a dive. This should be check right up until the dive and if the blood sugar levels are even slightly lower or higher than normal, avoid the dive.
• Carry and keep handy any medicine or insulin injections on the dive boat.
• Keep hydrated by drinking lots of water before and after the dive.
• Keep foods like candy bars, oral glucose drinks etc. on the dive boat.
• Log all blood glucose level results and necessary information in your dive log book.

What Not To Do When Diving with Diabetes:

• Never dive in buddy pairs with two diabetic divers. One member should not suffer from diabetes.
• Avoid deep dives greater than 100ft (30m). On deep dives, hypoglycemia can be potentially mistaken for nitrogen narcosis and ignored which is too big a risk too take.
• Don’t dive for long stretches at a time. It’s best to break up your diving into two dives and check your blood sugar levels in between dives, than dive for longer than 60 mins.
• Avoid cave diving and other enclosed forms of diving.
• Don’t dive if your medical treatment has been changed. This includes starting, stopping, change in medicines or simply adjusting the dosage.

Taking all things into consideration, if a person with diabetes wishes to dive then approval of his physician or the diabetic clinic which he attends should be filled out deeming the person fit to Scuba dive. At the end of the day it’s a choice and the diabetic diver should be responsible to be aware of the risks he goes through by diving with diabetes.

Whether you’re a rookie diver or a seasoned pro it’s good to know the do’s and don’ts of dive boat etiquette to preserve order and just get along when diving in groups, especially when you don’t know one another. In case you missed our last post for the first 5 tips on dive boat etiquette you can catch it here- Dive Boat Etiquette- For Pro’s and Rookies Alike. Here’s a continuation of the article with some tips on post dive do’s and don’ts while boat diving.

(*Photo by-  DanTheBeastMan on flickr)

6.  Rinsing off
Don’t use the fresh water shower to rinse off your Scuba equipment. The showers are meant for you and not dive gear. You’re gear will not get spoilt in the time it takes you to get back to shore to rinse it off or till you get home. Also, don’t rinse your Scuba mask or small items in the camera storage. It may just be a mask, but you’re not supposed to do that- it’s for cameras only. If you are rinsing yourself, off make it quick and don’t take your own sweet time while others are hopping around the deck because they are cold waiting while you shower. Step to the side while rinsing off and spray over the edge of the boat – not into the boat or anyone on the boat.

7.  Store your Scuba gear back and don’t leave stuff lying around
When you first hand your fins over at the swim-step, the crew or dive master puts it down by on the deck. Don’t forget to pick them up so that they don’t collect in a pile by the step and trip anyone. Put back all your equipment in your Scuba gear bag in between dives and not lying around on the deck. Use the same Scuba tank space allotted to you when you started and don’t just plop your stuff down where someone else was seated. Wetsuit divers, never leave your wetsuits on the benches. If you’re taking it off stash it with the rest of your wet gear and don’t attempt to dry it on the boat. If you prefer to keep wearing it, carry an extra rag or towel to mop up puddles you’ll leave where you sit. (*Photo by-  star5112 on flickr)

8.  Keep the dry spaces dry
Dry storage real estate on a dive boat is very precious. It’s meant to keep things like your towels, cell phones, wallets and other small necessaries, not your Scuba regulators or other dive gear which is made to get wet, no matter how precious to you. Don’t drip wearing your wetsuit over the dry bin either.

9.  If you get seasick
There’s no shame in getting sea sick. It happens to everyone once in a while, just, don’t make a mess. Carry seasickness pills with you or a piece of ginger root. If you do feel your last meal making an unpleasant appearance lean over the lee (wind at your back) side of the boat to do your business.Try hard not throw up where scuba divers will be, like off of the back of the boat or definitely not in the boat. Don’t use the bathroom or ‘head’ to hurl for a number of reasons. One, the confined space and lack or air circulation will make you feel even more sick than before and two, it’ll simply make the people who need to use the ‘head’ just as sick. (*photo by- Capt Kim on flickr)

10.  Using the head
When there is a toilet or ‘head’ as it’s called on a boat, it needs to be used for liquid emergencies only. Anything else is best done before or after your boat trip, unless it’s an extreme emergency. On most boats, the head is where the shower is. In this case avoid getting everything from the toilet seat, toilet paper, walls, ceiling, sink and so on wet when you are rinsing off. Don’t clog the drains and if you notice them clogging up inform the crew, don’t ignore it.

**Additional tip: Respect the crew. They introduce themselves before the trip and it’s always nice to try and remember their names and show them courtesy. The crew helps you out a ton on board, tip them generously for their service.

Following these ‘rules of thumbs’ when it comes to boat diving can come a long way in enjoying your trip. A little consideration and responsibility can go a long way in making Scuba diving from a crowded boat better organized and overall a lot more enjoyable.

Also Read: Dive Boat Etiquette- For Pro’s and Rookies Alike

Scuba Diving and Boats are an obvious match. With the just the feel of being at sea, cool sea breeze in your hair and the excitement of the dive, it’s all part of the sensory experience that is boat diving. However, you are almost never alone when in a dive boat. Boat diving is a great way to meet other divers with various experience levels but along with it comes an unspoken code of conduct.

You would think more experienced divers should know all of these pet peeves and make for pleasant company on the dive boat, but very often it’s the experienced diver that’s too smug to care or inconsiderate to other divers which really just ruins it for everyone. So whether you’re a rookie diver or a seasoned pro it’s good to know the do’s and don’ts of dive boat etiquette to preserve order and just get along when diving in groups, especially when you don’t know one another.

(*Photo by-  star5112 on flickr)

1. Never keep the boat waiting.
Always get to the dive boat early and load up your scuba gear well before time to leave. Arriving late is going to piss off a bunch of divers you don’t even know as yet and even getting there just on time is going to delay the boat from leaving until you and your equipment are all settled in.

2. Pack as compact as your can.
Use a Scuba gear bag and not a massive trunk size kit that takes up as much place as if your Scuba gear and equipment were scattered all over the deck. You want to pack all your gear as compact as you can to store it easily under the seat and not take up too much room. You have to remember that there are anywhere between 6-16 divers each with their 50lbs or more of dive gear on that dive boat, you need to be considerate about space which is a valuable commodity on dive boats.
(*Pictured above- Armor Amphibian Wet/Dry Mesh Gear Bag. Available at LeisurePro.com)

3. Check and assemble your dive gear on the way to the dive site.
Keep all your scuba equipment and gear centralized in one place on the dive boat. Work from your Scuba gear bag and don’t spread all your gear and equipment in a pile on the deck floor for someone to trip over. Assemble and check all your gear well before you reach the dive site and not once you arrive.The whole idea is to be ready to jump in once the boat stops at the dive site. Getting ready before you have to dive in also helps if there is a problem with your gear or if something has to be changed without holding up the others waiting their chance to jump in.

4. Pay attention to the dive briefing
No matter how many times you may have dived the same site or heard other dive briefs there is no way you know everything there is to know about it. Dive site conditions change from time to time, currents, water temperature ans what you may see there and not to mention there are others on the boat who have never dived the site before and are actually listening to the dive master and his instructions. So keep your mouth shut and your ears open during the brief, chit-chatting while someone is talking is not only rude but makes you look incredibly stupid. (*Photo by- Lars Plougmann on flickr)

5. When it’s your turn, be quick.
When you get in line for the gate you better be ready. Don’t dilly-dally at the gate. While you’re zipping up your wetsuit, opening your Scuba tank valves, adjusting straps and what not, you’re blocking the gate for someone who was smart enough to get all geared up while on the bench. Don’t put your fins on at the bench though and Donald Duck to the gate. If you can’t put your fins on standing up, be the last in line so you don’t shuffle across to the gate stepping on everyone’s feet to the gate.

Continued in.. Post Dive: Dive Boat Etiquette

In order to successfully complete any Scuba Diving training, a student receives what is called a C-Card or a Certification Card. This card acts like a license to dive and all dive shops are required to  ask to see this card before renting out any dive gear and equipment. As a sport recreational scuba diving doesn’t have any one centralized certifying or regulatory agency, but is mostly self regulated. There are, however, several large diving organizations that train and certify divers and dive instructors and have become recognized certification agencies of the sport the world over, which most dive outlets and dive shops consider proof of proper scuba training.

These agencies work by training and certifying instructors in their syllabus and teaching methods, and then allowing those instructors to certify individual divers. In addition to providing all levels of diver training, the agencies also regulate the sport as a whole and represent diving professionals such as dive masters, dive instructors and dive operators. They widely participate in researching dive medicine, promoting marine conservation as well as marketing diving as a sport.

At a beginner level, the certification agency doesn’t play too much of an importance as the courses they offer as more or less similar courses and any main agency will be recognized by dive operators anywhere in the world. Right up to the professional level training the agencies recognize each others qualifications for recreational diving. However, when it comes to diving professionally they may not recognize each others qualifications.

When you first start off diving, you need to consider the instructors experience and the dive center offering up the course rather than letting the agency dictate your choice.

Here are the most recognized Scuba Certification agencies around the world today. Of these, PADI and NAUI are the most prevalent in the United States.

PADI- Professional Association of Diving Instructors
Based in the United States and by far by the biggest and most recognized dive certification agency in the world, PADI was started in 1966 to improve the training into a variety of different courses rather than just the one single universal course. prevalent at the time. PADI courses are very performance based dive programs. The introductory level emphasizes practical knowledge, safety and motor skills along with the foundations of diving physics, physiology and chemistry.

PADI centers are the most widely spread out across the world and you can find one in almost any dive destination. More beginner divers are certified by PADI than all other agencies combined. It has certified approximately 70% of divers in the United States and approximately 55% of divers worldwide.They are very active in promoting the sport and also in marine conservation through their Project AWARE operation.
Website: www.padi.com

NAUI- National Association of Underwater Instructors
Again a United States based agency, NAUI started in 1959 is the oldest recreational scuba certification agency. NAUI is a non-profit association which was started for the promotion of dive safety through education. Its diver courses are very similar to that conducted by PADI and SSI and it enjoys a status of being the second largest scuba certification agency after PADI.

NAUI boasts of a no. of celebrities and industry pioneers certified by them like Kevin Costner, Tiger Woods (NAUI divemaster member), Cameron Diaz, Jacques-Yves Cousteau (inventor of the aqualung) and many more. Many of whom have popularized the activity for NAUI. As of 1997 NAUI published standards for teaching technical diving as well.
Websites: www.naui.org

BSAC- British Sub Aqua Club
Founded in 1953 and based in the United Kingdom, BSAC is the largest dive club in the world. With over 50,000 members it has being recognized as the official governing body of recreational diving in the United Kingdom. BSAC operates through 1600 local independent dive clubs and over 400 diving schools world wide. Given that UK waters are relatively cold and have restricted visibility, BSAC training emphasis on rescue training very early in the programme.
Website: www.bsac.com

CMAS- Confédération Mondiale des Activités Subaquatiques/ The World Underwater Federation
CMAS is the international umbrella organization for diver training organizations. Founded in 1958, CMAS is based in France. The organization offers the international framework for diver and instructor qualifications and members of the CMAS Council are representatives of the other recognized dive agencies.

The training philosophy of CMAS members originates from professional or military diving backgrounds and tends to reflect the full range of European and world diving standards.The difference in the philosophy for diving between CMAS and US-originated dive education is very distinct as their ideology is entirely about quality education over profit, which accounts for its courses being taught worldwide in more dive schools than dive shops.
Website: www.cmas2000.org

SSI- Scuba Schools International
With 35 Regional Centers and Area Offices around the globe, the 1970 established SSI is based in the United States. It has well over 2,200 authorized dealers and supports Dive Businesses and Dive Resorts. A major difference between SSI and other diver education organizations like PADI, NAUI, CMAS and others is that SSI is a Retail based organization, intended to ensure the quality of training worldwide.
Website: www.divessi.com

Other Agencies
IDEA- The International Diving Educators Association (www.idea-scubadiving.com)
ACUC- The American Canadian Underwater Certifications (www.acuc.es)
PDIC- The Professional Diving Instructors Corporation ( www.pdic-intl.com)
SDI/TDI- The Scuba Divers International/Technical Divers International (www.tdisdi.com)

To Shop for Scuba Diving Equipment and Gear visit LeisurePro.com – The Diver’s Emporium

Many people are unsure about Scuba Diving and claim with certainty that they would never try it. Ask them why? and one of the most common replies is ‘Are you kidding? I’ve seen the movie Jaws!’. So is this fear of sharks and Scuba diving justified?

(*Photo by SF Brit on flickr)

Well, we’d be lying if we said that the chances of seeing and encountering a shark was low or even non existent. Let’s face it, you dive in open waters and as the biggest predators in the ocean, there are over 400 different species of sharks. However, hundreds of thousands of divers encounter them on dives across the world and that’s not counting the daredevil kind who specifically go shark diving wanting to cross it off their ‘list of things to do before I die’ and they don’t become shark bait.

Contrary to popular belief, Jaws and the endless shark attack programs shown on TV, there have been very few shark attacks on Scuba divers.  Let’s just say your chances of getting hit by lightning, dying of a wasp, bee or snake bite are a lot more than becoming a shark’s supper. In the United States the annual risk of death from lightning is 30 times greater than that from shark attack. (*Photo by manoellemos on flickr)

If you think about it logically, Sharks just like most animals are weary of foreign objects (read as humans in the ocean!). Look at it from a shark’s point of view- if you came across a noisy bubble blowing, large strange shaped  creature carrying Scuba gear and equipment on their backs that often flashes bright lights (with dive flashlights or underwater cameras) and not to mention in groups or at least more than one, would you stick around to figure whether they would harm you? If you’re still thinking, the answer is No.

Worldwide there have been probably 70-100 shark attacks annually resulting in about 5-15 deaths as compared to the millions of dives conducted each each. Of these the Scuba diving related shark attack percentage is very low. The majority of this unfortunate incidents occurred to surfers, swimmers, skin divers, kayakers while swimming or surfing in near shore waters. In most instances, these probably are cases of mistaken identity that occur under conditions of poor water visibility and not an intentional to feed on the human. The victim seldom sees its attacker and the shark does not return after inflicting a single bite or slash wound as it soon realizes that it isn’t it’s usual prey.

As bad as a Shark taking a nip at you may sound and with no intention of downplaying the severity of the situation, the shark attack trauma is less common than such beach-related injuries as spinal damage, dehydration, jellyfish and stingray stings and sunburn.

A few stats on your odds of being attacked according to the Florida Museum of Natural History based on data from 68 ocean lifeguard agencies within jurisdiction is
Drowning and other beach-related fatalities - 1 in 2 million
Drowning fatalities -  1 in 3.5 million
Shark attacks -  1 in 11.5 million
Shark attack fatalities - 0 in 264.1 million
(*Photo by c.lathe on flickr)

At first many divers find the thought of sharks quite disturbing mostly cause they tend to have a certain presence that you can’t quite trust. But if you do get the pleasure (yes, it is exhilarating to be in the presence of such a creature) of seeing one, you will find that they tend to be more afraid of you than you of them with the exception of a few types (namely- the Great White Shark, Tiger Sharks and Bull Sharks). Sharks are definitely not the evil monsters that you see on TV. They truly are very misunderstood.

If this is still the only unnerving fear you have of Scuba diving, the best and only way of overcoming it is facing it head on. Only by experience will you get over your fears and it won’t take you long to wish you spot a harmless shark on a dive.

For those divers who still get the jitters when they hear the word Shark, look out for our Tips on How to React in the presence of a Shark. (*Photo by StormyDog on flickr)