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Tech Skills on the Kinghorn January 31, 2009

Posted by Chris Sullivan in Dive Log, Shipwrecks, Technical Diving, Training.
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The following day, on Sunday September 2nd 2007, we joined the recreational divers on the Kinghorn. We spent most of the time on the deck, going through our doff/don and shutdown skills. This time, I did not fail to add some air to my BC to aid in keeping my balance, and didn’t let the Scuba unit get too far from my centre of gravity. The shutdowns were even easier than the time before, and I could go through the whole sequence of shut down and opening of all three valves in less than a minute.

The next exercise was dropping and picking up stage bottles while swimming in one continuous movement. The first pickup was a little awkward with the speed of the current behind us but the second was great.

We also did our SAC check, swimming at a normal pace for 10 minutes back and forth on the wreck. In the current, the upstream legs were much slower than the downstream, but we kept the same pace the whole time to get a good idea of our air consumption.

In the 10 minutes, I used 250 PSI, while maintaining a depth of 80 feet. Calculating the SAC is relatively straightforward. The number of cubic feet consumed is simply the capacity of the tanks, multiplied by the PSI consumed, divided by the working pressure of the tanks. The tricky bit is that on most steel tanks, the working pressure isn’t the rated pressure, but the rated overpressure of the tanks. So instead of 2400 PSI I had to used 2400 plus 10% which is 2640 PSI.

Each tank holds 95 cubic feet at 2640 PSI, so from two tanks the air consumption was 2x95x250/2640 cubic feet. The result? Almost exactly 18 cubic feet consumed, or 1.8 cubic feet per minute. But that isn’t the SAC rate of course, because it hasn’t been adjusted for depth. To convert from air consumption at depth to air consumption at the surface, I need to divide the result by the number of absolute atmospheres of pressure at my depth of 80 feet.

To do this, I need to adjust the gauge pressure in atmospheres to absolute pressure. My gauge pressure was based on 80 FFW (feet of fresh water). You’ll see in the books that to convert feet of depth to absolute atmospheres you add 33 to the depth then divide by 33. That’s for salt water. For fresh water, it’s 34 feet. Now if you’re using a depth gauge or computer that’s set to salt water, you use the salt water formula as your depth reading will be slightly different from your actual depth.

So the pressure at 80 feet was (80+34)/34 atmospheres. That’s about 3.35 atmospheres. If I divide my air consumption at depth by the absolute pressure I get the SAC rate, which is about .54 cubic feet per minute. Not bad, although I think I used to do better when I was in my twenties.

For dive planning, we use SAC rates to estimate how much air we need, or more commonly, how much time we can safely spend underwater to follow the rule of thirds or whatever other measures we’re using. If I estimate my potential errors as depth +/- 1 foot, consumption +/- 25 PSI, tank capacity +/- 1/2 cubic foot, and time +/- 6 seconds then my maximum possible SAC rate is close to .6 cubic feet per minute. This is what I would use for dive planning, although SAC rate should be checked often, as it can vary with conditions, diver fitness, anxiety and so forth.

For your calculating pleasure I’ve constructed a simple spreadsheet using MS-Excel that estimates the SAC rate both using the standard formulas and worst case by taking measurement error into account.


The Lillie Parsons Drift Dive January 30, 2009

Posted by Chris Sullivan in Dive Log, Shipwrecks.
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On September 1, 2007, after practicing our technical skills on the Daryaw, drifting along the bottom of the St. Lawrence and then under our lift bags, the boat headed to Sparrow Island for a dive on the Lillie Parsons. We were supposed to sit this one out, as our tanks were nearly empty, but one of other divers had a partially full AL80 available, and as my Seaquest Raider could be converted to work with a single tank in fairly short order, I opted in to the dive.

One problem I had was weight – I didn’t have my usual weights with me because when diving with the steel tanks I didn’t need any. My ankle weights were still in my bag though so I stuffed them into my BC pockets and dived with only 3 pounds.

The entry to the Lillie is good fun. A good boat captain (like ours, who is old enough to have seen the Daryaw sink in 1941) will tie off about 100 yards upriver from the island with the bow facing the current, and the divers jump off one by one and drift along the surface to the island, being careful to position themselves at the point where the are no strong currents going to either side of the island. You then descend swimming back up the river and moving to the right (or North) to go down the wall on to the wreck which is upside down and barely hanging on to the slope. It is slowly slipping down and eventually will be a technical dive on the bottom at 165 feet.

I’ve seen a number of attempts at different ways to get on the wreck. Another one that works is to follow the anchor chain from the island down to the wreck, but I’ve not tried this personally. We saw one boat parked where we usually do, but the divers submerged under the boat instead of drifting down to the island. We saw bubbles in the vicinity of the boat for 15 minutes or so, and I don’t know if they ever found the wreck. Another group tried to drop down from beside the wreck and missed it completely.

There’s few things to see on this upside down wreck. The mast is visible, but it’s a hull, after all, and there’s not much to explore. Penetration is possible, but it’s confined and I don’t want to be in it when it finally plunges to the bottom. If you expend the effort to swim to the stern, which points into the current, you can fly over the hull which is always fun. This web site provides a good description of the wreck itself.

The current moves briskly and in most places you need to hang on to something unless you keep down between the wall and the wreck, in which case you’ll mostly be in eddies. After seeing all there is to see, you just let go and enjoy the drift. On the satellite photo below, the entry point is down at the bottom left, and the end of the drift is to the middle left. It goes by very fast! We drifted at about 30 feet, as the line hanging down from the island only goes to about 40 feet to discourage people from going to deep.

All of our divers found the wreck, and drifted together catching the line. It’s not hard, but you have to stay close to the wall or you’ll miss it. My maximum depth on the wreck was 56 feet, an the dive was only 18 minutes so even though I started with only 1800 PSI I came out with 800. Brad noticed I was lightly weighted because he saw me descend inverted with my fins sticking up out of the water. Even on ascent though, with a couple of pounds less air on my back,  I had no trouble holding my depth on the safety stop.

Plunging into the Tec Deep Diver Course January 29, 2009

Posted by Chris Sullivan in Dive Log, Technical Diving.
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The dive club’s annual Labour Day weekend in Brockville was the final stage of my technical diving course. There were 3 students on the dives – Dave, Pete and me. Dave was already a technical diver with another agency, IANTD I think, Pete was a Divemaster, and I was working on it. I still didn’t have a technical BC, but the Seaquest Raider was adequate for the dives we were doing with 50lb of lift and the ability to accommodate doubles. One thing it lacked was a double bladder (it has the capability as an option), which can be a problem if it fails, as the only weights I was using were my tanks. Needless to say, dropping your air supply on a deep decompression dive in order to become buoyant can be hazardous to your health. I had to rely on my lift bag as a backup, but I feel safer now that I have real double-bladder wings and a backplate.

In July, when in Brockville for the wreck diving course, my last dive was on the Daryaw, and this was the first dive of this trip. The Henry C. Daryaw is close to the Canadian side of the river and rests upside down in about 100 feet of water. The centre section is raised from the bottom and provides convenient shelter for doing training exercises, so we headed down the line, doing bubble checks along the way, and settled in a ring around Brad to practice our skills at a maximum depth of 98 feet.

The first skill was valve shutdowns. After not being able to reach my valves in my dry suit I was pleased to find that I could get to them in my wet suit, although with some difficulty. The doff/don of the Scuba unit exercise, while in my 3mm wet suit was  much better than my struggles in a buoyant dry suit, didn’t go that well. I was quite negatively buoyant while kneeling on the bottom, and lost my balance when I took the it off my shoulders. I eventually got it back on but I was glad noone was filming me. We also dropped and picked-up stage bottles which wasn’t a problem. The Raider has nice big D rings that are easy to locate and clip. I find my OMS IQ pack more difficult to clip to, as the bottom rings are further back.

I learned something from Dave on that dive. His doff/don procedure kept some of the weight of the BC on his right shoulder, which helps a lot with the balance. While I thought that might count as cheating, I did it the same way after that, and never lost my balance again. I also remembered to add a little air so the Scuba unit would be less negative and easier to handle.

After the skills practice we swam out of the wreck and into the strong current of the St. Lawrence River. We drifted along the bottom for a few minutes, then deployed our lift bags and ascended to our decompression stops. While Dave and Brad were using Cochran computers, Pete and I had the Apeks Quantum which is a lot more conservative. I could see the impatience building as we waited and waited for our computers to clear. My joke for the rest of the weekend was that divers with Cochran computers tolerated bubbles better than us Quantum users, because they didn’t need decompression stops and we did. I did read a review of the Quantum compared to the Cochran Commander which didn’t have the same degree of difference between the deco times as our experience showed.

After a nearly perfect dive, while we were waiting for the boat to come and pick us up I made my biggest error. I was holding the lift bag in one hand and the reel in the other when I dropped the reel. All 50 metres of line spooled out as it sank to the bottom. We retrieved it but I had a real tangled mess to deal with, and had to face the teasing of my fellow divers back on the boat.

Total dive time was 1 hour and 2 minutes. The water temperature was a balmy 22C (72F) which was just fine in my 3mm wet suit without a hood, especially as we were either protected from the current or drifting along with it for almost the entire dive.

Night Diving at Big Bay Point January 28, 2009

Posted by Chris Sullivan in Dive Log, Technical Diving, Training.
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It was August 23rd, 2007, a week before the Brockville Labour Day dive weekend when a bunch of us set out to do some technical diving practice at Big Bay Point, located on the south side of the mouth of Kempenfelt Bay in Lake Simcoe. Three members of my technical diving class, Dave, Pete and Brian, and I headed out with Brad just after 8pm. Being late August, the days were getting shorter quite quickly and it was twilight when we finally splashed in. Also, in all my 25 years of diving I had only done 2 night dives, so we used this as an opportunity to work on my night diving specialty as well.

If training for technical diving is difficult in the daytime there, it was doubly hard at night, especially with the don/doff exercise. I still hadn’t purchased a wet suit any thicker than my 3mm tropical suit, and while I probably could have put up with the 19C (66F) temperatures if I had been wearing a hood, I had decided to use my dry suit (and a hood for some strange reason). I was still using my fancy Seaquest Raider weight integrated BC which accommodates doubles but no backplate, and while I had zero weight in the pouches and relied only on the weight of my doubles, doff/don was a little crazy. Once you take the weight of the scuba unit off your shoulders, the dry suit tries to rocket you to the surface, while the scuba unit wants to bury itself in the silt. Getting it back on is a wriggling silt-fest that never looks elegant.

I still couldn’t reach the valves, which worried me a lot. I felt that it wasn’t worth being a certified technical diver if I couldn’t do this without adding slob knobs to my tanks and manifold. The remainder of the technical course was done in a wet suit so it didn’t turn out to be a problem, and in early 2008 I practiced with my new OMS backplate system and figured out how to do it. Even so, I still do stretching exercises several times a week to maintain the flexibility to reach them.

I was watching The Sea Hunters yesterday, which if you’re not familiar is a fairly recent TV show produced with a lot of Canadian Government funding feature author Clive Cussler, James Delgado who is the Executive Director of the Vancouver Maritime Museum, and the father and son team of Mike and Warren Fletcher, who are the lead divers and underwater cinematographers. Mike and Warren are also part of the series Dreamwrecks but I don’t like that show nearly as much. This episode featured rebreathers, trimix, doubles, accelerated decompression, surface supplied breathing mix, sidescan sonar, a Russian-made equivalent to a Haskel pump not to mention some really good diving sequences going down to 200 feet or so.

I only mention this in reference to reaching my valves. At one point in the show, James Delgado’s LP hose to his primary regulator, which was configured into his full face mask (the water temperature was near freezing) exploded before the dive. They voiceover mentioned that if this had happened underwater, he would have had to find one of the other divers to help him shut down the valve and also face the problem of switching to a backup reg after flooding the mask. This must mean he was unable, in his dry suit, to reach the valves himself – so I don’t feel so bad now about having difficulty. I do wonder why he would put himself in the dangerous situation of doing a deep decompression dive without being able to manage his own gas supply.

We also practiced dropping deco bottles and picking them up again. With the small steel tanks we were using this wasn’t hard. Because they’re quite negatively buoyant, you have to add air to the BC when you pick them up or you’ll find yourself getting acquainted with the bottom, and even more important dump air when you drop them.

After doing all this practice for a while we ended up losing each other so after a few minutes on the surface I swam to shallower water and did solo practice with my lift bag. This worked pretty well also, although it took longer than it should have. After just over an hour in the water and 47 minutes submerged, we call it a night and headed home. I’d used 1100 PSI in my Faber 95 doubles, which is a lot for that depth and bottom time but I bet I used half of it doing the doff/don exercise in my bulky dry suit.

Divers or Drivers? January 27, 2009

Posted by Chris Sullivan in Miscellany.
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Although most of the time we spent more time getting to and from the dive site than under the water, this is going too far. While the second day of the EFR course was underway, Brad came in with a box of T-shirts for this year’s pro divers. This year’s colour was red with white lettering. However there was a slight problem with the message on the back.


When Brad told the supplier he immediately offered the shirts at half price, but the idea of wearing the shirts  is for the students to easily recognize the instructors and divemasters at the dive site, and this just misses the mark.

Last year’s shirt was a nice purple with yellow lettering, and printed correctly. Such are the trials of running a small business, both as a seller and as a buyer. This year’s shirts will likely end up with a white rectangle on the back with red lettering.


EFR Instructor Course Day 2 January 26, 2009

Posted by Chris Sullivan in Emergencies, Training.
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On Sunday, we finished our EFRI course with the exam and two skill presentations and demonstrations. On the test I got 58/61, passing grade was 75%. Of the three I got wrong, one was because I answered the question the way I thought it was leading rather than what I thought was correct. Another was a bit of trick question but I understand the reasoning, and the third was because I read the question incorrectly. So not too bad although I strive for perfection.

The skill presentations were lots of fun, and in the cold temperature of the dive shop (around 15C) moving around a bit is a welcome relief from sitting in the classroom. The class acted up a bit, including an extreme method of immobilizing the victim’s head in the case of a spinal injury as you can see below.

A little close for comfort

A little close for comfort

My first demonstration was AED use, which I’d never done before, so it was good practice for me. The Red Cross course I took 3 years ago didn’t cover it, and the St. John’s Ambulance course last year didn’t include any practice although it briefly went over it’s use. Neither of those courses involved the application of Oxygen so this is an additional feature of EFR.

Each demonstration then involves watching a student repeat the demonstration. Matt was my student, and did everything correctly except he plugged in the pads and stuck them on the victim’s (a mannequin) chest before turning on the AED to follow the instructions.

The second demonstration was primary assessment for children, which varies from the adult procedure in that if the rescuer is alone and there is no knowledge of a preexisting heart condition in the victim, breathing and circulation is checked and attended to prior to alerting EMS, presumably because the likelihood of cardiac arrest is much lower in children. Other differences are that special pads and cables are often available for Automatic External Defibrillators, and that more care needs to be taken when tilting an infant’s head back to open the airway.

Steve demonstrating an incorrect procedure

Steve demonstrating an incorrect procedure

By 2pm we had our completed forms to mail in to EFR, along with the registration fee. Now we are qualified we can list ourselves on the EFR web site as qualified instructors. I’ll likely teach some of my coworkers and at the shop if asked. The shop now has several new EFR instructors, all of whom will be trying to become Open Water Scuba Instructors at the beginning of the summer dive season. One of the best things about being an instructor is that I don’t have to recertify every two years to maintain my pro diving qualification.

Scuba Diving on the Joseph C. Morrison January 25, 2009

Posted by Chris Sullivan in Dive Log, Shipwrecks.
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Diving this wreck was long overdue for me. The Morrison is the closest real shipwreck to my house. It’s an easy shore dive in Lake Simcoe about 50 minutes drive from my home, although it’s a good way off shore and traditionally swum underwater. Depth is about 30 feet, which is about double the usual visibility, and with the wreck fairly broken up it can be hard to find all the bits.

Lake Simcoe’s tour boat industry in the 19th century has quite a colourful history. It used to be cottage country for the city of Toronto, and for some it still is, although that function has expanded greatly into much more distant locations. The Morrison is one of many “side wheelers” that plied the waters from town to town on the lake. One night in August 1857, while docked in Barrie, Ontario, the Morrison caught fire and burned to the waterline – with passengers who were sleeping on the ship fleeing for their lives. Fortunately there were no fatalities. It drifted offshore and sank. Parts of the wreck was salvaged shortly thereafter, and the remainder lay there until being discovered by divers in 1974.

It is now the most popular wreck dive in the Lake. I was pleased to note that my dive on August 16, 2007 was exactly 150 years and 12 days after it sank. Several members of the club met that evening, and my buddy Kelly, who was also acting as Divemaster (she was also a Divemaster candidate) and doing a fine job at it, entered the water at 7:30Pm and followed the line out to the wreck.

Clad in a 3mm wet suit with gloves but no hood, I’m surprised I spent a whole 39 minutes in the 17C (63F) water. It was quite chilly. In my technical training I was practicing the frog kick and still wasn’t going to fast with it, but Kelly had trouble keeping up likely because she was pulling the dive flag on a float behind it.

I’ve done the dive a couple of times since and its main claim to worth is it’s proximity to my home, but there’s a boiler to see, and if you look around a bit, you can find the wheel, although I didn’t see on this dive.

Unfortunately I lost another piece of equipment on the dive – a nice UK C8 dive light. I couldn’t figure out how I did it, but when I got home it wasn’t in my car and I never saw it again. Two dives, and I’d lost a light, a pair of gloves, and a hood. Not good,  but after that I got much more careful in keeping track of my stuff.

Here’s the text of an article in the Oswego Daily Journal from what looks like May 2, 1855 talking about the launching of the Morrison, which somewhat contradicts the account from the other link in this post which states the Morrison was “just 3 years old when it sank”, although perhaps the latter article meant 3 years sincel the hull was laid down, and not since the launching. Two other things I also note from the article are (1) that the launching of a ship in Lake Simcoe would hold enough interest to readers in far away Oswego New York to be published, and (2) that the article implies that in early May the lake had only just become free of ice, which is much later in the season than it clears these days!

“The Toronto Colonist says Lake Simcoe is now entirely free from ice. The steamer Joseph C. Morrison in rapidly approaching completion, and will be ready for the summer travel. In the mean time, the steamer Morning will run from Bell Ewart to Orillia—and upon the completion of the new steamer, we understand she will be employed carrying freight and towing. The hull of the Joseph C. Morrison was built under the superintendence of Capt. Chisholm, and the upper work is being proceeded with under Mr. Porter, the company’s superintendent of repairs. The engine and boiler were built by Gartshore & Co., Dundas.  The fitting up, which will be of the most elegant description, has been entrusted to Messrs. Jacques and Hay, of the city. She will be under the command of Capt. Fellows, who, we are sure will be very popu!ar.”

Emergency First Response Instructor Course January 25, 2009

Posted by Chris Sullivan in Emergencies, Training.
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One of the prerequisites for becoming a PADI Open Water Instructor is to become an Emergency First Response Instructor. Emergency First Response Corporation is run by Drew Richardson, who also runs PADI, and this prerequisite was introduced in 2009. There are 3 variants of the course: Adult Primary Care; Adult Primary and Secondary Care; and Child Primary and Secondary Care. Both adult and child care can be taught in the same course.

Like PADI courses, the EFR instructional materials are well laid out and cover the essentials without much extraneous information. It is based on prescriptive learning, with the opportunity to do reading, watching videos or both prior to the classroom portion so that the student can focus on skills practice and scenario training in class.

While the course materials tell us that renewal into teaching status requires that you certify at least one student between renewals, the instructor told us that was no longer necessary. This might be an outcome of the  new mandatory prerequisite for Open Water Scuba Instructors, as many instructors may not have the inclination or opportunity to teach EFR, or may be acting as guides and not even teach Scuba.

Today’s class had a fair bit of presentation, on setting up the classroom, materials required and course marketing, but I also had to demonstrate one of the Primary Care Skills (that’s the emergency stuff, as opposed to splinting and dressing wounds). Mine turned out to be CPR, i.e. artificial respiration and chest compressions – so while my classmates Steve, Matt, Marty and Jim all had mini-lectures, I had to do a full demonstration on a mannequin. It was good to go through it for my own practice, and I found out that mannequin technology has improved.

This one featured a special bag that runs from the mouth to the lungs, good for a single class, so that the mannequin itself only requires superficial cleaning after class. It also made a satisfying click sound when the chest is depressed sufficiently, and has a series of light emitting diodes that glow a satisfying green when the rate of compressions is sufficient (i.e. 100 per minute). For $180 it seems like a good deal.

I took a nice picture of the class in action on my Blackberry but couldn’t transfer to my laptop. The file seemed to move OK but the computer doesn’t recognize the file format.

Speaking of CPR, some good news. I wrote some time ago about an incident after the dive club holiday party where one of the assistant instructors (and I found out later a divemaster as well) gave CPR to a heart attack victim. It turns out the man lived after all. Dave and Pete gave the guy CPR, then the paramedics arrived with a defibrillator and told them it wasn’t working. They took him to the hospital and apparently the man’s heart had to be restarted 3 times, but he finally made it. I’m glad to report this as I’ve read about a lot of incidents where CPR has been given where the victim died anyway.

Tomorrow, we practice skills practice – diagnosing where students make mistakes and correcting them in an appropriately positive manner. Then the final exam and we can send in our applications for instructor certification.

Canada’s National Film Board January 23, 2009

Posted by Chris Sullivan in Diving Books and Films.
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2 days ago the National Film Board of Canada made 700 titles available through streaming video (and some, if not all for sale on DVD) across a wide range of topics and dating from the inception of the institution in 1939 to the present. Initially formed to support the war effort, the Film Board went on to gain an international reputation for creativity in animation, documentaries and other forms of Cinema with a strong emphasis on Canadian history, commerce, environment and geography.

There are two connections I can make to the topic of this blog. The first is that there are many films that include diving or underwater topics, including two that are collaborations with Jacques-Yves Cousteau, neither of which are listed in the Wikipedia film credits of Cousteau. The first film I noticed using a search feature called “Getting Around” featuring air travel, scuba diving (Cape Breton’s Dolphin Skin Diving Club) and canoeing. There were some stills of the Scuba Diving sequence on the site, though, like the one above.

The second connection is that while my wife and I were on our first visit to Cuba we became acquainted with Sydney C. Newman, who worked for the Film Board during World War II and was its Chairman from 1970 until 1975. He was also responsible for the creation of the BBC series Dr. Who and The Avengers, two of my favourite TV shows as a child. I still clearly remember seeing the first Dr. Who episode in the early sixties, although while the show has continued for decades, I am no longer a fan. As for The Avengers, I’m afraid that Uma Thurman has forever ruined my admiration for Mrs. Peel.

Mr. Newman, born in 1917, was quiet old by that time and hadn’t taken good care of himself. His wife had died in 1981 and he was travelling with a woman we suspected was a paid companion. She was a very tolerant person as he was a feisty old character, but was an interesting personality and great to talk to. He greatly admired my wife’s backstroke while we exercised in the pool, and given his advanced years I did mind at all. I’m glad I didn’t know the full extent of his celebrity at the time, as it would probably have spoiled things. My wife had also just finished the book A Good Man in Africa by William Boyd and recommended it to him, and he finally read it after his companion had also read and recommended it. He passed away in 1997 of a heart attack.

Some NFB films that are available on the site that might be interesting to divers are:

I haven’t watched any of these yet, but when I do there’ll be reviews posted here. Right now I’m still trying to catch up with all the TED videos I’ve downloaded into iTunes, and I still have a couple of months to go before doing that.

The Film Board is going to add 100 more titles to the collection within the next 6 months, that will make 800 of their 13,000 title library available. After that, they promise 10 per month. I wish they would go a little faster but I’m grateful for what they’re doing.

Scuba Divers Entering the Water January 22, 2009

Posted by Chris Sullivan in Training.
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In PADI training the most commonly taught method of entering the water is the giant stride entry. It is a good way to enter the water, but there are lots of others. I thought it might be a nice idea to make a list of all the ones I know for recreational diving. I’m sure the military has a bunch more for specialized use, like entering from a submarine or helicopter, or techniques for entering quietly. Commercial divers also have their own methods, like being dropped in the water by a crane, or on a mechanically lowered platform. I’ve heard the latter method is also available to recreational divers in some operations for people with disabilities or technical divers with huge loads of gear.

A few years back my brother gave me his old open water sport diver manual, published by Jeppesen. You may not have heard of Jeppesen, but I was familiar with them as the publisher of Aviation Charts in the United States. Originally published in 1975, this 4th edition published in 1984 is rather quaint, but has a lot of great information, including lots of information on fresh water fish identification. It covers several types of entry including Giant Stride, Forward Roll, Back Roll, Controlled Seated Entry, Step and Jump. The Jeppesen web site  has online aviation weather maps which are pretty interesting if you like that sort of thing.

  1. Giant Stride (a.k.a. Giant Step or just Step) – After all pre-dive checks, make sure BC is sufficiently inflated to float, mask is on and regulator is in the mouth. Place right hand on mask and regulator (base of hand on reg, fingertips on mask) to avoid them being dislodged on entry, while the other hand usually covers the gauge console or protects other vulnerable equipment like dive lights. Look down at where you will enter to make sure there is nothing and noone there, then look straight ahead. Then take a big step of the boat’s dive platform, the dock or the side of the swimming pool. Once you emerge from under the water in good condition, give an OK sign to whoever is looking out for you (usually from where you just came). Key points on this entry are not to jump, to look straight ahead, and to step far enough so the tank doesn’t hit the dive platform.
  2. Step – like a Giant Stride without the Giants. Just a step into the water. Jeppesen describes the Giant Stride differently to PADI, showing the diver with his arms outstretched to the sides and pointing upwards at a 45 degree angle. This is supposed to slow the diver down when entering shallow water, which it says is the main benefit of the Giant Stride. I think that PADI’s Giant Stride is actually more like Jeppesen’s Step. It’s a good thing that the Jeppesen Giant Stride is into shallow water because it would be easier to find your mask when it comes off.
  3. Jump – another one that I only saw in Jeppesen manual is sort of a kangaroo hop into the water. I’ve never seen anyone do it. I might try it for fun sometime when I’m not wearing doubles.
  4. Forward Roll – this one used to be more popular than it is now. It’s a similar setup to the Giant Stride but instead of a big step, you roll head first into the water. It was explained to me when I was taught this entry 26 years ago that if any equipment is going to get dislodged during the dive, it will probably happen while doing this entry. The only person I’ve seen doing it in the last few years is Philippe Kunz who runs Caicos Adventures on Provodenciales Island in the Turks and Caicos. If you try this one among strangers they might think you’re strange or don’t know what you’re doing.
  5. Backward Step – the only place I’ve seen this is on a documentary series by John Stoneman called the Last Frontier which was shot in the mid to late eighties. The divers (usually also wearing Speedos, which thankfully have disappeared along with hair bands and pleated pants) would turn around with their backs to the water and take a big backward step. In all other respects it seems similar to the Giant Stride but would seem to have an advantage for tank clearance, as it is now facing away from the boat.
  6. Back Roll – the coolest entry in my opinion, ideal for small boats but really lots of fun if you’re a long way from the water and wearing double tanks. When heavily weighted I seem to stay under water for a long time before bobbing to the surface. For a long time I thought this was the only way to enter the water as divers in the Cousteau documentaries always seemed to go in that way. Jeppesen criticises both the forward and back rolls for providing no protection against submerged objects. They have a point there, I think.
  7. Controlled Seated Entry – Sit down on the ledge, dock or poolside with feet in the water, reach to one side with both hands and turn around while letting yourself down. Easy, safe and quiet. I use this in the pool when the instructor is talking and I don’t want to cause a disturbance with a big splash.
  8. Shore entries – usually walking in with fins in hand, or when the surf is heavy walking in backwards with the fins on.

That’s my list. If someone knows more (other than backflips or faceplants that you see on youtube) let me know.