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Scuba Diving Gordo Banks, Los Cabos November 30, 2008

Posted by Chris Sullivan in Dive Log.
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Convincing our dive operator, Amigos Del Mar, to take us on the long boat ride to Gordo Banks took some time and money. We also needed to be able to show that we could dive, which I’d done in Los Cabos Bay, but this limited the number of customers to whom they could offer this trip, and thus made orgnanization that much more difficult.

Nevertheless, on July 20, 2006 (37 years after the Apollo 11 moon landing, which I remember watching on our old black and white TV when I lived in Ottawa), I found myself with 2 other divers, a guide and a boat captain speeding our way to the distant dive site. Gordo Banks is about 8 miles from shore, and rises to about 120 feet from the surface.  The weather was, as usual for the area, hot and sunny, at 90F (32C) during our dives.

Both dives were deep. The first was to 123 feet and lasted half an hour including the safety stop. We saw big schools of fish (Amberjacks) but the most memorable moment was to see the school of Hammerhead Sharks passing well above us. If they knew we were there, which is highly probable, they paid us no attention and were gone in no time. Unfortunately I didn’t have the presence of mind to attempt a photograph, nor did any of my other photographs of the dive turn out, due to the darkness. Some day I’ll get a decent underwater camera,, but meanwhile the silhouetted outlines of the 20 or so distinctively shaped creatures is firmly imprinted in my memory.

The water temperature near the surface was a bath-like 87F (31C), while at the maximum depth it was only 65F (18C). It was chilly in my 3mm wet suit. I’ve used that suit in 70F (21C) water without too much problem, but always worn a hood to keep my core temperature up. Fortunately by the time the safety stop was over I was quite warm again.

The second dive was to 112 feet, and was also about half an hour, this time with a 10 minute stop to wait for everyone’s computer to clear. Mine was done in a couple of minutes. While we were waiting I showed the guide/divemaster my SPG which was down to 500 PSI. He did the strangest thing, which was to pull his backup second stage out and offer it to me with incredible speed. At 100 feet, I would have appreciated the gesture (and be upset with myself for getting into that situation), but on a safety stop with a clear computer it seemed like overkill. One thing I did take away from the experience was to really be quick about providing air to an out-of-air diver, although I’ve never had to do that (low on air, yes).

There were schools of Amberjacks and Yellowfin Tuna all around (I was just reading that the Yellowfin Tuna population are endangered by the rise in the popularity of Sushi around the world). There were also a lot of Jellyfish floating around in the water, but none of us was harmed.

After the second dive and the long boat ride back, Carol, who owned a small villa about halfway between Cabo San Lucas and San Jose Del Cabo offered me a ride back to the resort, and ran out of gas along the way. A local gave us a tow (using an old rope) a couple of miles to the gas station and so about 4pm or so I was finally back at the hotel. Scuba diving is always an adventure, in and out of the water.

Scuba Diving in Cabo San Lucas November 29, 2008

Posted by Chris Sullivan in Dive Log.
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On my July 2006 trip to Los Cabos, the first diving was in the Los Cabos Bay – about a 5 minute boat ride. The site was very crowded with snorklers and divers,  which was strange as there didn’t seem to be very many dive operators in the town. The western side of the bay contains the famous Los Arcos, at Land’s End. My first impression of the dive was amazement. I’d heard very mixed reports about the diving in Los Cabos and was simply blown away by the quantity of marine life there. I’m more of a fish watcher than an appreciator of coral formations, and the size of the schools was like nothing I’d seen before. There is only one reef in the vicinity, and that is well east of Cabo San Lucas at Cabo Pulmo, so fish is what you go to see. The other unique thing was the water temperature, which ranged from slightly chilly to bath-like conditions. There was no thermocline like you find in summer in the Great Lakes, but in some places moving horizontally a few feet would bring about a dramatic change in temperature. I was glad for my full-length 3mm wet suit, even though it was alternately too much and not enough insulation. My computer recorded 76F (25C) on the first dive to 67 feet, and 84F (29C) on my second dive to 75. The first dive I’d done with no wet suit, but I had it with me, and wore it for the second. Obviously I had that backwards.

Starfish on my first diving day at Los Cabos

Starfish on my first diving day at Los Cabos

I had a photographic field day on these two dives. Fish were everywhere and were easy to shoot. The various puffer fish were my favourite. There were schools of them, or at least a bunch of them hanging out the same general area. They don’t all swim in the same direction, but they would swim in random directions in the same vicinity, so I think that’s as good a school as you can get with these fish. The Grouper and Napoleon Wrasses were just huge, and other species of fish would swim around in great numbers. I also saw Spotted Eagle Rays and Sea of Cortez Sting Rays all over the place, as well as Starfish and sea cucumbers.

Sea of Cortez Sting Ray

Sea of Cortez Sting Ray

In short there was plenty to see. More than I’ve seen since, even in Cozumel. If the diving weren’t so convenient in Cozumel compared to Cabo I’d always go there instead, but they just make it too easy in Cozumel.

Just too cute for words

Just too cute for words

Each dive was just a minute or two short of an hour, so I got my money’s worth. The area near Los Cabos is another of Cousteau’s top spots, and based on my experience there, it’s no wonder. It’s one of my favourite spots too.

Scuba Diving In Los Cabos, Mexico November 28, 2008

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A couple of days after my first dive of the IANTD Advanced Nitrox Course, my wife and I took a holiday to Los Cabos, at the tip of the Baja Peninsula in Mexico. The Peninsula divides the Sea of Cortez from the Pacific Ocean, and “Cabo” is a place where the cold currents mix with the warm water, which provides nutrients for the abundant sea life. It’s an old vacation spot, popular for Southern Californians around the time that pre-Castro Cuba was the tropical playground for East Coast Americans. The Peninsula is also the home for Baja 1000 road race, which I’d heard about for most of my life.

There were also some sad memories of the location. In the summer 1991, my parents, my two older brothers, and my oldest nephew travelled there to see the total eclipse of the Sun on July 11, at one of the best viewing locations. While I would have liked to have gone, the pressures of work were great and I decided not to go. A week before the trip, I was chatting to my dad and found it strange that he’d occasionally misuse a word, like he’d put the wrong word in a sentence and not notice. As he was one for having a few drinks, I really didn’t pay it any mind.

While they were away I got a call from my sister-in-law Sally saying that both my parents were very sick. They had to wait until their scheduled departure to head home because everything was booked solid. My dad lost both their tourist visas, and my brother had to bribe an official $20 US to let them get on the plane. Once they got home they were taken to the hospital where my father was diagnosed with Glioblastoma (a type of malignant brain tumour), and my mother with a serious lung condition. I forget her original diagnosis because it was wrong. It finally was called bronchiectasis, which is chronic, uncomfortable, but not fatal. He died on October 9th.

In his 3 months at the hospital, he would at various times make a certain amount of sense, although he never returned to complete lucidity. When my sister flew over from Australia to visit, the hospital staff gave him medication to temporarily shrink the tumour so he could sit up and chat, although without much of an idea of what he was talking about. As soon as she left, they took him off the meds and he was worse than ever. Meanwhile my mother had a lung operation to try and relieve her condition.

At one point my wife and I visited the hospital to see my dad in his room slowly dying and to see my mother connected to tubes and monitors in intensive care. My wife was so overwhelmed by the experience that as we were walking out of intensive care she fainted 3 times. A nurse helped her into a quiet room and went down to emergency to see a friend who was a physician and tell him my life was coming unglued. He was cheerfully signing some drunk drivers blood sample for a policeman, and his upbeat attitude helped a bit. He was talking to the cop about a Judge who had been murdered by a supposed male lover in a small town near Lake Erie, and it turned some of my friends knew the judge’s son, and I ended up meeting him as well a few years later. Small world.

So there I was almost exactly 15 years later in the same spot. My family had all stayed at the Hotel Finisterra in Cabo San Lucas, but that wasn’t available as a package deal so we ended up in San Jose Del Cabo at the Presidente Los Cabos. It was a really nice spot with the widest beach I’ve ever seen (and being from Australia, I’ve seen some wide beaches). The problem with the beach is that the strong currents are too dangerous for the beach to be open to swimmers. It was also the middle of summer, and it was really hot. The humidity was so low the cactus were dying, and the heat of the sun reminded me of the movies I’d seen where vultures circle overhead while someone is dying of thirst.

The only other problem with the hotel was that being in San Jose Del Cabo, for every dive I had to take a taxi to Cabo San Lucas, which took half an hour and 30 dollars. So it made the diving really expensive but the options I had to stay in Cabo San Lucas weren’t very good. I knew about the problem before I’d arrived as I’d made contact with the dive operator, Amigos Del Mar, before we left and they advised me to stay in Cabo San Lucas.

In view of the Turks & Caicos Islands trip the previous November, where I’d done 13 dives and a PADI Enriched Air Nitrox course in a single week, I made a pact with my wife to only dive on 3 days. Thanks to an American woman, Carol, who had her own place about 1/2 way between the two towns and convinced the dive operator to give us some variety, the 3 days of diving were in very different locations, so I saw a lot in those 3 days.

PADI Assistant Instructor Course – Group Photo November 27, 2008

Posted by Chris Sullivan in Dive Log, Training.
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Instructors, Assistant Instructor Candidates and Helpful Divemasters

Instructors, Assistant Instructor Candidates and Helpful Divemasters

As promised, here is a picture from last Sunday’s Assistant Instructor Training at Big Bay Point in Lake Simcoe. Notice that 3 divers were brave enough to go in wet suits. I’m in a sensible dry suit fourth from the left. I’ve now faxed the medical statement to my doctor and await his signoff, and for the pool session now postponed to mid-December. Hope to knock it off before year-end.

Pursuing the Shearwater Pursuit November 27, 2008

Posted by Chris Sullivan in Equipment.
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My dive shop is making it very difficult to choose anything but this computer for my next purchase. The computer is one of 4 of 5 candidate products that would work, but the company is willing to make our little shop the first dealer in Ontario, and being one of the dive pros, I would get a great first round discount for seeding the local market by wearing one on my wrist.

I also like the unit. For the money, it does everything I need, which right now is multi-gas, including trimix, and underwater manual gas switches. It can do rebreathers, but I won’t buy that model but upgrade if that becomes necessary some day. There’s no colour, no games, no RGBM, no air integration, or anything else fancy. It allows the diver to change the battery, which is great, and has an infrared interface to a Windows computer.

Speaking of RGBM, I’ve heard about all the great advantages and how it allows shorter deco times without bending divers and all that, but right now it all seems to be a kind of secret sauce. The papers that have been published by Bruce Weinke, the developer of the RGBM algorithm, introduce the concept and then seem to spend the rest of the time selling the idea. There’s no mathematical description of what the algorithm does, presumably to protect his intellectual property rights. So while many divers advise rejection of a computer that lacks RGBM, I’m of the completely opposite opinion.

The Shearwater Pursuit is based on the 16-compartment Buhlmann model used in many a computer and desktop decompression software package. My current Apeks Quantum computer, more of a recreational model, uses 12-compartment Buhlmann, which is likely good enough for recreational and entry-level technical diving. Buhlmann’s paper clearly describes the mathematical model and parameters for his ideas, and I’m sure, given enough time, that I could even design my own decompression software using public domain information. That gives me confidence that I clearly see the path from theory to practice.

Another attractive feature (in my opinion) of the Pursuit is the way conservatism is implemented. A lot of computers seem to have a non-specific conservatism setting like 10% or 25%. What does that mean exactly? My Quantum offers conservatism by faking the altitude setting, pretending that it is in one of three higher altitudes so that it calculates a more conservative outcome. I understand that it will do that, but what does that actually do to the dive? The Quantum will tell you how the NDL is affected but you can’t determine what your decompression schedule will look like.

The Pursuit on the other hand uses Gradient Factors, which change the parameters of the Buhlmann model in a well-defined way. Some desktop software also provide Buhlmann with Gradient Factors, so you can use them to generate dive tables which should correspond with the calculations made by the computer. So if the computer fails during the dive, switching to the tables at any point should be no problem, but if you come up early, or aren’t at maximum depth for the entire dive, the computer can give you credit and shorten your decompression time.

It accommodates 5 open-circuit gases, which is plenty for anything I can anticipate. Other than that, it doesn’t do very much, which may disappoint my inner geek but will do just fine for real-world diving. I’ve never seen one in the flesh, but reports from people who have and my impressions from pictures I’ve seen seem to indicate that it’s ready for rugged service.

As an aside, I was supposed to finish off my Assistant Instructor Course last night but the pool was unavailable. It now looks like mid-December. I may have to call PADI and ask them about Divemaster renewal since I don’t want to pay the renewal fee and the AI fee in the same month, when just one will do. I also have to visit the doc to get my medical sign-off, as a self-declaration is insufficient for the PADI pro ratings.

IANTD Advanced Nitrox Course November 26, 2008

Posted by Chris Sullivan in Dive Log, Training.
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At about the same time as I got my dry suit, I signed up for Advanced Nitrox, which covers the knowledge and skills necessary for accelerated staged decompression using enriched air (a.k.a. Nitrox). The certification is intended to employ mixtures of up to 50% Oxygen, which is not that much more than the PADI Enriched Air Diver Specialty, but the applications are quite different, as the IANTD course is designed for extended range diving into depths beyond the recreational limit of 130 feet and/or the no decompression limits.

The classroom sessions, covered many of the same topics of the Open Water and Enriched Air Courses, but in much more depth. Oxygen Toxicity especially is covered in much more detail, with greater attention to the CNS Clock, and the Pulmonary or “Whole Body” exposure calculations using Oxygen Tolerance Units and Unit Pulmonary Toxicity Dose. Having been interested in science my entire life, I ate this stuff up, and scored a perfect mark on all the tests. The final test I scored 19 out of 19 on a 20 point test because everyone in the class, including the instructors, agreed that there was no correct choice in the answers provided for one of the questions.

On the evening of July 13, 2006 I tried out a set of doubles for the first time at Big Bay Point in Lake Simcoe. I didn’t own my own set at the time and borrowed a set of 85 cubic foot steel tanks from Dave, a certified technical diver and assistant instructor who assists at the shop from time to time. I also used my Seaquest Raider BC, which although lacking a backplate is a reasonable but not ideal technical BC. It was also only my second dive in my dry suit, which made it all the more challenging.

The main point of the dive was to get familiar with the equipment. I had bought my Apeks ATX50 regulators (2 ATX50 first stages, with an ATX50 primary second stage and an Egress backup second stage), and had to sort out a problem right away with a leaking port plug, and then with the plastic tie on the regulator that was pressing against my lips, which Brad rotated slightly in place. We started out in about 4 feet of water and Brad signaled to me to swim around a bit. I went off about twenty or thirty feet into slightly deeper water as the dry suit, even with the doubles and 12 pounds of lead, wasn’t a comfortable swim so close to the surface. This was the one and only time that Brad has ever yelled at me, because he lost track of me and was concerned about my safety. Putting the whole thing down to a communication error, we continued with the dive down to a maximum of 48 feet, and an average of 21.

I didn’t have an SPG for my technical regulators, but the tanks had been filled to 3000 PSI and even with my high air consumption with the unfamiliar equipment we felt that at the relatively shallow depths that there would be plenty available.

After doing some switches between the primary and backup regulators, the next exercise was a “doff and don”, which with doubles in a dry suit and integrated weights is a real workout. Big Bay Point also has a thick silt bottom, so all the struggling you need to do creates a massive silt-out, which fortunately clears pretty quickly in the current. Once the scuba unit is off your back, it is very negatively buoyant, which is the opposite of an unweighted human in a dry suit. So you have to pull yourself down by the straps and wriggle back in, which is a lot of effort. I helped out this year’s class and they had exactly the same difficulty.

I can’t remember exactly what point in the dive it was, but at one stage I found myself breathing water because the plastic tie on my primary regulator broke (after being weakened at the beginning of the dive by rotating it) and it separated from the mouthpiece. I retrieved the regulator and took a few breaths from it, then switched over to the backup. All good – I passed my first equipment failure challenge. It would not be my last.

In the dry suit, I could not reach the tank valves. This is a mandatory skill in technical diving and the problem dogged me for quite some time until I figured it out, helped by some new equipment. I did the rest of my technical training in a wet suit, which was much, much easier in all respects. With a water temperature of 20C (68F) and a bottom time of 39 minutes, I could have just about used my 3mm wet suit (the only one I had other my 25 year-old suit that I swore never to use again), along with a hood. The hood makes a huge difference I’ve found, and is good for another 4-5C with any exposure suit configuration.

It was to be over a year before my next technical training dive. My class had pretty much broken up for various reasons, including lack of money for technical diving equipment. It turns out that a lot is required and you might as well budget $5,000 to get into it. The big ticket items are the BC, Tanks, and regulators, but accessories will run up the tab as well. Then of course unless you want to only dive with tables you’ll need two computers, or one computer and a bottom timer. The two computers are a nice way to go but good ones are really expensive. I like planning the dive with tables but using a computer on the dive, so I have an idea of what to do if the computer breaks, but can get the advantage of a multi-level dive in shortening the required decompression time.

Chest Compressions Recommended on Gasping Victims November 25, 2008

Posted by Chris Sullivan in Emergencies.
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I’m posting this because it’s a little different to the way I was taught CPR. We were told that if the patient is breathing, then the heart must be beating, and chest compressions shouldn’t be done. This article discusses patients who are gasping for air but otherwise unconscious. The Heart and Stroke Foundation recommends chest compressions with rescue breaths in these instances. According to another article in Science Daily, this is based on research from the University of Arizona, and a prior article citing several sources notes that there have been better outcomes with chest compressions only for  cardiac arrest, while rescue breaths are still helpful for respiratory arrest incidents like near drowning, drug overdose, or choking.

PADI Dry Suit Diver – Finishing it off November 25, 2008

Posted by Chris Sullivan in Training.
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3 weeks after the Scuba party at Innerkip, I had my brand new dry suit, of the trilaminate type and made by Northern Diver. I chose a model that zipped across the back, although a front zip model was also available, because I thought the fit would be more snug, and thus require less weight. This disadvantage, as mentioned before, is that it is less obvious if the suit isn’t zipped, and I did manage to jump in the water with it wide open. This was more embarrassing than anything else, and of course there were plenty of witnesses who remind me of it to this day.

I arrived at Big Bay Point at the usual time, and was surprised to see noone there from the shop, even though an open water class was going on. After waiting a while I called the shop and found out they’d gone to Johnson Beach, on the North Shore of Kempenfelt Bay and about 30 minutes drive. Finding my way there, it turned out to be a small beach at the bottom of a hill. Everyone was there including sunbathers. After dropping my gear off I drove up to the parking lot at the top of the hill and walked back down.

My first dry suit dive was pretty good. I hadn’t much on under it, as the water was a balmy 10C (50F). We swam out, did a fin pivot, then I was spun upside-down while my inflator button was held down. On the first attempt, I was almost at the surface before restoring my neutral buoyancy, although I was able to get right side up quickly and without difficulty. The next two attempts were much better. Another dry suit diver, Andrew Prestwich, with whom I’ve dived several times since, went through the same routine.

There was an advanced course going on as well, and Brad signalled Andrew and I to swim away so the student could search for us. Unfortunately we thought the “10” signal was 10 kicks, not 10 feet, and it was 20 minutes before we were found in the 10 foot visibility. That 40 minute dive concluded the formal part of the dry suit course, although we didn’t get to the second open water dive which is required by PADI for another month. That dive was also part of another course which I’ll save to a later post.

I had now finished my second specialty (the first was Enriched Air Nitrox), and was on my way to 3 more, qualifying me for the PADI Master Scuba Diver rating which I never bothered to apply for.

CPR Saves Diver’s Life November 24, 2008

Posted by Chris Sullivan in Emergencies.
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I’ve read a number of books on Scuba Diving Incidents – many divers are fascinated by them, if the search terms used to hit this blog are any indication. One thing I noticed is that every time CPR was considered necessary, the diver did not survive. So I was slightly surprised but also happy to read of an incident in Vancouver where an instructor was in cardiac arrest after surfacing quickly from 100 feet, received CPR, and lived. Having been trained to give CPR, I wouldm’t hesitate give it a try, but reading this gives me more hope of a positive outcome than I’d had before.

It would be great if this article helps motivate people to take the training if they haven’t already.

PADI Assistant Instructor Course – Day 3 November 24, 2008

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Day 3 started at 9AM with us back in the classroom. This time we covered pre-dive briefings for the open water class. These are quite simple. The skill is named, then the objective (i.e. perform a fin pivot by using the inflator orally; this needs to be read exactly from the cue card), then the value (if your power inflator doesn’t work, you can still achieve neutral buoyancy). Then you need to review the skills, especially with respect to the way they’re performed in the open water, and the hand signals.

The other parts of preparation are to determine how the skills demonstration will be organized, and anticipate the problems that might occur (my “students” used the power inflate instead of the oral inflate, and didn’t kick to start the ascent on the CESA – Controlled Emergency Swimming Ascent). After you’re done, you tell the students what they did right (positive feedback), provide them with reminders on the correct way to do anything you noticed that was wrong (without naming names), restate the objectives and reinforce the value. Another important point (to get a 5 out of 5) is  to use your assistant. I forgot to do this on the fin pivot, but got it right on the CESA, directing the assistant to keep an eye on the other students while I went to the surface with the student.

At 12:30 we were off to Big Bay Point in Lake Simcoe to simulate giving Open Water Training. There were 5 of us in the class. Steve Irwin (yes, that’s his real name) had me as his “student” for a mask removal and replacement. Meanwhile Brad had shown me a slate telling me to drop the mask while doing the exercise. Did I mention the water temperature was only 7C (44F)? I steeled myself for the shock of cold water on my face, and dutifully dropped the mask, making ineffectual arm movements to try and recover it. It put it back in my hand, with the thumb in the nose, and I successfully replaced it. Then to my surprise he asked me to do it again. He told me later that I really glared at him when he did that, but I did the exercise properly for him.

Ryan got me as his student for the half-way mask flood. Brad told me this time to bolt for the surface. I was wearing some new undergarments on my dry suit and was pretty buoyant, so I didn’t push it too hard, or he wouldn’t have been able to stop me. I also tried to warn him by being really hesitant and opening my eyes as wide as I could. He said later he saw me do that but didn’t realize the implication.

I’ll post the picture of all us, instructors, volunteer divemasters, and AI candidates when our surface support divemasters send them to me. We’re all standing in the snow in our dive gear, and we’re hoping that PADI will publish it in the Undersea Journal. I’ve dived in colder water but never in freezing temperatures outside (1C, 34F).  Three of the students were in wet suits, as was Brad. I’m happy not to have joined them.

So now all that’s left is the pool, and getting my medical signoff and I’m an official PADI Assistant Instructor. Too bad that in most students’ eyes AI ranks lower than Divemaster. My official last of the season record is now November 24th. I might try to squeeze one more in before the year is out, so I can have 50 dives in my log book for 2008. It’s a little less than I wanted, but without a trip to the Caribbean where I can chalk up a dozen dives, and the extra-long tech dives up in Brockville, I feel like I’ve done pretty well.