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Flying After Scuba Diving September 30, 2008

Posted by Chris Sullivan in Dive Log.
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Every open water student learns that you need to wait before flying after you dive, and there are published guidelines to minimize the risk of decompression sickness

This post, however, continues my diving life story down a very long tangent with my decision to also learn to fly airplanes. While these two activities are incompatible when done too close together, I think a lot of divers are interested in flying and vice-versa.

My first flying lesson was September 1st, 1983, the day that KAL 007 was shot down by the Soviet Union, and not long after I’d done the last of my abandoned advanced open water course. I was taught mostly by John Briglia from the London Flying Club. I’m not sure that the club still exists, as Google doesn’t turn up very much, but I moved away from London in 1990 so I’ve lost touch. I found out later than John used to hang out with an old friend, Danny Blasco, when they used to blast around London on Honda 750-4 motorcycles. When I mentioned this to John he told me he was trying to live down those days.

What I remember mostly about the lesson was the yaw when I applied power on take-off and the impression that it handled more like a boat than a car. For my next lesson almost 3 months later I had a bad hangover, which is something to be avoided. I had simply forgot that I had a flying lesson in the morning until I got home late that night. Anyway, I think it was OK – at least the instructor didn’t give me a hard time and we didn’t crash. I had my first solo on May 27, 1984 and passed my flight test on October 29th, with about 50 hours of total time.

I love flying. I went on to get a commercial license, and night, multi-engine and instrument ratings. Unfortunately, the cost of flying strongly outpaced inflation, and keeping up the skills requires a lot of time and money, so my last flight was to Pelee Island in June of 1995. As a point of comparison, if I want to go diving I go to the dive shop, fill up my tanks, and dive. Other than gas for my car the cost is zero, unless I want to boat dive, get enriched air (although sometimes I get that free) or stay in a motel. To fly for an hour, even in a little Cessna 152, I still need gas for the car, but will spend $150 or more.

You won’t find the history of learning to fly in this blog – it’s about diving, after all. Very occasionally, the two passions would meet, and I’ll mention that.

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Exercise after Scuba Diving September 29, 2008

Posted by Chris Sullivan in Fitness and Nutrition, Training.
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After Saturday’s long day of shallow diving, I rightfully felt pretty tired. Getting home later than usual, I wasn’t all that keen on doing my usual Saturday run, and as my wife believes that it is my duty after going diving to do some chores around the house (more about wives and diving in a later post), I reluctantly chose to forego the exercise for the day.

My Sunday run is the longest of the week, but within a minute of starting I knew it was going to be tough. Even though the run is also the slowest of the week, my heart rate climbed rapidly right out of the gate. So I had planned to run for 85 minutes but only managed 70. For the last 6 or 7 minutes my heart rate was 95% plus of maximum. Mind you, my maximum heart rate is only 171 (167 by the 220-age formula), down considerably due to age. For the last 15 minutes I kept my heart rate at about 80% by adjusting the elevation on the treadmill and walking, so I’d at least exercise for the planned amount of time.

This extra fatigue could have been due to the nature of Saturday’s diving, tiredness from the exertion (i.e. not due to compressed air), fairly recent changes in diet, or maybe even the fact that I missed Saturdays’s run. I have completed the long run without difficult on other occasions even after diving the same day, so it may take some time to figure out what’s going on.

Guidelines for exercise and Scuba are usually in regard to the risk of Decompression Sickness (DCS), and usually go something like this:

  1. Exercise before diving is OK, but heavy exertion immediately before diving is probably inadvisable.
  2. Excess exertion at depth is to be avoided, as increased circulation will increase the perfusion of compressed inert gases, like Nitrogen or for deep diving, Helium, into the tissues of the body. It can also increase Carbon Dioxide levels in the bloodstream, which cause or aggravate Narcosis and CNS Oxygen Toxicity.
  3. Light exertion on decompression stops is probably a good thing, as increased circulation will help flush those same compressed inert gases out of the body.
  4. Heavy exertion on decompression stops or immediately after diving is potentially a bad thing as inert gas bubbles can pass from the venous to the arterial side of the lungs’ alveoli leading to Neurological DCS.

One 2006 study suggests that heavy post-dive exercise might be beneficial, although it was done on fit military divers and cautions that more study is required for average sport divers. Other articles more or less support what I’ve outlined above.

General fitness, which is why I’m running in the first place, is universally agreed to be a good thing. Aside from specific benefits in the prevention of DCS that are often mentioned, being fit means I’m less likely to be out of breath either underwater or on the surface, and able to respond to the demands that may be placed on me to handle difficult situations or emergencies.

Yesterday’s Open Water Diver Class September 28, 2008

Posted by Chris Sullivan in Training.
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While the dive club goes off to Bala for some weekend fun and diving in Lake Muskoka to do cool dives like the Waome, I’m hanging around town. Because so many of the assistant instructors and divemasters are going, the shop (not to mention the instructor) was pretty desperate for some help with the Open Water class up at Big Bay Point, so I offered to help out on day 1 with Open Water dives 1 and 2.

Open Water Class Day 1 Sep 27 2008

Open Water Students with Instructor on Big Bay Point Dock

Eight students turned up instead of the five we were expecting, and apparently the divemaster candidate who was also supposed to help went off to Bala himself. So instructor Dave Dowling and I were left to contend with the students, several of whom were quite young (12, 13 and 15). Being concerned for their well-being, we decided to split the class into two groups of four. So we had four dives instead of two, not counting my 5 minute solo dive to set the flags.

For the most part, the students were just fine. Dave handled one panicky student during the mask flood exercise but kept her out of trouble and brought her straight up. I was on the surface with two of the four students when this happened, so I dropped down to retrieve the fourth student who was told to wait while he dealt with the problem. I found her searching under a log for crayfish, right where we left her 60 seconds earlier.

All in all it was a long day, and a bit hard on the ears with 7 separate descents to 30 feet or so, but I felt we did a good job teaching and keeping the students safe. While we had good visibility of about 20 feet, there was a strong current from the East on the surface but not at depth, so the most difficult part of the day was to keep the students from drifting away.

Oh yes, it was fun despite all the work. That, and learning to be a better diver, is why I do it.

First trip to Tobermory and Fathom Five National Park September 27, 2008

Posted by Chris Sullivan in Dive Log.
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My last dive trip of 1983 was from September 16th to 18th to Tobermory, Ontario, which is home to Canada’s only underwater national park, Fathom Five, home of numerous shipwrecks. To give this an historical context, it was 10 days after the Soviet Union shot down Korean Airlines flight 007, and the first day of diving on the Saturday was the day Vanessa Williams became the first African-American to be crowned Miss America. The following weekend, a Soviet military officer named Stanislav Petrov narrowly averted accidental full-scale nuclear war by correctly interpreting a warning of incoming American missiles as a computer error. Ah, those were the days!

I’ve been to Fathom Five National Park six times now, most recently last August, and it is one of the two best spots in Ontario for diving. The other is the St. Lawrence River between Kingston and Brockville.

So it was a Friday in mid-September, when the water is still quite warm (relatively speaking), that we drove up from London to Tobermory, camping overnight in Cyprus Lake Provincial Park, now part of Bruce Peninsula National Park.

The first dive was in Big Tub Harbour on the Sweepstakes. This wreck is an excellent beginner wreck although today access is more restricted than what it was in the eighties. At a maximum depth of 15 feet, the wreck can actually be seen from space! If you followed the link to Google Maps you can see the outline of the ship just to the right of the discoloured water with the bow pointing to about 5 o’clock. The ship lies on a sandy bottom with some silt, rocks, debris and a few weeds. Even with a starting PSI of 2150, my buddy Howard Van Stone and I stayed under 40 minutes and still came up with half our air.

Later that day we went to Flowerpot Island for a “cliff dive”. The island has unique rock formations and the underwater landscape there and in much of the rest of the area is quite interesting. Personally though I prefer shipwrecks but at least Howard and I set a new personal depth record of 55 feet.

On Sunday we dove the James C. King Shipwreck near Russell Island, which is also reputed to be the location of the wreck of Robert de LaSalle’s Ship, Le Griffon. The King was my early favourite for wreck dives. At Fathom Five, even in the eighties, you had to purchase a permit to visit the park. The pamphlet they gave you mentioned a spot at a depth of 60 feet where you can swim under the hull. I think the spot still exists but it’s no longer mentioned. I imagine they think it’s too dangerous now as it’s just big enough for a diver to get through. This dive maxed out a 90 feet, with a bottom time of 20 minutes.

The final dive was at the Grotto, also known as the Caves. The Grotto is a nice little dive, maximum depth is about 30 feet although nearby it drops into much greater depths. Two separate short tunnels, the more northerly one being much wider than the other, provide access to the grotto, which can also be accessed by swimmers from the shore. Caution is required to avoid one from landing on you. Howard and I were out of the water a bit before 4pm and we headed back to London.

Later today I’m off to Big Bay Point to help with an open water class.

UWATEC FS-1 Compass September 26, 2008

Posted by Chris Sullivan in Equipment.
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My New UWATEC FS-1 Compass

My New UWATEC FS-1 Compass

I just bought a new UWATEC FS-1 Compass to replace the ScubaPro Compass I bought in 1983 to do my NASDS advanced course. The ScubaPro is lying at the bottom of Lake Simcoe after it slipped off the wrist band. I usually say I just threw it away as the card had locked in position and thus no longer pointed North, which made navigation much more difficult.

The new one is much nicer, anyway, and I will try it out tomorrow, again in Lake Simcoe, even though I also have a compass in my console. Why do I need two? Well my technical rig doesn’t have a console, so I need a separate wrist-mounted compass so I can find my way around on technical dives. In fact, there’s very little of my rec gear that I can actually use for technical diving. My 2 AL80s are kitted up to sling on my BC, but I’m planning to get a separate steel deco bottle of lower capacity for better balance. The AL80s will still be useful for staging extra gas for wreck diving, but they’re too big for comfort to carry around just for deco.

Anyway, it’s a nice looking compass, and reads from both the top and side. It will work with a tilt of up to 15 degrees, which should be plenty. One thing that puzzled me was that the instructions listed separate part numbers for the Northern and Southern Hemispheres. I had had to turn to the trusty Internet for an explanation. It’s something to bear in mind if you’re travelling south to go diving. I’m diving my new compass when I assist with an Open Water class at Lake Simcoe tomorrow.

Tourist Dies on a Discover Scuba Diving Course September 26, 2008

Posted by Chris Sullivan in Emergencies, Training.
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Reported Tuesday on the Cyber Diver News Network (CDNN), and Wednesday in an article in Pacific Magazine, a 48 year-old Japanese tourist died during a PADI Discover Scuba Diving resort course in New Caledonia. Having not much to go on from the article, except that the Nouméa Diving Manager suggested that the diver died because he panicked, and that he was treated for severe brain damage before being pronounced dead, I can’t really comment on the incident.

However, I have heard horror stories from several people about so-called resort courses. My dental hygienist’s told me a story of a close friend who suffered Pneumothorax, while a friend told me he was put in charge while the instructor/divemaster sorted out a problem with one of the other divers. I tell my friends not take resort courses, but rather opt for the full open water course. It’s not a big investment in time when you consider your life or health is at stake. Mind you, a well-run resort course should be quite safe, but how can a neophyte tell the good from the not-so-good?

Having said that, my dive shop (not mine, but the one I hang out with) runs Discover Scuba Diving in the local pool. Not quite as exciting as a tropical reef, it gives the students the experience of breathing underwater. We also give them instruction in the shallow end and only let them into the deep end with one on one supervision, so we can stop them or slow them down if they panic and bolt for the surface. I don’t think you can safely take someone to depth without constant supervision until they’ve gained familiarity with the equipment and basic procedures. Our open water students are sometimes prone to panic, even after the pool training, and we always have divemasters hovering behind them to stop them from bolting.

On the training panel at the 2008 DAN Technical Diving Conference, Tom Mount’s opinion was that 15 percent of all students can go through training just fine but will always panic under stress in a non-training setting. Another 15 percent are prone to panic but in a given situation may or may not do so. I’ve experienced the occasional bout of anxiety under water, but once recognized, have been able to think through the possible responses and choose an appropriate one first. Following the rule “stop, think, then act” has always kept things from spiraling out of control.

It was interesting that the article mentioned PADI by name, and another article slams the PADI Scuba Diver Course, which is an abbreviated version of the Open Water Diver course where the certification carries additional restrictions. Other agencies offer similar courses to Discover Scuba Diver and PADI Scuba Diver (the latter not mentioned on their web site) but I do agree with the training panel at the DAN Technical Diving Conference who were deeply concerned about the dramatically lower requirements for certification compared to 30 or 40 years ago, and how these may backfire on the industry. If a new diver has a bad experience on their first few dives due to inadequate training, they are unlikely to try diving again, and probably tell their friends what a horrible experience they had. And while the training may be sufficient to dive within the restrictions, they will not necessarily be followed as the article points out.

Many people I speak to think diving is dangerous, and stories like the ones reported here contribute to those opinions. The home page of CDNN would certainly make you think that diving accidents are rampant.

Advanced Open Water Training September 25, 2008

Posted by Chris Sullivan in Dive Log, Training.
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The year following my open water certification, 1983, I signed up for a NASDS Advanced Diver course. I never finished it. It’s a little hard to tell from the timelines in my log book but my best recollection is that we didn’t complete our drift dive by the time the season came to an end, and didn’t manage to regroup the following year.

So on May 15th, 1983 I found myself back at Innerkip to start my advanced course on a cloudy day with light showers. The first dive, with a stated purpose of refamiliarization, also involved underwater search during which my buddy Steve Parker and I found both submerged cars.

On June 5th the advanced course really got going when buddy Scott McArthur and I, along with a couple of other buddy teams, attached 1800 pounds of lift bags to one of the cars (a Bobcat) and raised it off the bottom. When I compare that to my PADI Search and Recovery course where I used a BC to lift a 12 lb weight belt off a sandy bottom in Jamaica I question why SSI wouldn’t swap their own advanced card for a NASDS one. Maybe our instructor, Mike Flanagan, went a bit overboard compared to the course requirements.

June 7th was the night dive with buddy Steve Parker. We had glow sticks attached to each tank valve, and a note in my log says that my rented dive light ran out of charge. Our 40 minutes bottom time use 1400 PSI with a maximum depth of 20 feet. The following weekend we did a search and recovery dive (for a missing lift back) and two navigation dives.

Slightly over a month later we were in Sarnia, Ontario on a hot (34C), diving a couple of wrecks under the Blue Water Bridge. One wreck, the “Monarch”, lies in the middle of the St. Clair River at a depth of 60 feet. My log book notes a “moderate” 6 knot current. I have memories of hanging on for dear life, especially when the freighters went overhead. The other wreck was known only as the “Barge”. Due to the low visibility (5 feet), on the way back up the line from the wreck, I had a compelling illusion that the line was pulling me through the water, rather than being in a heavy current holding on to a fixed line.

A week later on August 21st, we were back at Innerkip for a mapping and a navigation dive. That was the end of the advanced training. I think most of the class also had this problem, but 25 years on I think back and think that I was let down by the dive shop.

These days you can do an advanced course in a weekend, or a couple of days at a resort. Thinking back to the 11 dives we did that didn’t even get us to the end, and the heavy duty nature of some of the dives, there’s no comparison between the eighties training and what we have today. It was miles harder back then.

The Pesky Zebra Mussel September 24, 2008

Posted by Chris Sullivan in Ecology.
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I noticed a recent article on the Chicago Tribune web site about an effort to clear Zebra Mussels from a local quarry. It was known at the outset that it would be a fruitless effort. There is no known way to clear an infestation. Even in Europe, where they are a food source to predators, the infestation is virtually unchecked.

One thing I didn’t know was that divers themselves are sometimes responsible for the spread of these pests, as their larvae will stick to diving equipment, especially wetsuits, even when they have apparently been dried. The recommendation is to wash them and dry them as much as possible if moving from an infested to an uninfested lake, making sure that no damp spots remain on any part of the equipment (almost impossible with my booties, which have no zipper).

While Zebra Mussels are certainly a nuisance as they cover everything in sight, they have improved visibility in the lower Great Lakes and the St. Lawrence River by leaps and bounds. Without them, there would be very limited diving in the St. Lawrence due to poor (less than 5 foot) visibility.

The article also has a picture of a diver feeding Zebra mussel pieces to the local fish population. One way of passing the time on deco stops in the St. Lawrence is to carefully crush the Zebra Mussels between your fingers and feed them to the Gobies. Another Great Lakes invader, the Goby is everywhere, and you can gather quite a crowd of them in no time with a few well placed Zebras. It’s a lot more fun than playing rock-paper-scissors with your dive buddy, and while killing Zebras may appear cruel, they’re not supposed to be there in the first place.

Glove with Zebra Mussel Damage

Glove with Zebra Mussel Damage

Another downside of Zebra Mussels is that their shells are sharp and they cut your gloves, and then your hands. Technical Diving in the St. Lawrence River often involves clinging to rocks in a heavy current. And when those rocks are encrusted with Zebra Mussels, that can hurt a lot.

Diving Fitness: A Kindred Spirit September 24, 2008

Posted by Chris Sullivan in Fitness and Nutrition.
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Last Sunday the Allentown Morning Call named 49-year old Joanne Rooney from the small town of Bath as their “Workout Winner”. Joanna’s favourite exercises are scuba, running and lifting weights. She sometimes swims or uses an elliptical training instead of running to build her endurance.

Like me, she works out early in the morning to make sure she has time. She names Stan Waterman, now 86 and still diving, as her role model.

Oxygen Toxicity and Underwater Convulsions September 23, 2008

Posted by Chris Sullivan in Emergencies.
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In the DAN Technical Diving Conference session on CNS Oxygen Toxicity, Dr. Simon Mitchell and Dr. Bill Hamilton mention the appropriate method for handling convulsions under water. An underwater convulsion is a very dangerous thing, as the regulator will usually come out of the diver’s mouth as they convulse. Replacing the regulator is usually impractical, although if the convulsion is recognized by another diver at the onset it is possible that it can be held in place until the convulsions cease.

I have taken three courses on using enriched air (a.k.a. Nitrox) in diving. Enriched air has a higher percentage of Oxygen than atmospheric air and is usually implicated in Oxygen Toxicity, although it is also possible with air alone if the depths are great enough. These state the following:

  1. DSAT Tec Deep: “The general recommendation is to wait for the convulsion to cease and then bring the victim up, maintain a neutral head position that allows air to escape from the airway”
  2. IANTD Advanced Nitrox: “DO NOT: Raise the victim until the convulsion has ceased; There is a risk of embolism!”, etc.
  3. PADI Enriched Air Diver Specialty: “If the diver has the mouthpiece in place, hold it there; but don’t waste time trying to replace it if it’s not. Immediately bring the diver to the surface and check for breathing….”

Dr. Hamilton recommends bringing the diver to the surface immediately. His rationale is that while there is a small chance of an embolism, there is a certainty of drowning when the diver has no airway. Dr. Mitchell added that it is a misconception that the diver’s airway will spasm shut during a convulsion, which would prevent expanding air from escaping through the diver’s mouth or nose and thus precipitate an rupture of the lung tissue. According to Dr. Mitchell, this has been shown time and again not to be the case. So the latest information appears to side with the PADI.