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July 29, 2006

I hate controlled emergency ascents

I hate controlled emergency ascents! Just wanted to get that out of my system.

A "controlled emergency swimming ascent," of course, is what you do when you're totally out of air and your buddy is too far away to help you out with his or her alternate air source. So what you do is look up, slowly release air into your regulator, going "ahhhh..." so that the remaining air in your lungs doesn't do damage as it expands while you get up to the surface. We practised that in the deep end of the pool two times today, sort of simulating things by not breathing in once the instructor gave the signal, then swimming horizontally and then up until we broke the surface. Then you flip on your back and blow up your BC by mouth as there is, of course, no air left in the tank. Or would not be if it were a real emergency.

Problem is, when there is no air, there is no air, and that is mighty spooky when you're underwater. We HAD air, of course, but even trying to play by the rules was hard. When you have to breathe, that's a pretty powerful urge, and it's surprisingly easy to freak a bit. I mean, how difficult can it be to hold your breath for a minute or so? Sometimes very. So the first time around I almost immediately feel I am out of air. I cheat a bit by taking two eensy little sips of air, but still gasp when I break the surface. And then blow up the BC from the tank. Wrong, wrong, wrong. We do it again and it goes a bit better. But I sure hope I'll never find myself in that situation. At the end of the class, Amanda goes: "One thousand pounds for me! Always." referring to the fact that once the pressure in your tank is down to 1,000 psi, you think about heading back up. So there.

The rest of Session Five of the PADI Open Water Scuba class was entirely more pleasant. We spent an hour or so in the classroom where instructor Chuck dispensed pearls of his very considerable wisdom, explained the pros and cons of different manufacturers' gear, and spent a good amount of time on the Dive Tables. Slowly and making sure everyone understood exactly how it all worked. No Decompression Limit. Residual Nitrogen Time. Actual Bottom Time. Total Bottom Time. Surface Intervals. Adjusted No Decompression Time. Again and again. Serious stuff that, even though computers do it all for you today. "But," the instructor points out, "you'd be surprised how many people never read the computer's manual!" Ten out of the 50 questions in the final test will be Dive Table exercises. And five of them will deal with the fine print on the table. Better hit the books one more time.

The rest of the three hours is spent in the pool. As I casually pick a BC, a regulator, and easily assemble the whole thing I marvel that just a week ago I had no clue how it all fit together. I remember how intimidating it'd all been and how we all had watched the instructor and then tried to imitate. Now it seems totally routine. Learning is an amazing thing.

We're switching buddies this time, so I team up with 14-year-old Spencer, a cool kid who's game for anything, and catches on fast. We check each other's gear, he and I, then do the giant stride entry. Now we're ready to acquire some new skills: removing the weight belt and putting it back on at the bottom of the 15-foor pool, two different ways. Then removing the BC and putting it back on, also at 15 feet. The belt can be tricky if you hold it too far away for your body as that'll throw you off balance, but Spencer and I do well. Same for the BC. That's a bit scary because you need to do it right or else you may yank the regulator's mouthpiece right out of your mouth. And it's kind of difficutl to find all the clasps and buckles without seeing them all. As with every skill, I wonder how different it will be to do it in open water instead of the calm, safe pool with instructor chuck and his assistant standing by.

Then we do three laps of just diving. That'll help us work on our buoyancy skills, something which I sometimes master, sometimes just can't quite get. I take the lead, with Spencer at my side. Amanda and Spencer's mom, both excellent swimmers, are much faster than I. But I am having fun. Later, the assistant tells me that I am not kicking my fins right yet. She said I was "bicycling." I wish I could see what I do wrong on video so I could correct. Later, I get proper instructions. Apparently, I did not have enough weight in my belt and so the assistant adds another four or five pounds into the pouch on one side of my BC. That helps, but now I am unbalanced, and then I lose the weight. Oh well.

Up on the surface we practice "tired diver tow." Two different kinds. No problem there. We don't even need masks, snorkels or regulators in the calm water of the indoor pool.

Since our last session two days ago, the center apparently replaced most BCs and most regulators with new and much better stuff, all Oceanic, the company that instructor Chuck swears by. The difference is indeed amazing. This time I pick a BC that's a bit too large. It works, but I definitely see the importance of getting stuff that fits. And I'd definitely recommend to anyone who is serious about scuba to get all their own gear right for the start of the course. Not just the mandatory mask, snorkel and fins, but also the BC, regulator and instruments. It just doesn't make sense to putz with beat-up equipment when you could spend the precious instruction time learning on your own gear.

Well, next week is the final test and some more water time, then it's on to the open water dives. Hey, the C-Card doesn't seem so far away now!

As I leave I wonder a bit about the dynamics behind a dive center operation. Where's the money coming from? Primarily classes? Or is it follow-up trips? Or perhaps sale of gear, which can easily run into several thousand dollars. I am a bit surprised about the instructor's very heavy bias towards one company and against another, and wonder what all is behind that.

Posted by conradb212 at 10:47 PM

July 26, 2006

Underwater again, and thoughts about the PADI approach

Yesterday was the fourth evening of my PADI Open Water Scuba course, and the second where I got to experience being underwater. The first time had been life-altering in a sense that is hard to describe. Humans simply aren't meant to breathe underwater, and the frist time you do so, it's had to shake the sense that this is all wrong. But that quickly changes as the air flows reliably. The odd sensation of breathing underwater is then quickly replaced by trying to keep up, getting used to your body moving very differently, by the laws of gravity no longer seeming to apply, and by essentially having to learn how to move all over again, like a baby.

Getting into Scuba diving really consists of two things. One is above water, the other beneath the surface. Above water you study books, listen to lectures, try to process and remember it all, and test your knowledge in quizzes and by answering the instructor's questions. In and under the water you try to remember it all, or at least a little bit of it, try to adapt to a new world where different rules apply, and slowly learn all the skills on how to act and move and get things done, all safely and, eventually, elegantly and effortlessly.

You can teach skills in many ways. PADI's approach has three prongs:

One is self-study via a rather voluminous perfectbound 260-page instruction book and a DVD that is an exact copy of the book, with (almost) all of its text spoken verbatum over video. The book has frequent multiple choice tests, all with the answers right there. It also outlines what you're supposed to take away from reading a chapter and encourages you to then underline the pertinent text. At the end of each chapter -- there are five -- is a "knowledge review," which you fill out (no answers printed here) and then hand in to your instructor. Don't underestimate the self-learning. It takes many hours to read the book and view the video, and while the tests in it are "open book," the ones you take during class are not.

The second prong are the classroom sections, and those appear to vary widely from instructor to instructor. From what I can tell, most instructors use classroom time to a) briefly go over the basics, and b), in much more detail, zero in on what they, based on their own experience, find truly important. PADI courses, which are meant to be accessible to everyone across a very wide age range, keep things simple and even complex concepts are described and explained in simple language. However, some concepts are not that simple, like understanding dive tables. While a lot of other stuff is common sense and self-explanatory, dive tables really address a very serious matter, that of how long you can stay at any given depth, and how the nitrogen that is still in your body after a dive affects the next one. Chuck, our instructor, spent much of his time on explaining dive tables and going through example after example. He went as far as saying that you may get this or that answer wrong in the final quiz, but getting dive table answers right is mandatory.

The third is pooltime and applying what we learned with actual scuba gear. This is the second time for us, so now we know how to pick a tank, a BC, a regulator, then assemble the whole thing. This time I find a BC my size, but pick a marginal regulator. While we finish prepping our gear, the instructor already explains the "giant stride entry" where the diver essentially walks off the side of the pool (or whatever). Hold onto your weight belt with your right hand and keep your mask firmly in place with your left. Jump, do this, do that, about ten steps. Hard to keep all those checklists in mind. Amazingly, it's no big deal. I jump in and quickly come up, mask still in place, and everything else as well. I give Amanda the "ok" sign.

While I am still checking this and that, making sure all is well, the instructor quickly goes through all we'll be doing in and underwater today. Then off we go, following him underwater. The rest is almost like a blur. Down we go, breathing underwater again. I now know why "ease of breathing" is listed as the most important thing when selecting a regulator. The one I have has a wimpy, chewed-up mouthpiece and every breath seems a struggle. It works, but I'd never pick this one. And its alternate seems identical in design and length to the primary. Though my BC fits much better, I still struggle with inflating and deflating it to achieve neutral buoyancy. I either float up or sink down. At the bottom of the pool we practice pivoting, i.e. keeping the tip of the fins at the bottom, then inflating and deflating just a bit so that our bodies move up and down. Then we do the same thing free-floating. I eventually get how to adjust buoyancy simply by adjusting my breathing, and feel a sense of elation when I do. We then go on just diving, following the instructor.

This gives me my first glimpse of the serenity, the just-floating, the peacefulness I am told to expect. I float through the water, occasionally check for my buddy, and force myself to view the pressure gauge. Clearing water that seeps into the mask is no longer an issue, I do it automatically. I never even paid much attention to equalizing pressure. That, too, seemed to happen almost automatically. Later the instructor's assistant tells me I am not using my fins correctly. I wish I could see that on video as I am very much determined to do it right. I do not want to look like the klutzy guy/gal they always show in videos as the example of how not to do it.

Then we move back to the shallow end to practice alternate air source ascents. That's what you do when your buddy runs out of air and you need to share yours. Or the other way around. So that's serious stuff. Again there are numerous steps. Do this, do that, make all those signals. I force myself to remember just the essentials: have the buddy to your right. Find your alternate with your right arm, give it to her with your right hand, then grab her right shoulder or BC with your right arm. Make sure she is okay with air, then motion up, inflate your BC, and go up. On the surface, make sure she is okay, then make her inflate her BC with her mouth. We practice that and it works fine, except really being a bit bewildered over all the many signs the instructors makes and wants for us to make. Then we go to the deep end and do it there. No problem.

Up we come and practice releasing, and then putting back on, the weight belt. And then taking off and putting back on the BC. One of my clasps will simply not release, so I am lagging behind, but eventually do it. I realize that making all this second nature is going to take some practice, given that we won't always do it within the confines of a small pool...

So that's the end of underwater session 2, or my second "confined water" dive. We get out, disassamble our gear, stow it away. I think I did okay, though certainly not with the effortless grace that I hope to achieve. As of now, I don't think my buddy views me as providing much help or guidance, which I sort of expect of myself given that I am so much older than her. I remember a stunning fact that the instructor had told us: the profile of the average Amercan scuba diver is male, age 52, overweight, half of them smoke, almost all drink. I fit the age bracket, the others do not apply to me, but I sure expected the demographics to be way different.

Later I find myself sitting in my own pool in the dark, just reflecting. I wonder what comes next, and where this adventure will take me. What wonders I will see, and how far I will go.

And later yet I discover another thing: a strongly chlorinated pool just about marinates you. Despite two showers I feel bleached! Of course, the fact that I'm spending the fourth day in a house without air-conditioning during the worst heatwave to hit my area in decades may have something to do with it as well.

Posted by conradb212 at 10:44 PM

July 20, 2006

The first breath underwater

What a day. I am not a scuba virgin anymore. Today, as part of my third session in the PADI Open Water scuba certification course, I breathed underwater for the very first time. This day will never happen again in my life and I feel like I am going to explode. I want to share, need to share, need to talk.

I left for the Hudson Dive Family Center in Rancho Cordova, Calif., with time to spare because I always like to prep a few minutes beforehand. I was the first one there and sat down to study my Dive Tables. Our little group of four finally assembled at 6pm or so, and the dive master, or was it master diver, told us the instructor was going to be a bit late as he was caught in traffic. She took us to the far end of the pool area and began showing us how to assemble the diving gear.

We got to pick a tank, then a buoyancy compensator vest (commonly called BC), then a regulator and finally a weight belt. I couldn't find a BC that fit quite right, and so ended up with one that was too small for me. That was when I realized that not having your own gear even for training and certification is a bad idea. Gear that does not fit fights you, and you don't want that while you learn and practice.

So there we were, like kids, all eyes on the dive master who showed us the basics. How to position the tank. How to first put the backside of the BC into the water so the strap that holds the tank loosens now rather than when you get into the water. Guide the BC's sling in the back over the standing tank, position the BC so the tank valve is 2-1/2 inches below the top of the BC, pull the strap tight, guide it through the loop on the buckle, then lock the buckle to secure the tank to the BC. An experienced diver never gives it a thought, but we practiced it three times to get it right.

Then how to put the regulator on, don't over-tighten, and yes, it can still rotate a bit. Make sure the second stage and the alternate air supply are on the right, the instrument and low pressure hose on the left. And the pressure hose goes into the BC with that snap-on valve. Grab the pressure gauge instrument, point the face away from you, and open the air valve on the tank to see if anything leaks, and also what the pressure is. One of the regulators seemed to lose air, but it turned out that the company who makes it is big in the Midwest where diving in cold quarries is popular, and so they added a tiny little valve that constantly blows a bit of air to prevent freezing.

Now the instructor shows up and quickly takes over. The Aquatic Center was very hot and humid and I was sweating up a storm while everyone else seemed comfy (maybe growing up in often icy Switzerland never quite lets me get used to the heat here in Sacramento, California), and in time all the various parts begin making sense. Even all the snaps and clasps and Velcro on the BC. We didn't get to wear wetsuits, so my weight belt had all of 8 or 10 pounds in it.

Then it's time to pick up all the gear and head on over the shallow end. Man, the stuff is heavy! Instructor Chuck, a former Navy Seal with supposedly 11,000 dives under his belt, now explains how to don the gear, how to place the BC just right, and he shows two different ways to put it on in the water. Easy for him to say. He just flips and glides right into it. My undersized BC is more recalcitrant, but eventually it goes on. I mentally note that there's another good reason for a wetsuit: all that gear doesn't scratch up your skin if you wear a suit.

So now we're in the water and go through some procedures. Sweep your arm back to get the regulator and the backup air supply. If you still can't grab it, reach to the first stage on top of the tank, then follow the hoses. And this is how you operate the BC inflator. And so on. Oh, and wear the mask under your chin, not on top of your head, else you'll eventually lose it.

Then without further ado the instructor makes us go under and breathe underwater for the first time. I had expected him to wax poetic a bit on what a life-altering experience that was going to be, forever changing everything, as the PADI book so nicely does, but perhaps ex-Navy Seals aren't poetic. Or maybe it's just Chuck who isn't. He is very poetic about lobsters, though.

So underwater we go and I ... breathe. A moment's hesitation, but no problem at all. Hey, cool. Big air bubbles bust out in front of my face and rapidly rise to the surface. Breathing is loud. This is the first time I realize that whatever I expected to be an issue wasn't, and whatever I expected not to be was.

I thought the BC would make positioning in the water easy, but I was forever compensating. I had fully expected a pinched nerve in my upper thigh to become a problem as it's been giving me sharp pains for the past few days. It never did. I thought my toes would cramp from the still unusual shape and pressure of the diving booties and my big Scubapro Twinjet fins. The ties did not cramp, but my legs later sure did. Chuck now assigns buddies. Mom and son get together, and I am buddies with Amanda who, as she repeatedly pointed out, has a timeshare in Bonaire.

Chuck now briefly reminds us how to clear a flooded mask and we are to do that two or three times, or until we are comfortable. So we deflate the BC, sink to the bottom (of the shallow end) and practice. I can do it, but it isn't my favorite part as I do not like water in my eyes, especially when it is chlorinated. But it works much better than I thought it might. Then Chuck instructs us on how to take the second stage out of one's mouth and put it back in. No problem there. Then he very quickly recaps the hand signals, and now it's time to go deep. Or as deep as the pool goes, which is about 15 feet.

Off goes instructor Chuck, and us buddy pairs are to follow, with the dive master bringing up the rear. I am having a hard time descending and try to use the air control mechanism on my BC to compensate. Chuck comes over to help me. I'd had two problems: the ill-fitting BC's inflator and deflator buttons were almost out of my reach, and apparently I was pushing both, or the wrong one. Finally I reach more or less neutral buoyancy, we reach the end of the shallow end of the pool and begin the descent.

Here I was fully prepared to encounter significant problems with equalizing my ears. But none happened. I pinch my nose closed through my mask and blow against it to adjust pressure in my ears. My right ear did a little hiss when it equalized, the left one a bit later. There never was any pain. On the other hand, I struggle more with the big Twinjet fins than I expected. The dive boots feel great, but I have definitely not mastered how to use the powerful fins. I remember an instructor's graceful movements I've seen on a training video and try to move my legs like that. I probably failed miserably, or maybe not.

In the meantime, I am getting ahead of my buddy (budette?). I look back repeatedly, but find it not so easy to stay close to her. Other times we bump into each other. I find myself reluctant to touch her, grab her, or guide her in our efforts to move underwater. It just doesn't seem proper. But we valiantly practice our signs. "Are you okay?" "I am okay." Then we sit at the bottom and Chuck makes us flood and clear the mask again. Then we do a controlled ascent. My buddy and I do a very slow one. It's a nice feeling to slowly float up. Then down again, and now we're swimming after Chuck, diving around the pool.

Here I notice a few other things I did not expect. Breathing is not hard, and I think I do it right: slow, deep breaths. But at times I feel I am cramping my mouth on the mouthpiece. One time, while clearing the mask I inhale a bit of water and choke for a second, then, remembering what I'd read, cough into the second stage mouthpiece. No problem, but I become quite aware that should I panic, which I was never close to, that would not be a good thing. Equalizing continues to be a non-issue.

By far the biggest thing I notice is that I feel very disoriented and really never quite know where I am. Looking for my buddy is harder than I thought it'd be, and there is much more tunnel vision than I expected. I never felt I truly knew where I was. So then my buddy floats up and has trouble adjusting her buoyancy. Chuck goes after her and she comes back down. I note again how much easier the breathing is than I expected, but how much harder orientation and movement control. Eventually we end up back in the shallow end. I realize that I had not checked my instruments once. And that I am probably not going to like a console that’s freely floating around. I plan on using wrist-mounted gauges instead.

So now we stand in the shallow end and check our air. We'd started at 3,000 psi. Three of us were down to 1,800 psi, one at 2,000, and the dive master at 2,500. I don't know how long we'd been down, but the air sure seemed to go a lot faster than I expected. Chuck now explains the remote possibility of a second stage becoming stuck open, with all the air escaping rapidly through the mouthpiece. If that happens underwater, the trick will be to gulp some air until a solution can be found. We practice breathing from an unbroken stream of air by depressing the purge valve. My buddy first has the mouthpiece in her mouth all the way, closing off the flow of air. I show her how to practice and we both find it easy. It goes through a lot of air in a hurry.

Now it’s time to experience what it feels like running out of air, and how to signal for help. Chuck takes us down underwater and, one by one, turns off our air, making us watch the pressure gauge as it drops to zero. We give the "out of air!" signal and he reopens the air valve. No problem.

Up we go and now we have to show that we can snorkel. I like snorkeling and have no problem doing it with the dive gear on. At the deep end of the pool, the instructor makes us deflate our BCs completely and stay afloat using just the fins. What a difference! With the weightbelt and no wetsuit I am definitely VERY negatively buoyant, and powering the big fins almost immediately cramps my calf muscles. I try staying afloat as best as I can but then inflate the BC so I won't go under, yet still find myself grabbing for the side of the pool. "Not in my ocean!" Chuck growls at me.

So that's that. Chuck shows us several elegant methods on how to get out of the BC and heave it up the side of the pool. Then we carry everything over to the water tank so we can rinse things out. Rather casually, actually. I was prepared for a much more thorough cleaning, as described in the course book. Then we carry the tanks back, with the plastic dust valve off. The dive master says that's so they know they are empty and need to be filled. No classroom for us tonight. It was all pool.
I talk with instructor Chuck for a few minutes and ask him what he considers the difference between the various scuba certification agencies. He explains who all they are, how large they are, and what their priorities are. He says he's certified at many levels both with PADI and with NAUI. He describes PADI as recreation and pleasure oriented and NAUI as more technical and demanding.

So then I get dressed, and leave. I see Amanda on the way out and she goes, "Bye buddy." Though it’s night, it is still 103 degrees outside. I sink into the seat of my PT Cruiser, start the motor and turn the A/C to max. I feel thrilled, excited, exhausted. I know that I had just done something that I will only experience once in my life. My first breath underwater. I want to shout, scream, and feel a huge need to discuss this all with someone close to me.

An hour later my emotions are still in overdrive. I am not a scuba virgin anymore, and somehow writing words onto a computer screen doesn't fill the void and desire to talk and discuss. The good thing, of course, is that having no one to talk to forces me to write it all down. Hey, I am a writer. And so now anyone who's never done it knows how it feels the first time, or at least how it felt to me.

Posted by conradb212 at 10:06 PM