Freefalling Underwater

I highly recommend taking a deep diving course.

You descend the first few meters like you normally do, making sure you can equalize the pressure in your ears. Then… the brakes come off!

There is no speed limit on the descent, so you freefall faster and faster just like in skydiving. Instead of pulling a parachute, you inflate your Buoyancy Compensator Device (BCD) to achieve neutral buoyancy at your target depth. In this case, our target was 40 meters, and the bottom of the wall at Kontiki off Mactan Island, Cebu, Philippines, was conveniently almost exactly 40 meters.

This must be why I see so many photos of technical divers looking like skydivers. That does seem to be the natural position you take as you watch your depth on your dive computer.

If all goes well, you get narced up (nitrogen narcosis) on the descent. I don’t think I got narced up, but my instructor disagrees.

He made the point that I didn’t achieve neutral buoyancy at the bottom. I conceded that I was aware of that, but there were too many photos to take and too much debris to retrieve before reaching our No Decompression Limit (NDL). I think I would have the same buoyancy critique at any depth with that much going on in so little time.

Anyway, we’ll do another dive to 40 meters. I won’t need to take the camera, so that’ll be 1 less distraction. Plus, the camera shut itself off at depth anyway, and wouldn’t power back up until we were ascending.

I’m looking forward to my next jump! There is little sightseeing to do down there so far, but you can stop and smell the proverbial roses on the way back up.

Calculating Surface Air Consumption (SAC)

This slate may be a little hard to read, but the key numbers are 150 and 75, and 12 and 26. The 150 was my gauge reading at 12 minutes into the dive, when we reached 30 meters. The 75 was my gauge reading at 26 minutes, when we turned back.

So, my Surface Air Consumption calculation is (75 BAR used times the 11 liters in my cylinder) divided by the 14 minutes it took to breathe the 75 BAR, and divided by the absolute pressure of 4 at 30 meters, which equals roughly 15 liters per minute.

We could then use my SAC (15) to calculate our 40-meter dive:

1. Out of gas at 40 meters means (SAC x 2) for stressed breathing = 30, times 2 for air sharing = 60, times 2 minutes calming down = 120, times 5 absolute pressure = 600 liters of air needed.

2. (SAC x 2) for air sharing = 30, times the 4 minutes it takes to ascend from 40 meters to 5 meters at a rate of 9 meters per minute = 120, times the 3.25 average absolute pressure ((40 + 5) รท 2 = 22.5 meters) during the ascent = 390 liters needed.

3. (SAC x 2) for air sharing = 30, times 3 minutes for our safety stop = 90, times the 1.5 absolute pressure at 5 meters =135 liters needed.

4. 600 + 390 + 135 = 1,125 liters needed, divided by the 11 liters in our cylinders = 102.3 BAR required.

So, you’ll see that 120 is double-underlined. For safety, we decided to turn the dive at 40 meters at whichever came first, a 2-minute warning on our No Decompression Limit (NDL) or 120 BAR remaining in our cylinders.

In case you’re wondering, my instructor’s SAC is only 10, so multiplying my higher SAC of 15 for his air consumption was done for additional safety.

Deep Diving

My next specialty course will be deep diving. It will be my 5th diving specialty, and my 6th specialty overall.

The recreational diving depth limit is 18 meters. Anything below that, depending on who you are talking to, is a deep dive. My deepest dive to-date, however, has been to 30 meters. And I felt comfortable at that depth.

The deep diving course extends a diver’s maximum depth to 40 meters. My probable instructor has already spoken about bringing a relatively-low nitrox blend to maximize our bottom time.

Instead of being limited to 5 minutes at 40 meters, the right percentage of oxygen in our nitrox blend could give us up to 20 minutes at 40 meters.

I’m looking forward to it!

My completed specialties, in order:

1. Enriched Air Nitrox

2. Perfect Buoyancy

3. React Right (non-diving)

4. Science of Diving

5. Diver Stress & Rescue

Advanced Open Water Diver

Upon completion of my SSI Diver Stress & Rescue course, I was immediately qualified for Advanced Open Water Diver recognition.

The qualifications for SSI Advanced Open Water Diver recognition are 24 logged dives plus completion of 4 diving specialties.

This differs from the PADI equivalent, which only requires sampling specialties. SSI requires completed specialties.

My 4 diving specialties are, in the order I earned them:

1. Enriched Air Nitrox

2. Perfect Buoyancy

3. Science of Diving

4. Diver Stress & Rescue

I also completed the React Right specialty course, but it is not considered a diving specialty. It is a prequisite for the Diver Stress & Rescue course, however.

Next up: Master Diver recognition. The SSI requirements are 50 logged dives with 5 completed specialties, one of which has to be the Diver Stress & Rescue specialty. My 5th diving specialty will be the Deep Diver specialty.

17th Dive Against Debris

We retrieved 19 pieces of debris weighing a total of .5 kilograms from Shangri-la Marine Sanctuary off Mactan Island, Cebu, Philippines.

The overall group was quite large, so more was actually collected. I know that at least one diver properly disposed of her debris once ashore, but before I could ask her for her debris for reporting purposes.

My small sub-group collected quite a variety. We found plastic, wood, metal, and fabric. In fact, let me tell you a little something about the fabric….

I removed from the ocean floor a baby’s onesie and someone’s underwear.

How does a onesie or anyone’s underwear end up on the ocean floor? Who changed their baby or themselves on a boat, over a marine sanctuary, close to shore? We were less than 12 meters deep on a shelf, within the buoys marking the sanctuary’s snorkeling area!

These ocean cleanups, unfortunately, never cease to surprise me….

Diver Stress & Rescue!

After 3 diving days, I finally completed the SSI Diver Stress & Rescue course! This must be the most physically challenging diving specialty; I just can’t imagine any other course coming close.

The final dive is a culmination exercise. We started with a 20-minute fun dive, and it was truly fun. The highlight was this unending school of baby sardines that passed right over us.

Then, my instructor “lost” his dive buddy. We searched around our position for 1 minute. We couldn’t see her.

We surfaced, and my instructor was “too stressed” to look for our lost diver.

I can do it!

So, I took my dive buddy to search for our missing diver. She was not where she was supposed to be, so the search took quite a bit longer than it should probably normally take (for training, anyway). We did more of a real world search than a training search.

After we found her, I began the process of bringing her safely to the surface (she was unresponsive). For training safety, the lost diver is supposed to hold onto a cord in order to release air if our ascent is too quick. She wasn’t holding it, so I put her hand on it before I started our ascent. I wonder if I earned any bonus points for adding a real world safety precaution?

Anyway, the next challenge was pulling her to the beach while performing simulated rescue breaths every 5 seconds. Because she had been out of position, she was quite a bit farther away from shore than the training requires.

Nonetheless, I pulled her to shore in 12 minutes. That’s supposedly a good time. I heard of someone taking 20 minutes over the normal distance, and I took 12 minutes including the bonus distance.

I got her onto the beach and simulated CPR, at which point my instructor called the exercise. I passed.

But, I’ll tell you I was breathing heavy for quite a while. Swimming with an “unconscious” victim while performing rescue breaths, plus carrying the “victim” to shore, is a serious cardio workout.

I decided to quickly follow up this training with a fun dive on 35% nitrox (35% oxygen content, compared to the 21% oxygen content in the air we normally breathe). I thought of that as my recovery.

It turns out on that fun dive that I had to help a couple of divers with their positive buoyancy! I think this is now the 3rd dive that I’ve helped other divers, so maybe I’m suddenly more observant?

Anyway, my new challenge is to maintain these stress and rescue skills while hoping to never have to use them….

16th Dive Against Debris

We removed 4 pieces of debris weighing a total of .35 kilograms from Talima Marine Sanctuary, Olango Island, Lapu-Lapu City, Cebu, Philippines.

Fortunately, the dive site was relatively clean. Not only did we find little debris, we didn’t find anything disgusting. The latter seems to be happening more and more often.

Unfortunately, the Heineken bottle is disturbing. I have lived here for two-and-a-half years, and I have never seen a Filipino drink an imported beer. Filipinos like their cheap domestic beers.

Therefore, I suspect that it belonged to a foreigner. That seems more tragic to me, because most foreigners here are tourists, not residents. It is one thing to trash your own home, but I think everyone would agree that it is wrong to trash someone else’s home (even if they trash it themselves).

Non-Diving Specialties

Apparently, there is a difference between diving specialties and non-diving specialties.

I was very excited after completing my 24th dive, because I thought I qualified for SSI Advanced Open Water Diver recognition. The requirements are 24 logged dives and 4 specialties.

Or, so I thought.

It turns out that the React Right specialty is not a “diving specialty,” and therefore does not count as a specialty for recognition purposes. I did not know that. I have not seen that anywhere on the Internet.

React Right is a prerequisite for the Diver Stress & Rescue course, nothing more. Therefore, Stress & Rescue will count as my 4th specialty, following Enriched Air Nitrox (EANx), Perfect Buoyancy, and Science of Diving.

So, it’s not a big deal in the grand scheme of things, but since I have not seen this anywhere before, I’m sharing it in hopes of helping others manage their expectations. In my case, I simply celebrated one week prematurely.

Stress & Rescue (Buoyancy)

I am one dive away from completing my Stress & Rescue specialty. The other day, as my instructor and “victim” threw scenarios at me, something interesting happened: my dive buddy became positively buoyant during our 5-meter safety stop and almost surfaced.

I saw him ascending, raced over to him, grabbed his Buoyancy Compensator Device (BCD), and then dumped air from my BCD while fully exhaling. This created enough negative buoyancy, along with my dive buddy dumping air from his BCD, for both of us to become negatively buoyant enough to descend back down to 5 meters.

I immediately began thinking that this was the second dive day in a row that I had to do this. I also thought about how I used to struggle at my safety stops before I was properly weighted and understood how to control my buoyancy using my lungs.

So, even though the digital textbooks say that decompression sickness is the most common issue to worry about, I disagree. In my admittedly-limited experience, I would say that buoyancy issues are the biggest concern.

Yes, the problem with positive buoyancy is the risk of decompression illness. However, I have observed issues with negative buoyancy, as well. Negatively-buoyant divers who drift along a coral-covered wall do not necessarily notice that they are at 20 meters… then 25… then 30… then, in one case, 45 meters. This happened to a young, inexperienced diver who had not trained for diving to that depth. He also did not have a dive computer.

Plus, let’s not gloss over the damage divers can do to corals when they lack the skill to maintain neutral buoyancy.

Therefore, I rank buoyancy issues — positive, negative, and neutral (or lack thereof) — as the most common issues to be concerned about.

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