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Scuba diving

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Ok, I'm going to show my age, but some 53 years ago I was NAUI certified and there was very little technology available. We used double hose regulators and no air guage, these tanks had a J-valve that you pulled down on when your air was getting low. Anyway, as with anything else you will feel more comfortable the more you dive. Relax, as was said above take your time and error on the conservative side. Look at your equipment and try to relax and enjoy the area you are diving in, as had been said the DM will be in control. Although when we were diving in Fiji the DM got lost and we had to surface because are air was low, we were not with a group just my wife and I. Enjoy.
 
Sorry to be the party pooper... but Spare Air and other bailout solutions are (in my not so humble opinion) totally bogus, ESPECIALLY for a beginner.
Watch your SPG. Actually, since you'll tell your dive guide that you are new, he will remind you / ask you for your pressure. And end the dive when it's time to go up.
A dive should never run out of air.
Agreed. But every year divers die because they run out of air. Did they screw up and make fundamental mistakes? Obviously. And they died.
Should beginning divers learn to monitor their SPG? Obviously. And sometimes they die because they fail to do so. Even experienced divers can make stupid mistakes.
Having a truly redundant air supply can save your life, whether it's a SpareAir or a pony bottle. The cost is modest.
I've never used my SpareAir in hundreds of dives. Hopefully I never will.
Dirk, if you don't want to use one, I'm fine with that, it's your choice. But I think you are doing beginning divers a disservice by telling them a redundant air supply is a bad idea.
 
Agreed. But every year divers die because they run out of air. Did they screw up and make fundamental mistakes? Obviously. And they died.
Should beginning divers learn to monitor their SPG? Obviously. And sometimes they die because they fail to do so. Even experienced divers can make stupid mistakes.
Having a truly redundant air supply can save your life, whether it's a SpareAir or a pony bottle. The cost is modest.
I've never used my SpareAir in hundreds of dives. Hopefully I never will.
Dirk, if you don't want to use one, I'm fine with that, it's your choice. But I think you are doing beginning divers a disservice by telling them a redundant air supply is a bad idea.
Well, I'm not sure how much you dive with beginners and I'm not sure how much time you spend keeping them save. I think I mentioned somewhere up thread that I'm a dive master and tech dive master... I have a four hundred dives in the last five years and have seen my share of divers who got confused by their gear and who got into trouble because they were told by experienced divers about all the different things they needed to carry on a dive to be safe. Specifically I have seen a diver who got separated from the group because he was absorbed in trying to fiddle with his Spare Air. And another diver who for some reason a few minutes into the dive switched to his spare air, then was out of air a few minutes later and did an emergency ascent from 60ft/18m in complete panic, costing the rest of us the dive.

I have not seen a diver on rented gear run out of air without the dive guide putting them on their octopus long before said diver's tank was empty.

So based on my experience, if you are diving in a recreational environment, warm water, good viz, with a guided group (and not with one buddy of unknown skill in a murky quarry) then the risk / reward profile of a Spare Air or other pony bottle setup is significantly bigger than 1.
 
I went as far as getting my AI under PADI, so have seen hundreds of different newb students. (And been through the whole PADI salesmanship course for selling gear ;) )

The one thing you can guarantee is most are already suffering from a level of task overload as it is, (many even at the surface never mind at 18m). Very, very few straight out of OW cert are completely comfortable with the gear they learnt in, and adding anything more is counter productive IMO. Effectively they are ready for guided dives with a DM, using the basic kit they learnt in, nothing more.

As DirkH says many times you will see one of the group end up on the DM's octopus, been there done that got the T Shirt from both sides! (Now sometimes I've seen it used as a way of extending the dive to hit a reference point, but that's a different argument. )

Runaway buoyancy is probably the biggest concern from a dive ops POV on these sort of dives (especially with boat traffic / jet skis / etc), not gas management. Fiddling with stuff often precedes such events.
So no answer is right or wrong, but we need to look objectively at the risks and appropriate kit for the given situation and dive plan.

So Hank I would save the money on gear, and put it towards a bit more training. Don't go mad and jump straight from one course into the next (though OW->Advanced isn't out of the question), get some dives in after that, then consider the Rescue Diver course. It is one of the most rewarding on the PADI itinerary, and is a good foundation toward being a better diver able to make these sorts of judgement decisions for yourself.

As for diving in murky quarries, some of us have little choice without getting on a plane, but it can be just as rewarding ;)
 
I actually love air integrated computers, and recommend to beginners with their own regulators. In Hank's case, I think easy-to-read is the most important.

The reason why I like air integrated, is that it is really fool proof. I regularly check my SPG on my computer, and the backup real SPG occasionally, but even if I forget to check for some reason, the computer keep watching my air and warn well before running out of air.

I'm still using old Uwatec (now ScubaPro) Aladin Smart Z. The algorithm is a bit aggressive side, but as an Asian I consume less air so less risk :)
 
Hank, as someone who got certified 30 years ago, has dove all over the world, and have sometimes taken a break for a year or two, all I can tell you is to not let anyone rush you when gearing up or getting into the water, find a responsible grown up to buddy with (not easy on a boat with strangers, I know) and have them check your gear before jumping in, and don't assume the "divemaster" knows best. Some are very good, some are almost useless.
Dirk, my current dive computer is a Suunto Cobra air integrated unit. It replaced an Orca Edge that I bought in 1988. I still have the Edge, can't bear to part with it but don't use it.

I still have the Edge, it was a great computer. I was a dive master in Miami in the 80's on a boat that took 32 people. Lots of bounce diving and the edge really showed how you were absorbing nitrogen. I'll have to pull it out and see if it still works.

I agree, don't let anyone rush you, that's when mistakes happen or something gets overlooked. The guy that gave me my dive master training was a retired seal, I thought I knew how to dive before I started working with him. He kicked my ass but made me a very strong diver.
 
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Spare Air

Interesting discussion regarding spare air.

I got up to Instructor Trainer for a tech diving agency, before retirement, and our take on it was:

  1. If you are diving with a buddy, his tank (and octopus) is your backup air source. Just don't get separated from your buddy, and if you do then the dive must be called.
  2. If you are diving solo / self-sufficient, then you must carry a backup air source with you.

For divers new to the sport, the recommendation of course is #1. In particular, I would be concerned about the tendency to carry too-much equipment. I've seen my share of inexperienced divers with spare airs / pony bottles, two computers, a watch, spare mask, big bag to carry it all, and even a lunch box (seriously).

Whatever equipment you do choose, make sure you familiarise yourself with it. If you carry a spare air, make sure you include it in your pre-dive checks, and test it for real on a dive at least once a dive trip.
 
markwj; said:
  1. If you are diving with a buddy, his tank (and octopus) is your backup air source. Just don't get separated from your buddy, and if you do then the dive must be called.
  2. If you are diving solo / self-sufficient, then you must carry a backup air source with you.
Mark, sound advice, for sure. But I have read so many DAN fatality reports where rule #1 is followed "in spirit" but not in practice. Buddies get separated, they don't immediately call the dive, one runs out of air and becomes a fatality.
I appreciate that burdening a new diver with more equipment also has downsides.
 
Mark, sound advice, for sure. But I have read so many DAN fatality reports where rule #1 is followed "in spirit" but not in practice.

Yeah, very true, and that's why I qualified it with the call-the-dive statement. Sad truth is that with so much invested in dive trips (money, vacation time, ego sometimes) that it is often hard to call or postpone a dive.

Also on the earlier comment regarding ending the dive on the divemaster's octopus, I've seen that many times. However, I've got to say that it is plain wrong to do that with a diver out of air. At that point, you are his backup, neither of you have any other backup, and hence it is time to go up.

What I have done, while both leading and instructing on dives, is to go on octopus much earlier in the dive (when both had plenty of air left, but one was lower on air than the other). That is called an 'air share drill' and is fine for balancing air supplies. Also really good to practice that 'live' every now and again, so if you ever get into an emergency then you are familiar with the equipment, procedures, and your buddy.
 
So is the primary reason for this is a diver not monitoring their air and running out, or some other hardware failure?

Primary reason that I saw was higher than average air consumption, so guest running low at the end of the dive. Divemaster doesn't want to bring everyone up, so puts low on air guest on octopus.

I used to advise against this (not just for the low on air reason, but also because it makes it hard for the Divemaster to respond to other issues with the group).

As others have pointed out, a good divemaster won't let guests run out of air, as he/she will be asking them to check their gauges periodically, and have a good idea of how the guests are progressing.
 
Primary reason that I saw was higher than average air consumption, so guest running low at the end of the dive. Divemaster doesn't want to bring everyone up, so puts low on air guest on octopus.

I used to advise against this (not just for the low on air reason, but also because it makes it hard for the Divemaster to respond to other issues with the group).


I'm new at this, but that seems like a really bad idea -- what if the DM has a hardware or regulator failure, doesn't that put them both at risk of having no air backup whatsoever? Also, with two people on what's remaining of the DM's tank, how much longer would they really have to extend the dive versus calling the dive?

Also, unrelated question to dive maters running tours like this. Doesn't it get boring taking people down to the same dive sites day in and day out? What keeps it interesting?
 
I'm new at this, but that seems like a really bad idea -- what if the DM has a hardware or regulator failure, doesn't that put them both at risk of having no air backup whatsoever? Also, with two people on what's remaining of the DM's tank, how much longer would they really have to extend the dive versus calling the dive?

DMs typically breath like fishes and are often half a tank at the end of the dive, so from an air consumption basis it is fine in shallow water. But, the bigger issue is that you point out - what happens if something else goes wrong? When you have no more backup, it is time to head up.

A secondary problem is that aluminium 80 tanks are incredibly buoyant when empty, and inexperienced guests have trouble staying down in the shallow water when running on empty.

Also, unrelated question to dive maters running tours like this. Doesn't it get boring taking people down to the same dive sites day in and day out? What keeps it interesting?

I used to lead cavern tours at one of the world's top #10 ocean diving sites. Day in day out, months on end, three dives a day, and the same tour. Straight down the wall to the cavern mouth. Into the cavern daylight zone, pointing out the dolphin skeleton, turtle skeletons, flow stone, fossilised conch shell, turtle eggs, etc. Out of the cavern, and lead the divers along the wall to the safety stop area which was in a sheltered cut in the wall. I could have done it with my eyes closed. One summer, for several months that cut was full to the brim with tornados of Trevally (each about 12" to 24" long, with thousand of them grouped together). The divers would do their safety stop with this swirl of silver fish swimming around, above and below them. All in beautifully clear, blue water, with the shallow water sunlight glistening off the silver sides of the fish.

Gotta say that after months of that, what went through my head was "oh, god, not another beautiful school of Trevally". But what got me through the monotony was the small stuff. The behaviour of the small fish on the reef never ceased to amaze me. I could do 2 to 3 hours decompression in the shallow water there, and never be bored.

That, and the sight of the guest's faces when they came round the corner to the safety stop area made my day. So, if something becomes so monotonous that it can't excite you any more, perhaps the excitement you can bring out in others can inspire you.
 
tl;dr: Trip went well; Didn't see lionfish; need to dive more!

Well, I'm back from my trip to St Lucia, and it all went very well (except for one little thing I'll get to).

I arrived on a Saturday too late for diving, but went to the dive shop to sign up for Sunday's dive. On Sunday there was only one mid-morning dive. So I signed up. I think they were surprised at how prepared I was. They first noticed I was over 50 and had checked one of the aliments boxes on the medical form. "Oh, mon, you'll have to visit the doctor first to get approved for diving!" they said, would be an extra charge ($100-$150 I think). I pulled out the physical from my own doctor I got the week before who signed the PADI medical form. "Ok, so when was the last time you dived"? A year ago in Utila, I show them from my log book. "So, mon, you'll have to take the refresher course in the pool before you can go on any dive trips, that's $100!". I replied "But aha! I took the local refresher course two weeks ago, and here's my sticker on my PADI card!". Grumble, grumble, grumble, I heard from the dive shop manager. They reluctantly signed me up for the Sunday dive.

I showed up to take the bus to the marina for the dive, quite a bit apprehensive being the "noob". On the boat before we got to the dive site, I found the divemaster on the bow with the other crew divers... and as I went up to him, he was real cold, thinking something like "are you going to tell me to do my job, you rich, white, American??"... but when I actually told him I was new to diving and just certified last year, he became the most friendly and helpful guide. I think he was afraid I was some master diver going to try to tell him where to go, what to do or how to do it.

Anyway, the dive went pretty well. These are pretty easy dives, overall. On Monday thru Wednesday, there's always a 60ft dive in the morning, a short SI, and then a 40 foot dive. Pretty much everyone stays together in groups of 6 to 8. Something that kinda bugged me was there was no focus really on the buddy system, either for equipment checks onboard or while diving. While I never strayed far from the dive master, I found it a little unsettling for the equipment checks. So I just went over everything on myself 3 or 4 times to the best of my recollection (it became much easier on the later dives). I think on Tuesday on my 5th dive (out of 7 total), we were all getting ready, and I was all geared up putting my fins on, and only then realized I hadn't put my weight belt back on. (also on my 4th dive, I had put my weight belt on backwards, and didn't realize this until moments before the group started our decent.)

On the last day, we had a different dive master who did buddy us up, so I felt a little better about that.

After seeing a bunch of wildlife on the first and second days, I decided to buy a cheap $20 underwater camera to capture some of what I saw. I think I took one or two photos before diving, and it worked fine. But once I got underwater, the shutter jammed, I couldn't get it to work. I was sure I was winding the film, but it just wasn't working. Now I know what you guys mean by a distraction. I became quite distracted in trying to get it to work (I mean, how hard can it be?)... so I finally gave up after about 10 minutes of futzing with it. All the while, NOT really paying attention to the dive or wildlife. Nothing bad happened, but it's amazing how something so small became such a distraction. I can now much better see how a GoPro and/or a bailout bottle would be added distractions.

On the morning of my last day of dives, we had a good group of people on the boat. I was telling my buddy (who was somewhat of a beginner also) that all I wanted to see on this trip was a lionfish. I had 5 dives down at that point, and hadn't seen one yet. At the end of the last dive (of my trip), we all were getting back on the boat. My buddy and another guy following us with a professional camera rig said to me "did you see that HUGE lionfish??".. "No, where?" They said I swam right by it, maybe 2 to 3 feet away. It was hanging out above a big sponge coral. Nope, never saw it. They were both behind me, so they couldn't signal or point it out. The only thing I can think of is that I was swimming near the bottom and scanning the bottom for wildlife, and never really "looked up". So I must have swam by the sponge coral below the lionfish and just never saw it in my peripheral vision. The photog guy said he got some great shots of it, and I gave him my email address, but I haven't heard back from him yet. Oh well, there's always next time (we're thinking of going to Grenada in the winter). Missing the lionfish was the one little thing that didn't go well for the week, very disappointed about that. And lionfish are "everywhere" down there, I'm told.

Towards the end of my 3rd dive (a 40 footer), I accidentally became more positively buoyant than normal.. I guess I had some air in my BDC I couldn't purge. So I started ascending and couldn't stop, no matter what I tried! Once I reached the surface and was fully upright, I was finally able to purge my BCD of any extra air, and descended quickly to get back down the group. Luckily it was just a 40 foot dive and not 60. The entire event maybe lasted one minute. Interestingly, the dive computer counted that quick ascent as about 80 seconds of the safety stop. So when we ascended for the end of the dive, my computer said I only needed a 1m40s safety stop, but I stayed of course for the full 3 minutes.

On our second to last dive, we lost one member of our group all together. A woman also with limited experience had the same thing happen, except it was a 60 foot dive. Once she surfaced, she didn't attempt to join us and the boat came and picked her up. When one diver in our group counted one diver missing and alerted the DM, the DM surfaced while we waited at the bottom.. then he came back down. He didn't really convey what may have happened, or if she was OK. But we continued the dive. Only when we surfaced did her boyfriend/husband (buddy??) see her sitting on the boat safe and sound.

Only once during all seven dives did I get down to 1000psi (the announced safety zone), and that was really at the end of the dive anyway (I think about 45 minutes), so it wasn't like I was ending the dive "short."

Having the dive computer was a necessity for accurate depth and timings (thanks again Dirk!). The only thing with the DC that Dirk loaned to me (Shearwater Research Petrel) was that I couldn't really make out all the numbers in the display. I'm old, so I need reading glasses, and I even had 2.0 diopter inserts in my diving mask, which helped a lot. But even still, it was hard to read the smaller numbers/readouts on the display. Most divers (even the advanced ones) and the typical round-faced, LCD dive computers that seemed to serve their use. On one trip, one of the more experienced divers came over and asked me "hey, can you get 'Game of Thrones' on that thing???".

I know this is a long post, but "just one more thing". I didn't realize how important people treated their dive log books. I thought it was a casual thing for people to just log their dives, but it's serious stuff! The issue I have, and I think this must be nearly universal on trips like this, was when we got back to the marina, everyone was running around trying to find out the actual name/location of each dive. In St Lucia, most of the names are French based, and the locals have accents, so it's hard to hear them announce the names. Everyone was scrambling with each other to find someone with the correct info. I know there are online log books, but not everyone wants to take an ipad or electronic device with them. But still, there has to be some way for the dive shop to post immediately after (or during) the dive all the info everyone needs for their log books. I hastily scratched down what I could, and only on the very last day I had some extra time at the marina to open up the log books and record each dive's start/end time, SI, max depth, and my starting and ending PSIs. Being a technologist, it just seemed to me there had to be a better way to centralize this information and provide it to all the divers right after the dive to fill out their log books. But nope, it was just people running around with soggy log books and pens that didn't write very well.

By the end of the trip, I was much more confident than the start four days earlier. During the last couple of dives I was able to stop thinking about all the things to remember (from a technical point of view) and focus on the actual *diving* part. I'm looking forward to booking another trip.

Thanks for all your comments and suggestions!
 

Here's a photo of the lionfish I missed. Now I'm more disappointed than ever that I somehow swam right by this creature!



upload_2016-3-29_7-55-27.png

Also, I forgot to mention, once back on land I was able to figure out what was wrong with the disposable camera -- I was turning the film advance winder in the wrong direction. You'd think it's normally left-to-right with your right thumb (pretty much how you crank any normal camera).. but NO, this was right-to-left. I was sure I tried both directions while diving, but I guess not. I was able to get some photos the next day, luckily. I'll post some when I get them developed.
 

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Here's a photo of the lionfish I missed. Now I'm more disappointed than ever that I somehow swam right by this creature!


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Also, I forgot to mention, once back on land I was able to figure out what was wrong with the disposable camera -- I was turning the film advance winder in the wrong direction. You'd think it's normally left-to-right with your right thumb (pretty much how you crank any normal camera).. but NO, this was right-to-left. I was sure I tried both directions while diving, but I guess not. I was able to get some photos the next day, luckily. I'll post some when I get them developed.
Hi, Hank, great info on diving! Seemed like you had a great dive holiday in the Carribean.

Re camera, yeah, under water, we need to think everything might not work as expected. Sometimes, compressed Nitrogen cause some confusion in deep water so it is better practice everything on the shore and bring underwafer.

BTW dive computer; I'd recommend ones with large digits and display. It really helps if you are somehow too tired or went too deep (shouldn't happen, but you could).

As you make more dives you will be able to see more fish and other creatures underwater.