Treat every dive like a tech dive

[CuzzA]

A tech diver carries a spare mask. If you have a problem with the one you're wearing, or lose it, you take the spare out of your pocket and put it on. You need to be able to do this while holding your buoyancy at a consistent depth, as describe by John earlier.

I understand that. But a rec diver is typically never taught to carry a spare mask.

Proper weighting and a weight check should have been a part of your OW curriculum. Keep in mind, however, that the priority in most OW classes is getting you down, and it's much less time-consuming to overweight a student than it is to train them for how to dive at their optimal weight. The biggest reason why divers are overweighted is because they never learned how to descend properly. Often they inadvertently move their feet while attempting to descend, which sends them up while they're trying to go down. Or they are never taught how to use their lungs (i.e. "internal BCD") to help them descend ... particularly during that critical top few feet. And so they inhale too soon and go back to the surface before depth and compression become their friend. By the time you get to the tech level, proper weighting and doing weight checks with changes in equipment is second nature.

Good points. Yes, Proper weighting is in the text and dvd, but it's not really expanded on during the actual diving. I understand there's a time issue though. For me, I'm still trying to dial in my weight on each dive. Switching to steel tanks and colder water hasn't helped. It's been a bit frustrating.

Disconnecting a stuck inflator is a part of technical training. And there's a reason why doubles rigs are configured as they are, in order to accommodate such a failure. Yes, you should be able to swim your rig up from depth without assistance from your BCD ... it's called a "balanced rig". However, you should also be well-versed in oral inflation ... it should be no big whoop to do it if that's what the situation calls for.

I meant more in a situation were you had a wing/bladder failure. Oral inflator's not going to help. Again I guess that goes back to weighting.

In a free flow, the technical diver simply shuts down the post that the second stage is connected to ... to preserve the gas. Then you have options. You can begin an ascent, using the back-up second or you can "feather" ... turning your valve on to breathe, and then turning it off again till you need the next breath. Most times, the former, simpler option is preferable. Crimping a hose isn't typically a consideration, as that can introduce more task-loading (and a potential failure) that would only complicate the exit. Also remember, a tech diver will only need to breathe off their back gas up to the point where they can switch to their first deco gas. After that, the failure becomes inconsequential, since (unless something further goes wrong) they won't be breathing off that reg again anyway.

Totally makes sense for a tech diver. They have those options. But for the typical rec diver their only option before their tank is drained is to get to their buddy and air share or CESA to the surface while sipping air. If for whatever reason those two options aren't immediately possible I could switch to my octo and crimp the primary and I'm not losing any air. This could be especially important at the end of a dive when every cubic foot is important. I know CESA is always an option, but does anyone really want to do that in that situation when just crimping the hose will fix the problem. This isn't taught in OW.

 

[boulderjohn]

T So as a new diver, do you think those things you mentioned that can be applied to basic recreational diving can be self developed over time? That's a little bit of what I was talking about when I brought up experience. I have to believe the more you dive the better your buoyancy will become, right?

It is possible to learn calculus on your own over time, but...

1. most people prefer to learn from a skilled teacher,
2. you won't learn it if you don't do the work required to learn it,
3. you won't learn it if you don't have the educational resources for calculus instruction,
4. you won't learn it if you if you don't even know about it, and
5. you won't learn it if you don't put in the time to learn calculus specifically. It doesn't happen because you are doing a lot of adding and subtracting in your life.

Let's take back kicking. A skilled technical diver can swim backwards and thus get out of tight places without having to turn around. How many typical reef dives would have to take place before a recreational diver can do that skill? The answer is that it will NEVER happen until that diver knows it can be done, decides to learn how to do it, looks up the proper instructions for it, and practices, practices, practices, practices.

How about holding your position in a horizontal hover? The same thing is true of this as with back kicking. When I am working with students in technical training, I have a Hell of a time keeping track of them for a while because they cannot hold that position and are constantly swimming circles around me.

 

[CuzzA]

Forgive me for the editing, on a iPad trying to quote you within my post.

Just when did you take your Open Water course? These are the Standards to which I have to teach in Confined Water:

OW, was 8/1. AOW/NITROX was 11/15. Deep Diver and Advanced Recreational Trimix coming up. I'm trying to dive as much as possible, but cold fronts are really stirring up the Gulf of Mexico.

Breathe without a mask for at least one minute.
Swim without a mask for at least 15 metres/50 feet, then replace and clear the mask.

Yes for me this was in a crystal clear spring and I knew the mask was going to come back to me. I wish it had been done in Saltwater, but the weather never seems to cooperate. I want to say I may have performed a 20 foot CESA without my mask, but honestly I can't remember, could be I was just flooding my mask as I was exhaling. Lol. I'd like to do a 60 ft CESA without my mask in saltwater as that's the more likely scenario for me. But maybe this is against instructor rules? Or maybe I should save that kind of drill for when it really happens. Thoughts?

Adjust for proper weighting — float at eye level at thesurface with no or minimal air in the BCD and whileholding a normal breath.

It's done on confined water dive 2 and from then on weighting is to be adjusted at the start of the remaining confined water dives and each open water dive. Adjusting your weight under different conditions is also discussed in the knowledge development portion.

Yes. Brief weight check. But honestly, I've learned more about weighting on here than I did in class. Again, I understand time is an issue during class. I bought two steel Faber 112's and was quite shocked at the charactertics of diving them. I quickly realized during my first dive on them that I was grossly overweighted. Buoyancy characteristics of neoprene were another thing I don't recall much in depth discussion on. This is probably knit picking, but I've also read quite a bit on here about the excessive weighting of students.

Disconnect Low Pressure Inflator Hose - Have student divers disconnect the low pressure hose from the inflator in shallow water.
Orally inflate the BCD to hover for at least one minute, without kicking or sculling.

Students do learn how to deal with "runaway inflators", and how to orally inflate their BCDs underwater.

Yes. Pretty simple to disconnect the inflator, but I don't recall the inflator being pressed and me having to dump gas at the same time which is what would really be required to stop a possible uncontrolled ascent, right? Perhaps this is a safety issue for agencies and risk reward isn't worth it to them. Orally inflating a BC, no problem. No practice swimming my rig up from 60 feet with no assistance though as that could be necessary in a bladder failure. Again, I believe this goes back to weighting.

Breathe effectively from a simulated free flowing regulator for at least 30 seconds.

Purge button held fully open - it's a freeflow!

As long as there's air to breath. I would switch to my octo, crimp the primary hose and end the dive. Again, never discussed during the course.

These are skills taught in the Open Water course. I learned them in 2006 in my Open Water course and I teach them now...as part of the requirements.

I understand. Some of this is me knit picking. I guess I feel like the agency mandated training could be a little more robust. Like performing some of these skills simultaneously as could be the case during a real emergency. I know there's safety issues to deal with. I think a "boot camp" style training would be more effective. But I also understand not everyone is the same and a tourist probably wouldn't enjoy that kind of training. Perhaps this is where tech training will come into play and in that case make me a safer recreational diver.

I do however recall my AOW class being much more robust, like being hit with unexpected drills. We also had the luxury of participating in some rebreather training as a couple guys were spending time on their machines. It was pretty cool and a good experience to donate air to the guy doing a 75(?) foot swim with no air and no mask on a night dive and having to donate as he swam 25(?) feet to me without air and a mask. My 5 ft. hose definitely made that drill easier.

I'm enjoying the conversation, but it's Friday night. Enjoy the weekend.

 

[Hawkwood]

Discussions are good.

This one has gone better than a lot of them.

 

[tursiops]

I'm a bit concerned about the free-flow response of "crimp my primary hose and switch to my alternate reg" comments, made at least twice. First, the free-flow is often caused by a first-stage problem, thus affects both second stages. Second, whether crimping a hose works or not depends on the kind of hose. The older rubber one could sometimes be crimped. The newer braided ones, not so much.

 

[Kevrumbo]

Always keep a running total of how much breathing gas you have in your cylinder --you should know your pressure reading before confirming it by checking your SPG (and if you do a lot of dive travel overseas outside the US, be adept & competent in using the world standard metric system when buddied-up with Asian or European Divers).

Example:
My Surface Consumption Rate (SCR) after drift diving so many years on holiday in Palau's 28deg C tropical water temp is a personal best 11 litres/min per ATA.

Using this SCR value with a 11 litres/bar tank (i.e. an AL80 Cylinder):
Divide 11 litres/min per ATA by 11 litres/bar equals 1 bar/min per ATA .

How much easier, intuitive & advantageous is it to work with "1 bar/min" and the metric system in general for Scuba? Well, the arithmetic can all be figured easily & quickly in your head and on-the-fly:

All my dives were on Nitrox32, averaging 20 meters depth always going with the drift current; 20 meters is 3 ATA (divide 20 by 10 and add 1 gives a depth in atmospheres absolute of 3 ATA).

Therefore at 20 meters, my 1bar/min per ATA gas pressure consumption rate will increase threefold --that is 1bar/min per ATA multiplied by 3 ATA equals a depth consumption rate of 3 bar/min at 20 meters. Hence checking my elapsed bottom time every 10 minutes, I expect to consume 30 bar (3 bar/min multiplied by 10min equals 30 bar), and accordingly I already know my SPG will read 30 bar less in that 10 minute time frame. (If however the actual SPG reading indicates 30% or more consumption than expected, then there is a leak problem or I am physically exerting/breathing harder than normal and probably would consider aborting the dive).

So by the first 10 minutes delta time at 20 meters, I expect to be down 30 bar from a full AL80 tank at 200bar, or 170bar remaining actual SPG reading (3bar/min multiplied by 10min is 30bar consumed; and 30bar consumed from 200bar total full tank is the SPG showing 170bar remaining pressure). At the end of another 10 more minutes delta time drifting along at 20 meters, I've consumed 30bar from 170bar, or 140 bar remaining in tank. And finally after another 10 minute period at the elapsed dive time mark of 30 minutes total, I've consumed 30bar delta from 140bar, or 110bar remaining and nearing half tank.

40 minutes elapsed time, I'm ascending off the deep wall into the shallow coral plateau around 9 meters (down 30bar from 110bar, or 80 bar remaining in tank). And finally at the 45 to 50 minute mark, I'm at 6m and my 3-5min safety stop with 60 to 70 bar left. I surface and I know even before looking at my SPG that I have around 50 bar remaining in my tank.

This is how you should actively use your SCR with your particular tank, knowing how much breathing gas you have left not only on pre-planning, but also during the actual dive at depth, real-time-on-the-fly --all with easier to use metric units . . .additionally, you have a SPG that reads in units of pressure: why not convert your SCR to a Depth Consumption Rate (DCR) in pressure units to make use of it???

In summary & recap: divide your volume SCR (or SAC/RMV rate) by your particular tank's cylinder rating factor to get a figure in pressure units per minute since your SPG reads in pressure units -not volume units. Multiply this SCR in pressure units by your planned depth in ATA, and you'll know what your Depth Consumption Rate (DCR) per minute in pressure units at that depth will be. And the Metric System for Scuba diving makes the arithmetic much easier especially if your pressure Surface Consumption Rate (SCR) turns out to be roundable up to convenient integer like 1 or 2bar/min per ATA.

----
Some example pressure SCR values for a variety of common cylinders, given a arbitrary nominal constant volume SCR of 22 litres/min per ATA (a reasonable & achievable breathing RMV for most novice divers):

11L/bar tank (AL80): 2bar/min per ATA;
12L/bar tank (Steel HP100): 1.8bar/min per ATA;
13L/bar tank (AL100): 1.7bar/min per ATA;
15L/bar tank (Steel HP119): 1.5bar/min per ATA;
16L/bar tank (Steel HP130): 1.4bar/min per ATA.

 

[AdivingBel]

And that's SB...interesting discussion but I'm with Chilly...geez Louise...this is Basic Scuba Discussions. For the record, I'm not a "tourist" (I prefer hobbyist ) and I for one would not have appreciated a "boot camp" OW either. This is supposed to be fun.

 

[NAM001]

My point exactly.... And with commercial diving there are all sorts of rules.

... getting paid makes it a commercial dive, not a technical dive ...

... Bob (Grateful Diver)

---------- Post added December 4th, 2015 at 09:00 PM ----------

another topic to emphasize in AOW.

Always keep a running total of how much breathing gas you have in your cylinder --you should know your pressure reading before confirming it by checking your SPG (and if you do a lot of dive travel overseas outside the US, be adept & competent in using the world standard metric system when buddied-up with Asian or European Divers).

Example:
My Surface Consumption Rate (SCR) after drift diving so many years on holiday in Palau's 28deg C tropical water temp is a personal best 11 litres/min per ATA.

Using this SCR value with a 11 litres/bar tank (i.e. an AL80 Cylinder):
Divide 11 litres/min per ATA by 11 litres/bar equals 1 bar/min per ATA .

How much easier, intuitive & advantageous is it to work with "1 bar/min" and the metric system in general for Scuba? Well, the arithmetic can all be figured easily & quickly in your head and on-the-fly:

All my dives were on Nitrox32, averaging 20 meters depth always going with the drift current; 20 meters is 3 ATA (divide 20 by 10 and add 1 gives a depth in atmospheres absolute of 3 ATA).

Therefore at 20 meters, my 1bar/min per ATA gas pressure consumption rate will increase threefold --that is 1bar/min per ATA multiplied by 3 ATA equals a depth consumption rate of 3 bar/min at 20 meters. Hence checking my elapsed bottom time every 10 minutes, I expect to consume 30 bar (3 bar/min multiplied by 10min equals 30 bar), and accordingly I already know my SPG will read 30 bar less in that 10 minute time frame. (If however the actual SPG reading indicates 30% or more consumption than expected, then there is a leak problem or I am physically exerting/breathing harder than normal and probably would consider aborting the dive).

So by the first 10 minutes delta time at 20 meters, I expect to be down 30 bar from a full AL80 tank at 200bar, or 170bar remaining actual SPG reading (3bar/min multiplied by 10min is 30bar consumed; and 30bar consumed from 200bar total full tank is the SPG showing 170bar remaining pressure). At the end of another 10 more minutes delta time drifting along at 20 meters, I've consumed 30bar from 170bar, or 140 bar remaining in tank. And finally after another 10 minute period at the elapsed dive time mark of 30 minutes total, I've consumed 30bar delta from 140bar, or 110bar remaining and nearing half tank.

40 minutes elapsed time, I'm ascending off the deep wall into the shallow coral plateau around 9 meters (down 30bar from 110bar, or 80 bar remaining in tank). And finally at the 45 to 50 minute mark, I'm at 6m and my 3-5min safety stop with 60 to 70 bar left. I surface and I know even before looking at my SPG that I have around 50 bar remaining in my tank.

This is how you should actively use your SCR with your particular tank, knowing how much breathing gas you have left not only on pre-planning, but also during the actual dive at depth, real-time-on-the-fly --all with easier to use metric units . . .additionally, you have a SPG that reads in units of pressure: why not convert your SCR to a Depth Consumption Rate (DCR) in pressure units to make use of it???

In summary & recap: divide your volume SCR (or SAC/RMV rate) by your particular tank's cylinder rating factor to get a figure in pressure units per minute since your SPG reads in pressure units -not volume units. Multiply this SCR in pressure units by your planned depth in ATA, and you'll know what your Depth Consumption Rate (DCR) per minute in pressure units at that depth will be. And the Metric System for Scuba diving makes the arithmetic much easier especially if your pressure Surface Consumption Rate (SCR) turns out to be roundable up to convenient integer like 1 or 2bar/min per ATA.

----
Some example pressure SCR values for a variety of common cylinders, given a arbitrary nominal constant volume SCR of 22 litres/min per ATA (a reasonable & achievable breathing RMV for most novice divers):

11L/bar tank (AL80): 2bar/min per ATA;
12L/bar tank (Steel HP100): 1.8bar/min per ATA;
13L/bar tank (AL100): 1.7bar/min per ATA;
15L/bar tank (Steel HP119): 1.5bar/min per ATA;
16L/bar tank (Steel HP130): 1.4bar/min per ATA.

---------- Post added December 4th, 2015 at 09:17 PM ----------

Although i can empathize with your opinion , the reality is that too many with minimal OW training are set up for failure from the start. Yes it should be fun but not at the expense of your self, others or the environment. Too many have little to no regard for those aspects. 2-3 days of classroom and water time does not make a diver. OW teaches you the basics for you to build upon. If you don't build on the basics you are more a liability than an asset. Ow teaches you to survive in 60 ft and less while you learn to master skills you were taught and become comfortable. The difference between hobby and tourist? Probably if you dive twice a year on vacation or dive more regularly at home. OW does not have to be a book camp or should it be one. It does need to get the point across to the new diver that they are not masters of all waters. they have limitations and no experience. limitations they understand but ignore. Accepting inexperience unless taught with what can be done means nothing. Get that instructor in the water and have them demonstrate what a trained diver can do and students can start to realize how much there is still to learn and that they are not invincable.

And that's SB...interesting discussion but I'm with Chilly...geez Louise...this is Basic Scuba Discussions. For the record, I'm not a "tourist" (I prefer hobbyist ) and I for one would not have appreciated a "boot camp" OW either. This is supposed to be fun.

 

[Eric Sedletzky]

Well, it's just an analogy.

Driving and diving each have risks. However you might choose to measure those risks, I think it's clear that diving has greater risks, and I wonder whether the diving/instructing community could perhaps do a better job of encouraging use of the equipment and mindset that is presently associated with tech diving.

I'm old enough to remember when there were people who thought that the 3 point seat/shoulder belt harness was overkill for anything but racing. There's more tradition and less science behind our chosen safety practices (or the lack of them) than we might think.



Two different things here. Nitrox has its own risks as well as non-safety-related shortcomings and benefits which complicate the analysis.

As for going whole "hog," well, I don't know the statistics and don't presume to have the experience to offer a definitive answer. On the other hand there are accidents and near-miss narratives where a reader might conclude that a tech-oriented rig or tech-oriented mindset would have made a difference.

Get that mask off your forehead. Tec divers don't do that, no diver should do that.

 

[CptTightPants21]

Get that mask off your forehead. Tec divers don't do that, no diver should do that.
Get rid of that photo and I'll take you seriously.

Really? Can we stop with the stupid bull**** of making comments on his profile pic.

I find it interested that he has asked two or three questions and they have generated 20+ pages of comments. He's clearly new, but passionate and he doesn't talk back constantly. He has a lot of good feedback and point's of view which was the whole point of asking these questions. The sport would be better off if we had more new OW divers like him.