Fundies, Bay Area/Monterey June 2010

[rhlee]

Saw this thread and wanted to clarify a few things that may be taken out of context:

1. BAUE rules are clearly posted on the club site, but are pretty much a superset of what you would find in the GUE standards as regards gas selection (END, PPO2, etc.)

2.

But in that poor vis, light pollution is less of an issue; the beams are quickly diffused by all the particulate and don't carry very far, so I've got no problem with using them constantly in those conditions. I've been known to use the highbeams on my car, too.

Is that the case for a rec dive; as gsk3 points out, no lights are even required for a rec pass, so what happens on those dives? And Rob mentioned that in tropical water he and Allison don't bother with the lights, because they can't be seen. So, if it's acceptable to dispense with passive/active light comms in that case and still be considered 'safe', why isn't it the rest of the time assuming adequate vis? I'm talking about recreational dives here, not tech dives.

As I mentioned, the primary lights are the main communication link in the team (passive & active). As the effective signalling range of those lights decreases (due to gunky conditions, super-bright ambient light, etc.), so must the team separation decrease. In the limiting case of not having any lights, you really need to almost be within arms reach, as that is your effective signalling range.

In the tropics with bright, clear water, I would bring a *bigger* light.


3.

Absolutely, and one of the things I will do at the first opportunity is to go to a depth where I can detect no signficant impairment on air/nitrox, and then switch to Tri-mix and see if there's a significant difference. Rob mentioned that he'd had to do this once, and it was as if everything suddenly snapped into sharper focus. He also mentioned that for him personally, anything under 30% He seemed to have little effect, as least far as his perceptions went. Presumably the physiological benefit was still there.

As discussed, the insidious danger of narcosis is that people don't *think* that they are impaired. I used this example from a 80-90' (IIRC) dive to motivate the point, and not as a recommended exercise. I suspect there are many folks in this forum that could add their own anecdotal evidence of relieving narcosis by turning to 30/30 or other He- based mixtures for working dives in the <100' range.

4.

Rob has to represent the agency viewpoint so I understand his answer, and I'm sure they're trying to train us for when the stops will be mandatory and we can't just blow them off. Nobody wants to emulate the Rouses. But I know what I'd do in the specific situation mentioned, and I'll make my own judgement about what's safest (as you did).

The degree to which you execute min-deco (or mandatory-deco) stops in an OOG or emergency situation may depend on the specific situation. However, it doesn't change that you should plan to have enough gas to execute the planned ascent. Recall that minimum gas is really a bare minimum, and needs to be adjusted to the capacity of the team to handle the emergency and execute the ascent in a timely fashion. Doesn't seem to make much sense to me to split hairs and shave 1min/10' off of my MG in this regard...

regards,
-Rob

 

[alwaingold]

And Rob mentioned that in tropical water he and Allison don't bother with the lights, because they can't be seen. So, if it's acceptable to dispense with passive/active light comms in that case and still be considered 'safe', why isn't it the rest of the time assuming adequate vis?

I believe what Rob said was that in tropical viz, the lights aren't as effective so we tend to stay more like arms-length away from each other. But you can see here, that we do dive with can lights even in the tropics:

Poor little crinoid being blinded by my light!

Nobody's saying that once you get your GUE card you agree never to touch air again, don a jacket BC or mount your can light to a butt plate. You just can't say that doing so is DIR.

There's been a lot of talk about DIR divers doing "non-DIR dives". Personally I think that DIR is a philosophy. I think I'm DIR on a dive even in a jacket-style BC. Maybe I am deluding myself.

Will BAUE allow us to do Ballbuster on 32% on their charter despite it being at greater than 100' END

As far as gas selection, the BAUE membership agreement says that you won't dive beyond an END of 100' +/- something (where something is at least 10 feet), and you won't dive beyond 1.4 PPO2 on the bottom. To my knowledge, it doesn't say anything about only diving standard gases. I know I've dived 21/45 on BAUE boats before.

I don't recall ever going below 100' at Ballbuster, but I have certainly dived to 110' on 32%. That is my personal hard limit, and as far as I can tell, it's not breaking any BAUE "rules". If I were planning a dive to 110' for any length of time, 32% would not be my gas of choice though.

Allison

 

[kanonfodr]

re: lights in tropical diving. For really good passive communication you're going to need a bad-ass 21w or more, there's just too much light. But at a site like Shark's Cove here on Oahu where there are numerous swim-throughs, ledges, and hidey holes for critters a powerful primary can come in very handy. It negates the need to constantly deploy and stow your backup lights or have a hand tied up with one of them.

Moving to active communication, even the tropics can suffer some blowout under the right circumstances, and having that tool at the ready really does drop the heartache involved in such a situation. Also, you can give yourself a bit more space when you are diving in a good team as everyone should be checking on everyone else constantly any way, as that bright blue dot over your hand is a real attention getter.

That being said, I don't normally dive with a primary on a daytime dive here unless we are planning some sort of penetration (shipwrecks, caverns). But at night I always have my can light, just because it gives me plenty of redundancy (1 primary, 2 backups). But in the shallows on a shore dive, with plenty of moon overhead, you can bet I will be pretty happy to kill the lights and enjoy the serenity of a lights-out swim.

Peace,
Greg

 

[Guy Alcala]

Guy,

You are being a bit of a sea lawyer here and the argument you have regarding Ballbuster is pretty weak considering that 99% of the Ballbuster site is above 100'. Is there some overwhelming need to touch the bottom at 105' when everything interesting as above you?

If I am being a sea lawyer it's because I'm trying to clarify just where a bright line is drawn, if it is. From everything I learned in class, the line is very clear: No diving air, END <= 100 feet, 32% & 30/30 MOD 100'. But when I ask about what goes on for real, I have experienced DIR divers such as Clinton and Lamont state that in fact, such dives may happen on a regular basis, which implies there's more individual interpretation allowed than I was lead to believe. I'm not talking about what I can do on dives 'outside supervision', where I can do anything I want, but those dives that are undertaken under more formal organization, such as a local GUE club.

As to wanting to go to the bottom at Ballbuster, I like going around to the backside. I find it interesting even if others don't. In good vis I've been known to lie on my back on the sand there (something I would never do on the rock on the frontside) and just watch my bubbles ascend. I picked Ballbuster for an example because it's a site that pretty much everyone local has dived, the charter boats regularly visit, and because it's just outside of the official GUE limits and is regularly dived on air or nitrox by virtually everyone, even though it's possible to be below 100' END doing so. If you wish to substitute some other site as a better example, be my guest.

The BAUE rules are very clear on the maximum END. Nobody is BAUE has the wish to play cop. There are no police who will check your gauges and mix after dives. This is not what interests people. Rec charter locations are picked based on the assumption that people will be diving the appropriate gas for them. Same for Rec3, T1 & T2 charters.

The system speaks for itself in the diving it allows us to do. There is very little willpower in the club to proslytise. People are in it for the diving not the arguments or the drama.

Which is what I'm into diving for too, so I want to know if I will get any grief from others on the same site if I choose to stretch the limits. If so, the option is to do the dive how I choose privately, as I do now. If nobody's going to give me any grief about diving that or a similar site on 32%, I'm good, because that's a reasonable mix to me.

Guy

 

[Guy Alcala]

Saw this thread and wanted to clarify a few things that may be taken out of context:

1. BAUE rules are clearly posted on the club site, but are pretty much a superset of what you would find in the GUE standards as regards gas selection (END, PPO2, etc.).

Okay, Allison's mention of +-10' being allowed by BAUE is the first I've heard of it, because that was never mentioned anywhere in the class materials or presentation as something that would be allowed/acceptable. I assumed that BAUE adhered without deviation to GUE guidelines, because standardization would require it.

2.

But in that poor vis, light pollution is less of an issue; the beams are quickly diffused by all the particulate and don't carry very far, so I've got no problem with using them constantly in those conditions. I've been known to use the highbeams on my car, too.

Is that the case for a rec dive; as gsk3 points out, no lights are even required for a rec pass, so what happens on those dives? And Rob mentioned that in tropical water he and Allison don't bother with the lights, because they can't be seen. So, if it's acceptable to dispense with passive/active light comms in that case and still be considered 'safe', why isn't it the rest of the time assuming adequate vis? I'm talking about recreational dives here, not tech dives.

As I mentioned, the primary lights are the main communication link in the team (passive & active). As the effective signalling range of those lights decreases (due to gunky conditions, super-bright ambient light, etc.), so must the team separation decrease. In the limiting case of not having any lights, you really need to almost be within arms reach, as that is your effective signalling range.

In the tropics with bright, clear water, I would bring a *bigger* light.

Rob, if I misunderstood and/or mis-quoted you, my apologies; I have no wish to put words in your mouth. My understanding of what you said that was that your 21W lights were essentially useless in those conditions, and that you had to be almost in touch contact. To me, if you're that close you should just grab your buddy and have done with it, rather than fooling around with flashing your light. Seems far quicker and simpler.

That doesn't answer the question of what pertains for purely recreational divers, who don't need to use primary lights for the class and presumably can dive afterwards without them as well. They aren't engaging in passive light comms because they aren't equipped for it (except at night), so what do they do?


3.

As discussed, the insidious danger of narcosis is that people don't *think* that they are impaired. I used this example from a 80-90' (IIRC) dive to motivate the point, and not as a recommended exercise. I suspect there are many folks in this forum that could add their own anecdotal evidence of relieving narcosis by turning to 30/30 or other He- based mixtures for working dives in the <100' range.

You didn't have to 'recommend it' as an exercise, Rob, I've long planned to do it at the first opportunity, as I've been a fair amount beyond 100' END with (as discussed in class) minimal detectable (to me) effects of narcosis other than a very slight decrease in neuromuscular coordination skills. Or so it appeared to me and my buddy who waited above me, but except for the dexterity tests I was performing to check, and the dive data I noted on my wrist slate at the time,I know we weren't in the ideal position to judge. I want to do some written tests as well (writing, math, memory) before/after the gas switch, to compare. To date, I have never encountered the sort of face-slamming, unmistakable effects of narcosis that some people have reported, but I haven't been below 138'. I'm also well-briefed on the effects of narcosis, and it may be that the behavior-modeling effect noted in the Mount-Milner test applies.


4.

The degree to which you execute min-deco (or mandatory-deco) stops in an OOG or emergency situation may depend on the specific situation. However, it doesn't change that you should plan to have enough gas to execute the planned ascent. Recall that minimum gas is really a bare minimum, and needs to be adjusted to the capacity of the team to handle the emergency and execute the ascent in a timely fashion. Doesn't seem to make much sense to me to split hairs and shave 1min/10' off of my MG in this regard...

I'll let Lamont argue this one with you.

I believe what Rob said was that in tropical viz, the lights aren't as effective so we tend to stay more like arms-length away from each other. But you can see here, that we do dive with can lights even in the tropics:

Okay. Seems a bit redundant to me as stated above, but if it works for you go for it.

<snip>

As far as gas selection, the BAUE membership agreement says that you won't dive beyond an END of 100' +/- something (where something is at least 10 feet), and you won't dive beyond 1.4 PPO2 on the bottom. To my knowledge, it doesn't say anything about only diving standard gases. I know I've dived 21/45 on BAUE boats before.

I've checked the membership application, and it says END 100' +-30', which opens things out considerably. There's a file on the BAUE site:

http://www.baue.org/procedures/standardmixes.php

stating that you dive GUE standard gases, which lists them and their MODs, and those MODs seem to conflict with the club 130' max. END limits. The only difference I saw between that file and the material presented in class was that the BAUE site gave 400' as the MOD for 10/70, while the relevant slide said 10/70 was limited to 300', with the appropriate mix used below that.

I don't recall ever going below 100' at Ballbuster, but I have certainly dived to 110' on 32%. That is my personal hard limit, and as far as I can tell, it's not breaking any BAUE "rules". If I were planning a dive to 110' for any length of time, 32% would not be my gas of choice though.

Allison

Then I'm good.

Guy

 

[lamont]

If I am being a sea lawyer it's because I'm trying to clarify just where a bright line is drawn, if it is.

In reality there are no bright clear lines when it comes to issues of deco/narcosis/ppO2s/etc.

You may have gotten some bright clear lines in your Fundies class. And there are bright clear lines in the standards. I'll still do dives around here where the max depth is 107-110-ish on a high tide because I know the sites, the conditions, the effects of narcosis on myself, know where to run for the exit, etc. I also know where my own lines are and have done scooter dives using EAN30 at 120' max depth with snot for viz and run into situations where narcosis limited the ability to do the dive I wanted to do. Somewhere in between those two lines I found my limits, which agrees fairly well with GUEs limits. So, I understand exactly why the GUE standards are the way that they are, and I agree with them entirely in the broad strokes, and if I want to modify them by +10 feet under good conditions, that's a long way from just tossing out the limits entirely and doing air dives to 190.

At your level, since you are looking for limits, GUE offers you a hard limit. If you don't know enough to analyze the suitability of those limits for yourself, you should probably stick with the limits exactly as written.

 

[Adobo]

I am so confused.

In the 3 or 4 times I have been to ballbuster on BAUE charters, I don't recall ever agonizing this much about max depth and gas choice. (Incidentally, if I am at a 100 ft and I can't see the bottom at 107 ft, is it really worth the effort to go to the bottom to touch the sand?)

I've also been to Maui twice and to Oahu once. On only one trip did I bring my can light. And I dove air pretty much the whole time.

Did I dumb down my dive planning too much?

 

[lamont]

The degree to which you execute min-deco (or mandatory-deco) stops in an OOG or emergency situation may depend on the specific situation. However, it doesn't change that you should plan to have enough gas to execute the planned ascent. Recall that minimum gas is really a bare minimum, and needs to be adjusted to the capacity of the team to handle the emergency and execute the ascent in a timely fashion. Doesn't seem to make much sense to me to split hairs and shave 1min/10' off of my MG in this regard...

After watching the video review of us dicking around on the bottom for 5 minutes, the joke in my RecTriox course was that PNW-style min deco required double-130s for recreational diving.

 

[Guy Alcala]

In reality there are no bright clear lines when it comes to issues of deco/narcosis/ppO2s/etc.

You may have gotten some bright clear lines in your Fundies class. And there are bright clear lines in the standards. I'll still do dives around here where the max depth is 107-110-ish on a high tide because I know the sites, the conditions, the effects of narcosis on myself, know where to run for the exit, etc. I also know where my own lines are and have done scooter dives using EAN30 at 120' max depth with snot for viz and run into situations where narcosis limited the ability to do the dive I wanted to do. Somewhere in between those two lines I found my limits, which agrees fairly well with GUEs limits. So, I understand exactly why the GUE standards are the way that they are, and I agree with them entirely in the broad strokes, and if I want to modify them by +10 feet under good conditions, that's a long way from just tossing out the limits entirely and doing air dives to 190.

At your level, since you are looking for limits, GUE offers you a hard limit. If you don't know enough to analyze the suitability of those limits for yourself, you should probably stick with the limits exactly as written.

Good, that's what I wanted to know. I constantly evaluate my own (and my buddy's) limits, and try to establish the edge of my personal envelope under various conditions (see my wanting to do narc checks pre/post tri-mix). I alter my dive plan depending on environmental conditions, site familiarity, etc. just as you do. My concern has been that GUE's hard limits seemed to deny me any possibility of modifying them based on my own established capabilities and knowledge. It now seems pretty clear, from what I've learned in the course of this thread, that in fact there is far more flexibility than the impression given by reading the standards and taking Fundies. And that changes my attitude towards DIR diving considerably, as it alters the balance between advantage/disadvantage.

Guy

 

[Guy Alcala]

After watching the video review of us dicking around on the bottom for 5 minutes, the joke in my RecTriox course was that PNW-style min deco required double-130s for recreational diving.

Our fundies video review showed that our min. deco ascents from 30' (once we'd finally get squared away to start) took us anywhere from 6 to 9+ minutes, just a wee bit over 30 sec. with 30 sec. slides. On the positive side, towards the end we were managing to be at the same depth most of the time and together (too much together generally, as our back kicks were very intermittent)

Guy