Air integration for tech dives

[Tracy]

The thing I am trying to get my arms round is what utility does it add for tech diving. So far as I can tell, nothing specific to tech diving.

I answered with my thoughts. It adds reliability. SPGs fail, spools fail, hp hoses fail. I have literal piles of broken spgs. While transmitters can and certainly will fail. Thus far, current generation transmitters have proven much more reliable in my own experience.

The people that install them on a hose, with a spool, in addition to another gauge, on a hose, with a spool. I don't really understand. It is adding more common failures and I would just run a gauge personally.
To remove a known failure point and replace with something that is less prone to failure makes sense to me and seems to work well.

I was resistant for a long time, I came around and tried it. At this point, I actually prefer it. YMMV.

 

[Tracy]

Would you / do you use transmitters on deco tanks? Or do you stick with buttons or SPG's?

I currently run spgs on all my deco/stage/bailouts. At this point, I haven't seen merit in replacing them with transmitters. Who knows what the future holds.

 

[boulderjohn]

I never understood the continuing arguments to justify why someone uses a piece of gear that someone else does not find useful.

The stage was set a couple of decades ago during debates on gear choices when some of the participants used the rhetorical strategy of grossly exaggerating the benefits of their choice and and grossly exaggerating the defects of competing choices (You're gonna die!!!!!). In offline discussions with one of the chief participants in those debates, I learned that it was (and still is today for that person in other topics of discussion) indeed a conscious rhetorical strategy. The belief was that by making it appear as if anyone who disagrees with you is a blithering moron, you are more likely to gain devoted adherents to your cause.

All evidence indicates that it works--you do get more fully devoted adherents to your cause, but you also gain fully devoted enemies as well.

 

[Adobo]

I answered with my thoughts. It adds reliability. SPGs fail, spools fail, hp hoses fail. I have literal piles of broken spgs. While transmitters can and certainly will fail. Thus far, current generation transmitters have proven much more reliable in my own experience.

The people that install them on a hose, with a spool, in addition to another gauge, on a hose, with a spool. I don't really understand. It is adding more common failures and I would just run a gauge personally.
To remove a known failure point and replace with something that is less prone to failure makes sense to me and seems to work well.

I was resistant for a long time, I came around and tried it. At this point, I actually prefer it. YMMV.

I'll take your word for it being more reliable. I have had HP spools leak before but its never been consequential. Change them out after the dive, end of story. At my most active, I never did more than 4 dives a week unless I was on vacation. On average, I would get two dives in a week and would dive 3 weekends a month.

I suppose for me, the hassle of changing out spools was next to nothing. For others who are more active, I dunno.

 

[Manatee Diver]

A couple of people have used the word shill (or the synonym "fan girl") in this thread. Not me though.

The problem with any expert's testimonial as it relates to this discussion is that I have no ability to ask details. I have no ability to ask for clarifications on why the expert thinks something. About how they came to their conclusions. And going to Shearwater's website, it's not like they are posting rebuttals to the testimonials.

Her email address is here. She may take a couple of weeks to reply, but chances are good that she will reply. And spend any decent time in Mexico you will run into her. I've chatted with her in the past.

 

[Tracy]

I'll take your word for it being more reliable. I have had HP spools leak before but its never been consequential. Change them out after the dive, end of story. At my most active, I never did more than 4 dives a week unless I was on vacation. On average, I would get two dives in a week and would dive 3 weekends a month.

I suppose for me, the hassle of changing out spools was next to nothing. For others who are more active, I dunno.

I switched the rebreather first, there is a reason. You have minimal on board gas available. You don't start dives with known leaks. SPG spools are a common leak point. Getting out at the start of the dive to go change a spool gets tiresome.
Now consider it with students, everybody has to get out of the water and wait, all geared up, while I go change a spool. While not the end of the world, it is a nuisance. If it can be avoided, why not?
Before I was teaching, I didn't run visible gauges on my rebreather, just a button gauge to check before splashing. As an instructor, I had to put gauges back on my unit. I figured I would try the technology and see how reliable it is. After two years and over 100 dives with zero failures, I replaced the gauge on my backmount rig.
Nobody says you have to do it, but for those tech divers that have changed, there was probably a fair bit of thought and trial that went into it.

 

[inquis]

I have had HP spools leak before but its never been consequential.

One of the fundamental tenets of tech diving (your expressed topic of interest) is you don't dive with a known defect. Get out of the water and replace the darn spool.

 

[Adobo]

The stage was set a couple of decades ago during debates on gear choices when some of the participants used the rhetorical strategy of grossly exaggerating the benefits of their choice and and grossly exaggerating the defects of competing choices (You're gonna die!!!!!). In offline discussions with one of the chief participants in those debates, I learned that it was (and still is today for that person in other topics of discussion) indeed a conscious rhetorical strategy. The belief was that by making it appear as if anyone who disagrees with you is a blithering moron, you are more likely to gain devoted adherents to your cause.

All evidence indicates that it works--you do get more fully devoted adherents to your cause, but you also gain fully devoted enemies as well.

Come on man.

I have 3 hobbies / past times. Every single one of them has this kind of discussion. On some topics, a set of people fall on one side of a discussion, and then another set of people fall on the other side. They debate why one way is better and the other way is not. Then occasionally, things devolve into name calling with all kinds of people feeling butt hurt.

To give an example, I do woodworking also. There is a feature developed by one manufacturer that supposedly makes table saws safer. Of course, this brand then goes for much more than other comparable table saws. Online, people argue endlessly on whether the feature is good, whether it is needed, are people going to lose fingers, on and on and on.

Point being, you make it sound like this unique in scuba. It is not.

 

[Adobo]

One of the fundamental tenets of tech diving (the OP's chief concern) is you don't dive with a known defect. Get out of the water and replace the darn spool.

I've never had a spool leak during what would have been a big dive for me. I've had them leak at the beginning of recreational dives and caught them on bubble checks.

Like I said, if he thinks transmitters are safer, I am not in possession of the relevant facts so, who am I to argue? I suspect he has also factored in other trade offs such as something protruding can get caught on line and whatever risk such a thing would have on a pitching and rocking boat. I would personally never put those things on a stage / deco bottle for that reason alone and the fact that they would give me almost no utility on those kinds of tanks only seals the deal.

 

[Wibble]

AI on the rebreather; SPG for everything else.

Reasoning:

• On a rebreather, gas is more of a secondary or tertiary piece of information
• It clears the front of the rebreather of the clutter of the two SPGs
• I had two SPGs and BOTH failed -- think the previous owner stood the box on the gauges which broke the HP hose near the SPGs
• It's really simple to see in the Nerd; gas is logged.

Bailout cylinders use SPGs. They're simple and in an emergency will be passed to other divers, therefore AI is wholly inappropriate.