Life Support Equipment - Regulators

[Slonda828]

this isn't entirely true. You ever hear of an upstream design? They were not uncommon in the 1970's.

Such a design will fail by cutting off your air supply.

You are usually spot on man, but tilt valve regs were all but gone by the 70's. I have the entire run of U.S. Divers single hose regs from 1957 to 1975 and the only two tilt valve regulators that they had were the Aquadiv and Aquadiv deluxe. they were both gone before 1965. If you mean upstream as in an upstream first stage (instead of the aforementioned second stage design), there are still plenty of those around as we all know. Every diaphragm design that I have ever seen is upstream. The term upstream is sort of misleading, as it merely refers to the position of the mechanism vis-a-vis the flow of the gas. I'm not trying to nit-pick you, because you are extremely experienced. Any first stage could technically fail shut if the main spring broke at depth, but I have never heard of even one instance of that happening. I am sure it would be all over this place if it did. Note that I am only referring to tilt valves and not to pilot valve regulators, of which I am mostly unfamiliar.

Interestingly, if you ever want to try an upstream second stage (tilt valve), I have some that I have rebuilt. Breathing through one is like sucking air through a straw and they typically do not have a venturi assist.

 

[Wayward Son]

yeah, I know Posieden makes some but am not familiar with their design. Don't know if anyone else does now or not.

When I learned to dive in 1972, they were common enough that the book in my class had an explanation of both designs and what the danger of the upstream was. I just made sure to not buy one.

 

[mattmexico]

yo

being a motorcycle rider I would think so

greetings
Matt

 

[mattmexico]

yo

Inferior regulator for the dive you are going to do. I am cave diving a lot, sometimes deep to so I want a regulator that is giving me enough gas even if I have to swim a bit faster or go a bit deeper .... define deeper and faster ...

greetings
Matt

 

[mattmexico]

I read your blog article. No offense, but you might have a more realistic view of regulators if you had a better understanding of how they work rather than simply regurgitating some of the basic fallacies about regulators and continuing the fear-mongering of "life support." Your article contains several errors; balanced regs do not "compensate for environmental pressure" any differently than unbalanced regs, and unbalanced are not by design "more durable" than balanced. "Divers prefer diaphragm regs for their ease of gas delivery" is a false statement; even if you meant to say 'piston' rather than 'diaphragm' due to the higher flow capabilities of some balanced piston regs, it's still a false statement because there is no practical difference in the ability to deliver sufficient gas between diaphragm and piston regs.

I understand you are trying to send a message about how seriously you take diving and dive training, and that's understandable, but consider learning a little more about the actual topics of regulator design and performance before publishing articles about them.

Oh, and one other thing, it's misleading to students to tell them that their life depends on their regulator. In fact, it tends to negate all the training you are giving them in how to deal with equipment failure safely.

yo

Thanx, alweays happy to close an educational gap. What I do not see is how a regulator can not be a life support system. Its not scaring anybodey, its about creating awareness to choose regulators for the environment you are diving in.

greetings
Matt

 

[mattmexico]

I read your blog article. No offense, but you might have a more realistic view of regulators if you had a better understanding of how they work rather than simply regurgitating some of the basic fallacies about regulators and continuing the fear-mongering of "life support." Your article contains several errors; balanced regs do not "compensate for environmental pressure" any differently than unbalanced regs, and unbalanced are not by design "more durable" than balanced. "Divers prefer diaphragm regs for their ease of gas delivery" is a false statement; even if you meant to say 'piston' rather than 'diaphragm' due to the higher flow capabilities of some balanced piston regs, it's still a false statement because there is no practical difference in the ability to deliver sufficient gas between diaphragm and piston regs.

I understand you are trying to send a message about how seriously you take diving and dive training, and that's understandable, but consider learning a little more about the actual topics of regulator design and performance before publishing articles about them.

Oh, and one other thing, it's misleading to students to tell them that their life depends on their regulator. In fact, it tends to negate all the training you are giving them in how to deal with equipment failure safely.

Why?
.. the OP makes it sound like "inferior" regs are unsafe (at least that's what it sounded like to me)
If he does, I would like to know why he thinks this.

Me, I dive a Mk18/G250Hp .. because it was on sale at the LDS for a very good price, and also after listening to my instructors only gear buying advice given to our class ... avoid the temptation of getting a "good enough for now" entry level regulator, and to get the best performing regulator that you can afford .. not because entry level regs are unsafe, none of them are, but a good regulator can last you a lifetime of diving and you do not want to wind up wishing that you had bought a better breathing reg later

yo

Inferior in regards to the diving environment such as overhead, deep, cold not so much how much it cost ... or old.

greetings
Matt

 

[mattmexico]

Actually, regulators are designed to fail open so a failing regulator is most likely going to be free flowing. Very few reg failures are a sudden loss of air.

yo

They sure most likely do. In some environments such as overhead, deep or cold is no laughing matter.

greetings
Matt

 

[mattmexico]

Do you have any examples of this happening or are you just 'speculating'? Don't you think that the poseidon engineers thought of that?

Regarding the post about spear fisherman getting away from their buddies at depth, they are engaging in risky dive behavior if they do this without redundant gas supply. If they are injured or killed, the true cause is the risky behavior, not the regulator failure. Regulators are mechanical things, and as such can stop working.

yo

I would think a life support breathing system ( it supports my life in a hostile environment as it delivers life sustaining breathing gas to me ... and I do not have gills ) is not just a regulator but the whole system including hoses and gauges. The strangest things can happen such as mouthpice in the mouth without regulator on it, flipped exhaust valves, torn diaphragms, hoses that come out of second or first stages, second stage failure, broken and flooded pressure gauges, all kinds a o-rings that blow.

Part of the life support system on the breathing side I would think as well are valves with all their potential failure points. Not to paint it to dark, on the contrary. If you know your potential failure points you can deal with them as you prepare with choice, maintenance and going through failure scenarios mentaly and then practice them in a controlled environment.

greetings
Matt

 

[D_B]

Thanks for the replies and clearing up what you were talking about

 

[Scott L]

So a snorkel is life support equipment?

Regulators are important, clearly. They should be maintained very well, of course. But saying a regulator is "life-support equipment" amounts to creating an overly-dramatic scare tactic phrase, pure and simple.

How about life sustaining equipment?