LOL, No, I don't care to support my claim. Read the above non-sense...
How about this line: "The average DIN orings sees less dives and is changed during annual service as opposed to the yoke rental tank one that rarely gets changed unless is fails or looks really bad."
I'm pretty sure that's a regional guess. Go to Cave Country where every single tank at every single dive shop is DIN. It's a section of the country where we dive year round. Really? Less dives? That's funny.
Head to the technical operators in Pompano or Key Largo where 70% of the tanks are DIN. Less Dives Really? That's just silly.
Guys, if 2000 cave divers are using DIN, it's not for any reason except that it's safer.
Rather than just claim I am wrong, how about backing your statements up with fact, I willing to listen.. Do you really believe that tanks in cave country are dove more than tanks in a rec setting, obviously you have not seen the tank operation at a place like Buddy Dive.
But how much the TANK is dove is irrelevant, it's the use and abuse of the orings themselves are subjected too that we....well at least I am... discussing. A rental tank may see 100s of dives a year, it's unlikely any cavers reg will dive that much and if they do I would bet a good caver would service his regs if they were used that much, surely he/she would change the DIN oring at least.
It's very easy to just to poo poo someone based on what you believe but do not actually know. I spent the time to actually study how a DIN and a yoke seal work and to understand the mechanical connections was well. I am not relaying on "someone said" to base my argument on.
For cavers and others that use their regs in overhead environments DIN does have 2 major and one minor advantage. They are less likely to be rolled off and they will withstand a major strike without being knocked loose. That is why cavers use them. For rec divers those advantages are of little use since being rolled off and taking a major strike both require an overhead environment which a rec diver should not be exposed to. The minor advantage they are less prone to entanglement. While there is some truth to it, if you stop and look at all the entanglement hazards on the average tech diver....stage bottle/manifolds with 2 or 3 knobs/can lights and all the other stuff they carry, the additional entanglement hazard is real but small in the grand scheme of things.
Then there are the disadvantages of DIN valves that DIN users do not understand or at least refuse to acknowledge. DIN tank valves are relatively easy to destroy. Their side walls are thin, bump that would not hurt a yoke will crush a DIN to the point it is useless. Same goes for the reg itself, the threads are exposed, just dropping the reg on a hard object is plenty of force to damage the threads to where they will not engage the valve. At a minimum it will require some careful filing to restore the threads to a useful condition and if bad enough it will require replacement of the connection...and you need someone with a file that knows how to use it...not too likely at a dive site. Then there is the oring area of the DIN reg. It is exposed to damage from being dropped or having something dropped on it. A slight ding on the male part of the DIN near the Oring and the reg is headed back to the service tech. Compare that to the yoke, the tank valve has thicker walls and will take a lot more abuse before it is damaged beyond use. The critical surfaces on the reg are protected as well, the male sealing surface is surrounded by the yoke and reg body, the inboard threads are somewhat protected by the yoke and lastly the outboard threads are protected by a large plastic knob. Granted, they can be damaged with just the right blow but the critical surfaces of the yoke are much better protected making the likelihood of damage a lot less.
Don't get me wrong, DIN valves/regs, esp when treated with a lot of care are dependable and work well but the idea that they are somehow superior to yokes is simply not based in fact but rather a lack of understanding of the mechanical properties of both types. The idea that "cavers use them so they must be better" is a poor way to judge the actual value of a piece of dive gear.
? 
