[in reply to my concern about the weight of the yoke to DIN adapter]
Adding to the total weight is advantageous as most divers have sh!t trim anyway and any extra weight at their head will help to hopefully bring them flat.
The problem, as I see it, is that it adds a pound or more to my luggage.
300 bar capability may well be a good reason for going DIN, provided you can get good 300 bar fills.
This thread is about North America, per the title. 300 bar tanks and fills are generally unavailable here because of USDOT regulations.
Around here, no-one uses yoke. Everbody is DIN. To the chagrin of those who try to get rid of old gear that's been sitting in the basement for some years, since that gear more often than not is yoke.
In Europe, the availability of 300 bar tanks is what has driven adoption of DIN valves and regulators.
DIN often seems to be proposed as a fine solution for problems most rec. divers don't have much of (e.g.: less likely to be knocked loose if struck, capable of higher pressure connections). I dive yoke and my personal tank is a 130 cf HP steel tank; the reg. seems to handle up close to 3,400 PSI fine. I don't do cave diving.
Is knocking a yoke connection loose during a swim through on a coral reef dive, for example, at all common?
I don't know how prevalent it is. One of the drawbacks of the yoke "standard" is that there is wide variation in valves and regulators. The depth of the indentation where the clamp bolt seats is one thing that seems to vary, and it would affect the amount of force necessary to displace the regulator.
Is anyone aware of people getting tanks filled to pressures yoke reg.s can't handle, for standard recreational diving?
Many regulators are stamped with a maximum pressure on the yoke. I have some marked 4000 PSI although 3500 PSI is perhaps more common. Since USDOT regulations limit fills to 3442 PSI, the capabilities of the yoke assembly aren't limiting here for most newer regulators.
For a U.S. & Caribbean diver remaining in recreational limits, considering that diving DIN with a DIN-to-Yoke adapter seems to offer no evident advantage over Yoke, is there any significant practical advantage?
Again, you only get any benefits of a DIN regulator when you use it with a DIN tank. The adapter gives you the worst of DIN and yoke, since it has both connections, and adds its own problems with length and weight.
If the yolk is tightened down correctly then it's next to impossible to knock it loose when pressurized. You can't even come close to loosening it by hand either.
I too would be interested in any actual reports of regulators being knocked off the post during a dive.
I got back from Indonesia on Sunday. I dived with four different operators and was on boats with probably 30 other divers. DIN was everywhere. I did at least one dive where the guide was on a BP/W setup and was on a boat where two other divers (so four altogether) were on BPW/hog loop. This was all normal and unremarkable.
Right, well, DIN has widespread adoption outside North America.
I would go with a Yoke model 1st stage based on what you described above. This is what you will see most often diving in North America and the Caribbean. You do not have to mess with adapters or corroded plugs. If you remotely think that you might decide you want or need a DIN 1st stage AND you only want just one regulator you can pick a ScubaPro MK17, MK21 or MK25 1st stage. All these models can be converted from Yoke to DIN for around $100. If you like the idea of converting your 1st stage or having the ability to convert your 1st stage, buy the Scuba Pro in DIN first. It is cheaper to convert from DIN to Yoke than vise versa. I mentioned Scuba Pro Regs, because these I am familiar with their conversions. I am sure other manufactures allow their 1st stages to be converted too.
HOG has conversion parts to convert the D1 and D3 to yoke, around $40. Aqua Lung has conversions for the Titan to convert from yoke to DIN, around $65 street.
Every DIN 1st I've ever seen has the 300 bar threads. And they fit both 300 bar and 200/232 bar valves.
IME 300 bar valves are very much standard. On tanks rated for 300 bar. But never on tanks with lower pressure rating, for rather obvious reasons. Those tanks have the "old" 5-thread DIN valve rated to 232 bar.
The situation in the USA is different. When DIN valves were introduced here, they were all 300 bar and were installed on 3500 PSI (241 bar) tanks. Nearly all new DIN valves sold now are the 232 bar valves that will accept a yoke conversion slug, and these are used on cylinders rated up to 3442 PSI (237 bar). Practically all the fill stations here are set up for yoke, and have an adapter available to use for DIN. A little off topic, I've started bringing my DIN fill adapter with me when I get fills, because most fill stations only have one, and appreciate being able to fill more than one cylinder at a time if I bring them several.
