watchOS 3 and the SOS Button

Apple have announced that watchOS 3 will ship with a new SOS button. Long press the button on the side of the watch to call the emergency services and an emergency contact "anywhere in the world".

An excellent feature for many reasons, it will probably be an excellent implementation too. I don't have an Apple watch so can't test the betas.

Initially I was a bit perplexed by the marketing term "works anywhere in the world". Having spent a week or two collating information for emergency number API I know that there isn't a universal dispatch number in every country. In countries where each service has a their own number - like China - how do you determine if it is a medical emergency or a "security situation" as Apple put it in the key note.

It turns out that I missed something in my research. 112 is baked into the GSM standard. In short, Mobile Station (MS) conformance specification;
Part 1: Conformance specification
(GSM 11.10-1 version 5.11.1 Release 1996)
section "26.9.6 Structured procedures / emergency call"(page 900) lists handling 112 calls as an acceptance criteria for the network. What the network does with these calls once they are connected is another matter, presumably for local telecom regulators to sort out.

Now not all networks in all countries rely on the GSM standard. As usual, in the US there are different network standards for some of the carriers, the same in China. I have not bothered to look into their specs to see if calls are handled, but it's probably safe to assume that they have some provision for it.

Now I need a way to figure out how to document this in the API.