[xg15]

Heard a similar story about why the german emergency number is 110 and not the easier to memorize/type 111: The latter is 3 clicks on the line with generous spacing requirements, the former 12 clicks. So 111 would be much more prone to misdialing than 110.

(I guess the international number 112 is a compromise. Still a low number of clicks, but I suppose the timing would be more difficult to get right?)

[grvbck]

Greetings from Sweden. Before switching to European standard 112 in 1996, the emergency number was… 90 000.

Three reasons for that:

1) Unlike most other countries, the Swedish dials had the number nine, and not zero, at the end. So "90 000" was considered easy to remember and easy to hit, even in the dark.

2) "90 000" was relatively easy to call by hand using the switch hook, on a telephone without a functioning number plate. (Swedish system had 1 click for zero, not 10.)

3) The statistical probability of a loose contact or some other type of electrical fault producing the sequence "90 000" is small.

[ocbyc]

If 1 click was for 0, how many clicks for 1?

[LocalH]

I would imagine 2

[grvbck]

Exactly. D+1 for every digit.

[exlurker]

Similar in Norway. One source of frequent misdiallings were from housewives dusting off the rotary phone, accidentally dialling 111.

[praptak]

111 was also easy to butt-dial on cellphones that had physical buttons.