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#135816 - 02/08/03 11:05 PM Why 999 ?  
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
I prepared this short explanation for a friend. As we have some telecoms-interested folk in ECN, I thought it might be of passing interest to post here as well.

The British 999 emergency system was inaugurated in London on July 8, 1937, and it's on record that the first call to the new service was made at 4:20 a.m. by a householder reporting a burglar (who was later apprehended).

Why the number 999? Why not 111, 222, or some other number? There are several factors which came into play, although I've never seen a full official explanation of the choice. Some of my thoughts on the matter:

First, in the 1930s it was still held by the GPO that no valid numbers should start with a 1. (The problem being that somebody fumbling with the handset as he picked it up would accidentally send a single pulse.) Level 0 in those days was reserved solely for reaching an operator. So that left only 2 through 9 as an initial digit.

As the emergency number was to be used right across the country, it had to be fitted into all existing exchange numbering schemes with the minimum of disruption. Outside of London and the other director areas, just about all exchanges at that time started assigning numbers from level 2, e.g. local numbers may have been 214, 2539, or 20340. When level 2 was full, they proceeded to levels 3, 4, 5, etc. Having a new emergency code starting with any of those digits would have involved major changes. In these smaller exchanges, levels 6, 7, and 8 were commonly used for accessing direct trunks to neighboring exchanges (this was 20 years before long-distance dialing was introduced, but in many areas subscribers could call neighboring local exchanges automatically).

So we come to level 9, which in the 1930s was already in use for many standard service codes, for example, 91 for general inquiries, 92 for directory inquiries, 90 for telegrams etc. Many small rural exchanges were operated as satellites from a central parent exchange. As operators were stationed only at these centers, many small rural offices were already arranged such that dialing an initial 9 dropped the caller into a trunk to the parent exchange. Thus the use of 999 meant that no re-trunking was needed at all those small dependent exchanges.

Another point concerns calls originating from coin phones, or "public call offices" as they were known at that time. GPO coin phones were the pre-payment type, and the dial was inoperative until money had been deposited. Except for dialing 0 that is -- The dials on coin phones had special sets of contacts so that 0 could be dialed to reach an operator without inserting any coins. The GPO considered it important that an emergency call could be made without coins, and it wasn't too difficult to modify the dial mechanism to allow both 9 and 0 to be dialed. Had the emergency number contained ANY other digits besides 9 and 0, the task would have been made harder.

Finally, there's the question of exchange codes that were already in use in London and the other director areas (those cities with 7-digit numbering). British 7-digit numbers were of the form 3L-4N (e.g. the famous number for Scotland Yard, WHItehall 1212). Director exchanges were equipped with register translators which accepted the first three dialied digits and looked up the proper routing code to the required exchange (e.g. if the first three digits were 723 the destination office was PADdington). As the digit 9 corresponds to the letters W,X,Y, there were no exchanges in any of the director areas using the prefix 999. Thus the translators could easily be arranged to route a 999 prefix to the emergency trunks. Some other three-digit codes in director areas were also reserved for "special" use, e.g. 364 (ENG) engineering, 846 (TIM) time, etc. (The latter being the reason why some people in Britain today still talk about calling "Tim," even though the time number has long since changed -- But that's another story!)

One final point is that by choosing numbers close to one end of the dial, it becomes easy to dial in a dark or smoke-filled room. Finding the 9 hole by feel alone is much quicker than trying to count forward or back to some other digit near the middle.

[This message has been edited by pauluk (edited 02-08-2003).]

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#135817 - 02/09/03 06:08 AM Re: Why 999 ?  
Texas_Ranger  Offline
Joined: Dec 2001
Posts: 2,402
Vienna, Austria
That's interesting. In Austria all emergency numbers start with 1, but no subscriber numbers (Germany has normal subscriber numbers starting with 1). E.g. Fire department is 122, Police is 133, Ambulance 144, major automobile club hotlines are 120 and 123, time is 1503 (or if called from outside Vienna 01/1503 or 0222/1503, both area codes are in service, maybe there are time numbers in other major cities, probably the 9 state capitals). Many of these numbers are transferred to 05 area code now (local exchange tariff from all over Austria), train information used to be 1703, now it's 05/1703. I have no idea why the 0810 numbers are being replaced by 05. 0660 which used to be the same thing is now assigned as an UMTS cell phone code. Curious what they're going to do with 0662, the Salzburg area code which is lurking right in the middle of the 06x cell phone area.

#135818 - 02/09/03 09:32 AM Re: Why 999 ?  
djk  Offline
Joined: Dec 2002
Posts: 1,237
Here's a long post [Linked Image]

Ireland's numbering uses 1-XXX for special services and non geographic numbers.
Emergency Services (Fire/Ambulance/Police/Mountain Rescue/Coast Guard etc)

112 or 999 (universally available although 112 tends to override newer PABX systems and locks on mobile phones.. e.g. you can call 112 without a SIM card inserted) They're identical services. No local / individual numbers exsist for calling specific emergency services. 999 has been in operation for a LONG time and 112 is simply a mirrored service.

Calling 112 / 999 also causes a few other things to happen:
1) your line is traced (i.e. they reverse look-up the caller ID information getting your address/location)
2) you can't hang up on 999 or 112 until the operator hangs up. The exchange siezes the line.
3) All calls are recorded with the exception of specificlly sensitive calls passed through to the Police (for obvious reasons)
There is a specific Garda (Police) confidential freephone number if you need to report something annoymously.
Assistance services:

10 - Operator (eircom)
114 - International Operator (eircom)

118XX (Directory Assistance & information services, provided by competing companies) Introduced about 4 years ago at this stage.

e.g. eircom's 11-8-11 (eleven eight eleven) provides directory assistance (either a computer read number, connection or number sent out by SMS to mobiles or SMS enabled fixed line phones), talking yellow pages, lotto results, traffic reports and a load of other stuff.

11-8-50 is the main compeditor.

190X (each phone company has its helpdesk number in this range)
Phone services:
171 (voicemail almost every line in the country has at least one mailbox provided for free/almost free.)
141 - block caller ID (prefix)
142 - send caller ID (prefix)
1471 - reads back last missed call(s)
199X (line tests) e.g. 1993 reads the line number back.
Other services start with *
Special Rate numbers:

TollFree 1-800 xxx xxx
LocalRate 18 90 xxx xxx (eighteen ninty)
LoCall 18 50 xxx xxx (eighteen fifty)
1891 xxx xxx (special internet rate)
1892 xxx xxx (internet at local rate)
1893 xxx xxx (internet flat rate)

15 30 xxx xxx (most widely used 1550 "fifteen fifty")
15 90 xxx xxx (premium rate varying right up to about 2.50 (or more) euro per min.

ComReg (the regulator here) is looking into abolishing the traditional (0XX) xxx xxx dialling system and moving towards a "closed" system with no local numbers.

Right now we have a very structured geographical numbering system that is far too complicated given the size of the country and the fact that calls are increasingly charged at one national (local) rate.
The country is split into 01 (dublin) 02 (cork), 04 (Midlands and East except dublin), 05 (southeast), 06 (southwest) 07 (northwest) 09 (west)
With numbers structured as below:
(01) XXX XXXX (Dublin)
(0XX) XXX XXXX (Cork and any areas that are re-numbered)
(0XX) XXX XXX (6-digit)
(0XX) XXX XX (5-digit) (most rural areas)
(0X0X) XXX XX (5-digit) (some rural areas)

08X XXX XXXX (GSM Mobile phones) (numbers can start with 0/1 no local areas) e.g. 087 123 4567 is valid. (Mobile phone codes are simply becomming 08 XXXX XXXX with no signifigance to the numbering fairly soon. Right now 087 (vodafone) 086 (o2) 085 (meteor). Full portability of numbers within that range is on its way.
5-digit and 6-digit numbering areas are being merged making them (0XX) XXX XXXX.

The idea is to eventually harmonise it to 0XX XXX XXXX then simply remove the leading zero so we end up with XX XXX XXXX freeing up extra capacity by releasing 1 and 0 levels in local areas.

I presume the tightly structured geographical numbering is a throwback to the old Crossbar & stepXstep switching systems. I presume that with modern digital systems numbering is much more flexible.

Unlike the UK, letter codes were never used here. It's just a hierarchy of numbers..

e.g. (095) 41 222

0 (STD call) 9 (west) 5 (area within west) 4 (townland) 1222 (number which also may have geographical signifigance e.g. identify a concentrator etc)

Callers can dial 095 41 222 or just 41 222 (from within the area) it makes no difference to connection/charging both work interchangably.

Some phone companies even accept calls dialled as 00 353 XX XXX XXXX from within Ireland.

Another strange feature is that some bills now seem to identify the place you've called.
E.g. if I dial 00 44 208 the bill will Say "Outer London" or 01 "Dublin" 021 "Cork" 00331 "Paris" etc.. They used to just print the numbers.

Strange setups:

(048 = Northern Ireland. If NI number was 028 9021 9021 you would dial 048 9021 9021 from the republic (or +44 28 9021 9021) needlessly complicated but I presume it date back to the old days where they needed to route calls over the boarder rather than into Britain and back to Northern Ireland. Dialling 048 or 004428 seems to make no difference, they're both treated as "national rate" calls.

Until the early 90's you simply dialled 03 followed by the British area code (including zero) to dial the UK
e.g. Manchester was just 03051. I think similar STD arangements exsisted for calling parts of the republic of ireland from the UK.

Did such arrangements exsist elsewhere in Europe ... e.g. Germany - Austria?

The international access code was 16 for everything else. 16 44 - just got an announcement telling you to dial 03 and the british number.

#135819 - 02/09/03 10:54 AM Re: Why 999 ?  
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
In Austria all emergency numbers start with 1, but no subscriber numbers (Germany has normal subscriber numbers starting with 1).

Level 1 came into use in later years in the British system, e.g. the 91 and 92 service codes became 191 and 192, the latter still being the standard number for directory assistance today (although the 118xx alternate information providers have just been introduced here as well).

When STD (Subscriber Trunk Dialing, equivalent to American DDD) came in in the 1950s, level 0 was changed to the long-distance prefix and the number for the general operator changed to 100 (still used today). Other level 1 codes were assigned over the years, such as 151 for engineering and 17x codes for many engineering tests (ringback, cable pair ID, etc. These days whole batches of 1xxx codes are used for accessing alternate long-distance carriers, in much the same way as the 10xxx codes in the States.

Until the early 90's you simply dialled 03 followed by the British area code (including zero) to dial the UK
e.g. Manchester was just 03051. I think similar STD arangements exsisted for calling parts of the republic of ireland from the UK.

Actually, 03051 would have gotten you Liverpool. Manchester STD code was 061.

Yes, there were 000x codes for dialing into various Irish cities, e.g. 0001 for Dublin.

The Irish 048 code for dialing N.I. was introduced only recently when N.I. numbers went to 8 digits under a single area code. Under the old system, you reached N.I. with 08 plus the British STD code, e.g. 080232 for Belfast.

In pre-digital days, that kludge no doubt simplified routing and charging equipment setups. Remember that calls to N.I. from south of the border are charged only at normal Irish rates, not the same as an overseas call to the mainland U.K.

Several small European countries were closely tied to the system of a larger neighbor, e.g. Andorra/France, Liechtenstein/Switzerland.

The North American system was a little different because it covered more than just one country from the outset, but a "work around" was added by using two spare area codes for dialing into parts of Mexico, which isn't part of the North American numbering area.

[This message has been edited by pauluk (edited 02-09-2003).]

#135820 - 02/09/03 11:17 AM Re: Why 999 ?  
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
Just in case there are any international members who don't know this [Linked Image], the American emergency number is 911.

It put the small town of Hayleyville, Alabama on the map as being the first place to implement the system in 1968.

#135821 - 02/09/03 11:22 AM Re: Why 999 ?  
djk  Offline
Joined: Dec 2002
Posts: 1,237

The shortcode for northern ireland seems to be only useful if you're calling from a private payphone. Everything else recognised 004428 as national rate.

Mobile phones also have a bit of a problem as you can't roam with 048xxxxxxxx you need +4428 and I presume +35348 doesn't exsist.


Do you think that there is any advantage to scrapping local dialling and moving to 9 digit numbers in the Rep. of Ireland? other than just to give uniform lengths.

Right now there's a whole mix of lengths of numbers, similar in the uk i think?


#135822 - 02/09/03 11:43 AM Re: Why 999 ?  
djk  Offline
Joined: Dec 2002
Posts: 1,237
actually one other question..

I've noticed recently that when I call france from Ireland on an eircom line that the french ringing tone doesn't appear.. i immediately get an irish ringing tone! completely replacing the french one.

Same with calls to some US numbers.

Is this meant to happen or is it a glitch in the signaling? Seems like when the French / US system sends a signal saying it's ringing our local exchange provides its normal ringing tone. Actually makes a lot of sense from an end user perspective!

#135823 - 02/10/03 01:56 AM Re: Why 999 ?  
Trumpy  Offline

Joined: Jul 2002
Posts: 8,223
SI,New Zealand
Over here in NZ, the Emergency Number is
111, in Australia, it's 000, I think?.
It all relates, to how the old Dial phone
was set out, as in least time required to dial the required numbers.
The NZ system, blew this all out of the water, our old Dial system, went 0,1,2,3,4,5,6,7,8,9, in a clockwise direction.
Thank God, for DTMF keypads!. [Linked Image]

#135824 - 02/10/03 11:00 AM Re: Why 999 ?  
C-H  Offline
Joined: Sep 2002
Posts: 1,497
Stockholm, Sweden
>Thank God, for DTMF keypads!

That's why the European Emergency number is 112: Easy to find in the dark on a keypad.

#135825 - 02/10/03 06:17 PM Re: Why 999 ?  
djk  Offline
Joined: Dec 2002
Posts: 1,237
I thought 112 was always the German emergency number?

112 also suited most countries as the code was generally free / easily cleared for emergency use.

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