Writing of 24-hour clock times

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GuyBarry

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Is there any reason why 24-hour clock times in railway timetables and posters are conventionally written with no separator between the hours and the minutes? It can occasionally be confusing - the other day I read a notice saying "until approximately 1000 buses will be replacing trains", and it took me a moment to realize it didn't mean "approximately one thousand buses"! (A comma would have helped as well.) Also there's the temptation to read (e.g.) "2010" as referring to the year rather than the time.

[Edit: Just realized I've posted this to "Infrastructure" by mistake. Moderators please feel free to move it to "NR General Discussion" or wherever you feel it best belongs.]
 
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Nym

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Since I'm not arguing the semantics of the English language used on the aforementioned signs, I'll just provide some of my previously accepted implementations for notation of the 24 hour clock. All of these will be going for will indicate 5:17pm

0517P

H1717
h1717

1717hrs
1717hr

And Seventeen Seventeen Hundred Hours

Or last of all:

Bravo Charlie Niner Four Foxtrot Kilo Foxtrot Kilo.
 

LNW-GW Joint

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You see eg 17h15 a lot on the continent.
Another standard gives you "hh.mm:ss", if you need punctuation.
(I typed a colon between the minutes and seconds above, but this site interprets "colon followed by s" as a smiley! Typical of today's typographical pitalls).

Unfortunately our semi-detached metrication still gives us a mishmash.
I've recently seen the particularly awful "1005 hrs" in NR and RAIB documents.
 

D6975

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Dated trains in timetables used to have a wavy line down the middle of the column, so there wasn't any space for a colon between the two halves of the time. I wonder if this is the reason?
 

OxtedL

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You see eg 17h15 a lot on the continent.
Another standard gives you "hh.mm:ss", if you need punctuation.
(I typed a colon between the minutes and seconds above, but this site interprets "colon followed by s" as a smiley! Typical of today's typographical pitalls).
You can use [plain] and the equivalent [/nop etc.] (<nearly caught myself out there) tags, as you would with [B] and [/B] to sort this out.

I'm quite happy with reading any of the forms used above, although 05:17 pm normally catches me out as I'm expecting the redundant 0 to mean it's a 24 hour time from the morning.

It probably doesn't matter how it's written as long as it's unambiguous?
 

Mojo

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I remember when I was younger and on the Central line reading "No Service Hainault - Woodford after 2000" I thought that the line would be closed in the year 2000! :lol:

Typically when writing things I tend to always write in 24 Hr format and put a dot between the numbers (eg. "20.14"), although can understand if a colon is used instead. In training I have been told when writing service updates on station whiteboards I should write "20.14 hrs."

I can understand in timetables why there is not anything separating the four digits, and have seen 20a14, 20x14, 20s14 and 20u14 to indicate arrival times, stops on request, set down only and pick up only respectively.

Rather like OxtedL, times written like "05.17 pm" often throw me as I'm expecting a time leading with a zero to be in the morning because I commonly use the 24 Hr clock.
 

GuyBarry

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Must admit,I've never actually noticed it! But in official documents, I would write 17:03hrs.
It's been absolutely standard ever since I was a child. That's why you get these jokes like "the date is 1728, or nearly half past five". It only seems to be railway and bus companies that do it. I suppose it saves a small amount of space, but the potential for misinterpretation doesn't really seem to justify it. Many people have difficulty with the 24-hour clock in everyday contexts and I'd have thought that it would be in the interest of railway companies to make their information as clear as possible.
 

Flamingo

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We've just had a memo telling us to use 24 hr clock (and exact times) in on-board announcements and giving advice to passengers, as in "We will be arriving in Bristol Temple Meads at 1815", not "We will be arriving in Bristol Temple Meads around quarter past six".

So that's us told!
 

michael769

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As many know prior to the days of the railway Britain had no fixed time standard. In those days for most people only a rough knowledge of the time was needed ("before noon", "near sunset") so the concept of a 24-hour clock did not exist, and AM/PM was not used as it was generally self evident if it was morning or afternoon.

The 24-hour clock was first needed by the military, who in the days before radio had to send messages and plans by horserider and needed to syncronise plans some days in advance. When exactly the format was first used is not known but probably coincided with the ready availability of accurate watches and small clocks.

The original format to write "military time" was as 2000h (spoken as twenty hundred hours) and 0917h (spoken as oh nine seventeen hours).

The slightly odd and unnatural format was used because it reduced the chances of someone mistaking a time shouted over a noisy battlefield. As another advantage one could tell right away that the source was using military time and not an informal civilian time. This was very important when a fast rider might have taken over a week to deliver a message - one simply did not have the luxury of asking the sender to clarify what they meant, and any misunderstanding could potentially result in one being hanged for war crimes by ones opponent when the error allowed them to win the war.

When the railways facilitated travelling long distance at speed the deficiencies of civilian time became evident. The need for Greenwich Mean Time will be well known to anyone familiar with rail history, but the deficiencies of using civilian 12-hour time in timetables also became evident, and there was a clear need to a 24-hour time. As there was already an established official format that met the railway's needs it was adopted.

Like language time formats have changed a little over time, in common usage the "h" has been dropped and it has become the norm to use add the colon back in a a convenient but redundant separator. The real question is why timetables have followed common usage in dropping the h but not in adopting the : ? My suspicion is that it is because it saves space and allows one to cram more in without reducing the (already too small) typeface.

Even military time has moved on in its format mainly due to the need to distinguish time-zone in the modern international battlefields.

In the UK prior to the adoption of ISO 8601 in the late 1980's - which officially introduced the colon for 24hr time, it was technically incorrect to use the colon - and I suspect that many of the older hands will recognise the (then correct) 2000h format from school once reminded of it's existence.
 

Liam

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I once had a microwave which went: 23:59, 24:00, 00:01. I always thought it was strange.
 

stut

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Dated trains in timetables used to have a wavy line down the middle of the column, so there wasn't any space for a colon between the two halves of the time. I wonder if this is the reason?
Dated trains, eh? Does that mean that Northern have wavy lines on pretty much all their timetables?

;)
 

Joseph_Locke

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I once had a microwave which went: 23:59, 24:00, 00:01. I always thought it was strange.

Having worked for BR through to the end, I have been technically redundant for ten minutes of my life; 23:59 Friday to 00:01 Saturday on five seperate occasions.

I have also witnessed a near punch-up when an overzealous paybills clerk deducted the two minutes in the middle of a rare Friday / Saturday shift - the same clerk who booked a trackman off at 13:21 - one minute after the officially recorded time of death (on-site heart attack).
 

Mojo

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When the railways facilitated travelling long distance at speed the deficiencies of civilian time became evident. The need for Greenwich Mean Time will be well known to anyone familiar with rail history, but the deficiencies of using civilian 12-hour time in timetables also became evident, and there was a clear need to a 24-hour time. As there was already an established official format that met the railway's needs it was adopted.
I am interested that train timetables in both Australia and the USA still display 12 Hr clock times with ''am'' or ''pm'' in the column headings. I wonder if there is some reason why these countries have not changed over?

http://tt.metlinkmelbourne.com.au/t...ttb&outputFormat=1&contentFilter=TIMINGPOINTS

http://mta.info/lirr/Timetable/Branch/OysterBayBranch.pdf

Talking of other 'civilian' uses of the 24 Hr clock, I am often frustrated by television trailers that simply display the time of the programme without ''am'' or ''pm'' as I am occasionally unsure if they mean morning or evening.

I once had a microwave which went: 23:59, 24:00, 00:01. I always thought it was strange.
Our oven does this as well.
 

LNW-GW Joint

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Anyway, there is an ISO standard for writing dates and times, extract here.
Quite right.
I nearly posted something like this earlier but did not relish the ensuing fight with the Luddites!
Getting irritated with seeing dates like "July 4, 2012" printed in the Guardian, I complained to the Editor about using sloppy Americanisms and got a response from their Style Editor quoting an edition of the Manchester Guardian from 1836 with exactly this mode - and "if it was good enough then, it's good enough now".

Nevertheless we should try to get it right. The Swedes manage it.

Another bane is the UK/US insistance of commas separating 000s, and a dot for the decimal, while the continent uses the reverse.
ISO says to avoid confusion you can use either for the decimal, but put a half-space between the 000s.
Try that in the UK and nobody understands. But it's how it is written in eg South Africa, even in newspapers.

As for the Americans and 08.15a and 5.35p... (and 9/11).
I can't believe we printed times in bold to indicate pm times in the timetable before the BR change.
 

Flamingo

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I remember once being told to always record timings of events at midnight as 23.59 or 00.01, as timing something as 00.00 5th July for example could be taken either midnight wed-thurs, or midnight thurs-fri.
 

Trog

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I remember once being told to always record timings of events at midnight as 23.59 or 00.01, as timing something as 00.00 5th July for example could be taken either midnight wed-thurs, or midnight thurs-fri.
I was told the same thing myself as a youngster back in the early 1980's.
"Nothing on the Railway ever happens at midnight." they said, and they were right it never did.
 

Peter Mugridge

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I was told the same thing myself as a youngster back in the early 1980's.
"Nothing on the Railway ever happens at midnight." they said, and they were right it never did.
Two weeks ago, however, an engineering works poster at Epsom detailing bustitution times did include "24:00" as the time of one late night bus!
 

GB

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I don't see what all the fuss is about. If you read things in context then there is little chance of misunderstanding a time for a date.
 

stut

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Two weeks ago, however, an engineering works poster at Epsom detailing bustitution times did include "24:00" as the time of one late night bus!
Japanese timetables go a step further and have times such as 25:10 or 26:34 to indicate early morning trains that started the previous day!
 

barrykas

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Japanese timetables go a step further and have times such as 25:10 or 26:34 to indicate early morning trains that started the previous day!
Whereas we do it the other way round! Take, for example, the 23:36 from Kings Cross to Letchworth. That's shown at the start and end of the timetable (Table 24 in the eNRT).

The one at the start of the Monday to Friday table is shown as 23p36MX Kings Cross to Letchworth, with the times as far as Hatfield sporting a p between the hours and minutes, the p standing for previous night. The entry at the end of the table is shown "normally" with no such indication.

Cheers,

Barry
 

Trog

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I have to say Trog, I love your signature!

Thank-you.


The really important thing to remember of course when using the ballast minutes as toilet paper, is not to use the page with the staple in it. :shock:
 

dvboy

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Japanese timetables go a step further and have times such as 25:10 or 26:34 to indicate early morning trains that started the previous day!
The world of television broadcasting does this also, as the day starts at 6:00. A programme starting at 1:30 would be scheduled internally as 25:30.
 

DJ737

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G'day

Here in Melbourne public times for Metro are am/pm, while V/Line regional trains are in 24hr format, both systems use the same tracks and call at some of the same stations (V/Line trains stop in the 'burbs to pick up on the down and set down on the up)

EG : at Southern Cross you can have
5.00pm Craigieburn
17:05 Seymour
both trains use the same line as far as Craigieburn :roll:
Apparently most people in the Metro area run out of fingers after 1259pm, while country folk have 23:59 fingers. :lol:

Cheers
DJ737
Melbourne, Australia (home of the worlds most dysfunctional railway system)
 

cuccir

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I can understand in timetables why there is not anything separating the four digits, and have seen 20a14, 20x14, 20s14 and 20u14 to indicate arrival times, stops on request, set down only and pick up only respectively.
I think this might have a lot to do with it, although there's no reason why those annotations couldn't replace a normal :

I like the continental 11h58 format personally, but I can see why it doesn't work on railway timetables.
 
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