FW: Australian DST abbreviations causing business problems - still

Paul Eggert eggert at CS.UCLA.EDU
Mon Jan 5 22:30:45 UTC 2009

Nigel Jones <nigjones at redhat.com> writes:

> I think the main reason you see so many "EST" results in Google is because it's
> a failed method for looking at this stuff, because it's possible you'll catch
> AEST, and your likely to catch linux users that refer to the output from 'date'
> in scripts/text/etc.

Certainly Google searches on this topic need to be viewed with a good
deal of salt.  That being said, here's another data point.  The Google
query "WST CST EST site:au" reports about 4,650 matches, almost all of
which are about Australian time zones.  The corresponding query "AWST
ACST AEST site:au" reports 675 matches, again, almost all about
Australian time zones.  This query indicates that, within Australia,
time zone abbreviations without the leading "A" are considerably more
popular than abbreviations with the leading "A".

In looking through the matches, one can easily find sources to support
all sorts of abbreviations, both from the government and from major
private organizations.  There really does not appear to be a consensus
within Australia over what the abbreviations should be.  Here are some

"Australia has three time zones. These are called Eastern Standard Time
 (EST), Central Standard Time (CST) and Western Standard Time
 (WST)--sometimes called Western Australian Time. These zones are
 sometimes referred to as AEST, ACST and AWST respectively where the
 prefix refers to Australia.
" -- Parliament of Australia, Dept. of Parliamentary Services

"Within Australia DST across the three time zones is generally denoted by
    * EDT - Australian Eastern Daylight Time
    * CDT - Australian Central Daylight Time
    * WDT - Australian Western Daylight Time
" -- Australian Government, Bureau of Meteorology

"Australian Eastern Standard Time (EST)
 Australian Central Standard Time (CST)
 Australian Western Standard Time (WST)
 Australian Eastern Summer Time (EDT)
 Australian Central Summer Time (CDT)
" -- Australian Government, Geoscience Australia

"The outage will commence at 2:00 am Eastern Standard Summer Time (ESST)
 until 3:00 am Eastern Standard Time (EST).
" -- Australian Customs Service

"NSW legislation does not specify abbreviations for standard or summer
 time. EST denotes Eastern Standard Time. Summertime or daylight saving
 time is commonly expressed as EDST (eastern daylight saving time).
" -- NSW Attorney General's Department

"All times in this schedule are in Australian Eastern Standard Time:
 add 1 hour to get Eastern Summer Time (EST).
" -- Australia Telescope National Facility, Parkes Observatory

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