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Hi Even,<br>
<br>
My understanding is that there is no specific European directive
that requires that a country use a particular offset, year round.
However, whatever the country uses, there <b>is</b> a directive
that states precisely when summertime begins and ends:<br>
<br>
<a class="moz-txt-link-freetext" href="http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:EN:NOT">http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32000L0084:EN:NOT</a><br>
<br>
This is reflected in the EU rules that European entries then
generally make use of in the database.<br>
<br>
As far as the timezone database is concerned, code does not
reference the term "Central European Time". A short name such as
"CE%sT" is not official anything but convenience, and is certainly
not unique. <br>
<br>
Eliot<br>
<br>
<div class="moz-cite-prefix">On 10/23/15 8:52 PM, Even Scharning
wrote:<br>
</div>
<blockquote cite="mid:8fc3fb37697e7df0865f4b11051ad28c@netburn.no"
type="cite">Is there an official definition of the term "Central
European Time" (CET), specifically which UTC offset(s) it refers
to?
<br>
<br>
If there is no official definition, where did the term originate
from?
<br>
<br>
I asked the information desk at the EU (Europe Direct) to help me
find links to relevant legislature, but their reply was that term
CET is "not regulated at a EU level, but internationally".
<br>
<br>
All credible sources I have found, say that CET is a constant
UTC+1. The closest thing I have found to an authoritative
document, is the German Time Act from 1978. It says: "Legal time
is Central European Time. It is defined as Coordinated Universal
Time plus one hour." There is no reference to the origin of this
definition, and no information of whether anyone other than the
Germans agree on this definition.
<br>
<a class="moz-txt-link-freetext" href="http://www.cl.cam.ac.uk/~mgk25/time/zeitgesetz.en.html">http://www.cl.cam.ac.uk/~mgk25/time/zeitgesetz.en.html</a>
<br>
<br>
On the EU's web pages (for instance
<a class="moz-txt-link-freetext" href="http://europa.eu/contact/index_en.htm">http://europa.eu/contact/index_en.htm</a>) times are usually given in
CET, not CEST (Central European Summer Time), even though daylight
saving time is currently observed. Google gives a few hundred
thousand results for CET on europa.eu, and numerous of these
results are hits on dates in the daylight saving time period.
<br>
<br>
I think it makes more sense to define CET as alternating between
UTC+1 (standard time) and UTC+2 (when DST is observed). (See
<a class="moz-txt-link-freetext" href="http://time.is/CET">http://time.is/CET</a> for a more elaborate definition.)
<br>
<br>
This is in line with for instance the US time zones Pacific Time
and Eastern Time, which refer to the time currently observed,
whether it is standard time or daylight saving time.
<br>
<br>
Even Scharning
<br>
Time.is - exact time for any time zone
<br>
<a class="moz-txt-link-freetext" href="http://time.is/">http://time.is/</a>
<br>
<br>
<br>
</blockquote>
<br>
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