Michael Everson wrote on 1999-10-25 18:55 UTC:
> Actually, I proposed it (see my web site). People wanted to know if it was
> really required as a stand-alone character in text, and what if anything
> its relationship was to the COMBINING RECYCLE ICON which can take numbers
> and letters inside it to (in the US) inform people of types of plastics etc.
The Möbius-loop recycling symbol is now defined in some ISO standard
that also specifies text that goes into it for material class markings
(e.g., PS4 for a certain type of polystyrene, etc.).
It was apparently originally invented by UC Berkeley art student Gary
Anderson and submitted to some contest held in 1970 by the Container
Corporation of America. It was modified by William Lloyd, then CCA
designer.
It will rarely be found in other text, but it is frequently printed,
etched, engraved, or embossed onto product components. The non-combining
version should definitely go into the symbols section, because it has
become a widely used regulatory symbol. Variants of the symbol have been
trademarked by some US states and other bodies.
The problem with making it a
COMBINING RECYCLE ICON
is exactly the same as with the existing
U+20E3 COMBINING ENCLOSING KEYCAP
There is no mechanism in Unicode to enclose more than a single
character, i.e. you can't even produce a [ESC], [Ctrl], [AltGr] or
[F4] keycap! Same for [PS] the recycle marker for polystyrene etc.
I personally think, these more complex enclosing character, which
usually have to change their size/shape based on the content should not
be part of a character set such as Unicode. The word processor should
offer a mechanism to include resizeable (i.e., parameterized) vector
graphics into documents, which can also be used for arbitrary sized
brackets, square roots, etc. All these are more graphical elements than
characters (like underlining, table rules, figures, etc), especially due
to their shape variability, and therefore clearly outside the scope of
the Unicode standard (as the combing keycap probably also should have
been).
> Perhaps you could help provide such information.
It is not any more just a US thing, but now an ISO standard, the
application of which is legally required in many European countries to
facilitate product recycling. Call ISO CS in Geneva, who can surely look
up for you the right number of the standard.
> > I've notest that there is a radioactive icon but NO RECYCLE ICON
That is also from an ISO standard (I guess ISO 361:1975, Basic ionizing
radiation symbol), and RADIOACTIVE SIGN is a somewhat naive name,
because this sign warns of ionising radiation in general, of which radio
activity is just one example (X-rays, UV light, particle beams, etc. are
others).
It would be nice if WG2 could provide better cross references to other
ISO standards when ISO 10646 contains symbols that originated in other
standards. Just do a search for "signs" and "symbols" on
http:// www.iso.ch/ and you'll get a list of the relevant documents.
Also regulatory symbols from other bodies (e.g. the EEC estimated sign)
should come with a reference to the regulation that defines its usage
and glyph shape.
Note that there are several glyph variants of this dingbat used by
different regulatory bodies. Two of the more widely used ones are shown
e.g. on
http://www.ftc.gov/bcp/conline/pubs/alerts/ecoalrt.htm
Markus
-- Markus G. Kuhn, Computer Laboratory, University of Cambridge, UK Email: mkuhn at acm.org, WWW: <http://www.cl.cam.ac.uk/~mgk25/>
This archive was generated by hypermail 2.1.2 : Tue Jul 10 2001 - 17:20:54 EDT