Pardon me while I step up on my soap box... (My opinion only)
I was party to the major dog fight over background color that occurred
during amendment of IEC 1010-1. A highly-placed person on the committee
was British, from BSI I think. The BSI standard for warning signs that
originally set the black-on-yellow color was near and dear to him. Most
of the committee argued that it was too costly to demand one or two
extra colors on a product to support a single symbol, but since one
standard referenced another etc. on back to the warning sign standard,
he was unmovable. Walt Hart, formerly of FLUKE, and a few others showed
that the colors were technically only required for printed signs, that
molded markings were outside the scope of the sign standard. They
managed to force an exemption for molded markings, but were unable to
get the same exemption for printed markings. The plan was to fight it
again in the next revision, but Walt Hart retired, and I+ve moved on to
medical equipment.
Other standards do not specify colors for the symbol, and in talking to
several agencies and industry representatives, that+s the defacto
standard: few feel the color requirement is necessary.
My opinion is that, while standard colors are appropriate for a warning
sign, it should not be required for warning text on a product, where
additional colors add undue cost and can even cause distraction. The
present standard allows molded symbols to be uncolored (Thanks Walt,
et.al.), so it is inconsistent to require color on inherently more
readable printed markings. I urge those of you dealing with IEC 1010 to
push for a change allowing any contrasting colors.
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Sorry, I forgot to mention I'm using EN61010-1 "Safety requirements
for electrical equipment for measurement, control, and laboratory
use"
...
It says "symbols must be in compliance with IEC-27." but then there
is
a table that says the caution symbol is "black on yellow."
No other equipment that I can see (scopes, meters, spectrum
analyzers)
use black on yellow. They all use whatever label colors they have
available.
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***** That+s because industry is actively fighting
***** what they feel is an unjustified requirement,
***** and test houses are letting them get away with it!
