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Environmental requirements
Flame retardants
Flame retardants are present in printed circuit boards, cables, wires,
casings and housings. Their purpose is to prevent, or at least to delay
the spread of fire. Up to 30% of the plastic in a computer casing can
consist of flame retardant substances. Most flame retardants contain
bromine or chloride, and those flame retardants are chemically related
to another group of environmental toxins, PCBs. Both the flame
retardants containing bromine or chloride and the PCBs are suspected
of giving rise to severe health effects, including reproductive damage in
fish-eating birds and mammals, due to the bio-accumulative* processes.
Flame retardants have been found in human blood and researchers fear
that disturbances in foetus development may occur.
The relevant TCO'99 demand requires that plastic components weighing
more than 25 grams must not contain flame retardants with organically
bound bromine or chlorine. Flame retardants are allowed in the printed
circuit boards since no substitutes are available.
Cadmium**
Cadmium is present in rechargeable batteries and in the colour-
generating layers of certain computer displays. Cadmium damages the
nervous system and is toxic in high doses. The relevant TCO'99
requirement states that batteries, the colour-generating layers of display
screens and the electrical or electronics components must not contain
any cadmium.
Mercury**
Mercury is sometimes found in batteries, relays and switches. It
damages the nervous system and is toxic in high doses. The relevant
TCO'99 requirement states that batteries may not contain any mercury.
It also demands that mercury is not present in any of the electrical or
electronics components associated with the labelled unit.
CFCs (freons)
The relevant TCO'99 requirement states that neither CFCs nor HCFCs
may be used during the manufacture and assembly of the product.
CFCs (freons) are sometimes used for washing printed circuit boards.
CFCs break down ozone and thereby damage the ozone layer in the
stratosphere, causing increased reception on earth of ultraviolet light
with e.g. increased risks of skin cancer (malignant melanoma) as a
consequence.
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