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Información : Regulatory
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. There is however one exception. Mercury is, for the time being, permitted in the back light
system of flat panel monitors as today there is no commercially available alternative. TCO aims on
removing this exception when a Mercury free alternative is available.
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.
Lead**
Lead can be found in picture tubes, display screens, solders and capacitors. Lead damages the nervous
system and in higher doses, causes lead poisoning. The relevant TCO'99 requirement permits the
inclusion of lead since no replacement has yet been developed.
* Bio-accumulative is defined as substances which accumulate within living organisms.
** Lead, Cadmium and Mercury are heavy metals which are Bio-accumulative.
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