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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 color-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
color-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. I t also demands that mercury is not present
in any o f the electrical or electronics components associated with labeled unit.
CFC s (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) a s 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 metal s which are Bio-accumulative.
Summary of Contents for A-17
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