Lenovo T560 Manual page 40

Environmental
requirements
38
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. Mercury damages the
nervous system and is toxic in high doses. TCO'99 requirement states that batteries
may not contain more than 25 ppm (part oer million) of mercury. It also demands that
no mercury is present in any of the electrical or electronics components concerned
with the display unit. Mercury is, for the time being, permitted in the back light system
of flat panel monitors as there today 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.