Ozone Depleting Substances
Smiths uses small quantities of ozone depleting substances such
as CFCs and HCFCs in its operations. Typical applications include
air conditioning and refrigeration systems such as environmental
test chambers for aerospace products, process cooling, precision
cleaning and fire fighting systems.
Emissions to atmosphere occur through small losses that result
from equipment maintenance, accidental leakage and the use of
HCFC-141b solvent in precision cleaning of aerospace components.
Our use of HCFC-141b is permitted under the Montreal Protocol
and EC Regulations until 2008. Absolute emissions of these substances,
expressed as tonnes of CFC-11 equivalent, have reduced by 47
per cent over the last three years. The companies sold during
2003 made a negligible impact on our reduction of emissions
of ozone depleting substances during the year.
VOC Emissions
Smiths recognises that emissions of volatile organic compounds
(VOCs) have environmental impact and monitors their use in operations.
VOC emissions arise from the use of solvents in applications
such as the precision cleaning and degreasing of components,
in adhesive or bonding operations and in surface coatings and
painting.
Estimates of VOC emissions from solvent use are derived from
air monitoring data or mass balance calculations. In the absence
of this information, it is assumed that all solvent used in a
given year is emitted to atmosphere as VOCs. This will therefore
tend to overestimate emissions.
After allowance is made for the businesses divested in 2003,
VOC emissions were virtually unchanged compared with 2002. Within
this figure, the Smiths Detection business in Toronto released
12 tonnes of VOCs during the year (one tonne in 2002) as part
of a significant increase in production volumes for Ionscan explosives
detectors. Emissions of VOCs, expressed as kg/£million
sales decreased by 12 per cent compared with 2002.
Smiths has directed significant effort into minimising the use
of solvents, thus reducing our emissions of VOCs through process
elimination, by switching to aqueous or citrus-based cleaners
and in re-distilling waste solvent for re-use.
Reducing Solvent Use for PCB Cleaning
Smiths Aerospace Electronic Systems – Cheltenham,
reduced the use of prozone solvent in cleaning printed circuit
boards, by changing the way the boards are loaded into the vapour
degreasing tank, from the horizontal to the vertical plane. This
resulted in 50% less solvent being trapped on the surface of
the board when taken out of the tank, with zero cost to the business. |
