We use an independent expert company who work out the carbon footprint of the products for us. This is based on a Life Cycle Assessment which looks at the Material sourcing, Component manufacturing, Final product assembly, Product transport, Product use and End of life recovery.
The criteria it uses to measure those levels are defined by the 16 principles of impact according to the European PEF. The carbon footprint is then measured against an industry standard product and a carbon saving or increase is created. Allowing the customer to compare products on a like for like basis.