The methodology used for the Product Environmental Footprint (PEF) project is based on ISO 14040 and ISO 14044 guidelines on Life Cycle Assessments (LCAs) and in conjunction with best practice recommendations from the European Commission. It measures the different inputs needed to make a pair of shoes, e.g., raw materials, energy, water, transport, packaging. Emissions and waste are also captured for all life cycle stages from cradle to grave:
Combining expertise for a consolidated measurement standard
In order to accurately reflect the different functions and compositions of the full range of footwear products, two sub categories have been defined: Sport, leisure and fashion, and work/waterproof. Our initial calculations show that the most significant environmental impacts are similar for both shoe types. The three main ‘hotspots’ that drive the environmental performance of one shoe compared to another are:
- How raw materials used in the shoe are extracted and processed. That is, the weight and composition of a shoe directly influence the upstream burdens associated with producing polyester, nylon, cotton, rubber and leather.
- Manufacturing and Assembly: shoe sub-component processing steps (molding, forming, weaving, etc.) require energy, water, and waste. The location of these manufacturing plants also affects energy efficiency and fuel mix, a significant driver of impact across the life cycle.
- Shoe Durability: the longer a shoe lasts, the fewer replacements are needed.
Extraction and processing of raw materials
Material inputs weight by material
Identification of Tier 2 and 3 processing steps for each material
Primary packaging inputs
Inbound transport distance and mode to assembly for each material
Tier 1 and 2 manufacturing
Quantifying process electricity and thermal energy demand (specified by fuel)
Chemical inputs (solvents, glues, cleaners, etc.)
Chemical emissions (solvents to air, emissions to water, etc.)
Water inputs and outputs
Manufacturing waste disposal method
Tier 3 manufacturing
Electricity and thermal energy demand
Transport mode from factory to store
Transport distance from factory to store
Electricity and thermal energy demand
Maintenance and consumer use
Washing procedure (if recommended by brands)
DWR application (if recommended by brands)
End Of Life and disposal
Disposal method recommended by brands
Durability (standard lifetime)
Climate Change (CO2 equivalent)
Ozone Depletion (CFCs)
Particulate matter (air pollution)
Photochemical Ozone Formation (low-level air pollution)
Freshwater Eutrophication (chemical enrichment of freshwater ecosystems)
Marine Eutrophication (chemical enrichment of marine ecosystems)
Terrestrial Eutrophication (chemical enrichment of land ecosystems)
For the purposes of this pilot, the participating brands picked a sample of similar footwear products from the same product category, for example, leisure, fashion or waterproof or work-wear shoes. When it came to calculating the Environmental Scores, grades were allocated in an even distribution from A through E, so that:
- A rated footwear products have among the best environmental score of the selected pilot sample
- B rated footwear products have a better than average environmental score of the selected pilot sample
- C rated footwear products have an average environmental score of the selected pilot sample
- D rated footwear products have a poorer than average environmental score of the selected pilot sample
- E rated footwear products have among the poorest environmental score of the selected pilot sample
This is a pilot project, therefore the scores are not yet externally verified. In addition, the availability and quality of data has potential to improve and expand to cover more environmental impacts such as resource depletion, land transformation and human toxicity.
For the full details on the draft methodology, as well as data limitations and units of analysis, please see the draft PEFCR report
Ready to join the SAC?
We are building the future of the apparel, footwear, and home textiles industry, and we welcome you to join us.