Protocol for the calculation of whole life cycle greenhouse gas emissions generated by asphalt

Specific contributions to climate change - “carbon footprints” - now feature in the claims of many products, giving a basis for potential customers to procure on environmental as well as economic terms. This paper describes a consistent approach to carbon footprinting devised for asphalt products, developed through a collaborative effort by the UK highways sector, with representation from clients, industry and the research community. The asphalt Pavement Embodied Carbon Tool (asPECT), which consists of protocol documentation and software, takes a life cycle approach that follows the Publically Available Specification PAS 2050:2008 and facilitates assessment of greenhouse gas contributions from raw material acquisition, through to product production, installation, maintenance and end-of-life. The method provides the resolution to allow factors such as individual constituent material contributions, recycled content, energy consumption in heating and mixing and transport modes to be reflected in the overall footprints of asphalt products and applications.