Notice: This blog piece was created prior to the formation of the British Precast Drainage Association.

Posted by & filed under Sustainability.

The practice of carbon accounting for pipeline products and sewerage construction projects is not new, but PAS 2080 introduces something new. In this blog we identify how five carbon accounting principles in PAS 2080 will change the sector’s understanding of embodied carbon.


Many water companies, highway authorities, other drainage infrastructure asset owners and supply chain partners already employ project carbon calculators. However, there are significant differences between these tools. PAS 2080 introduces a structured approach to tackle this inconsistency problem: It also provides clear boundary rules and a framework for whole life carbon accounting based on European standard EN 15978 where carbon claims can be verified and low carbon solutions can be robustly assessed.

PAS 2080 could mark the end of unproven claims for manufacturers of pipeline products. Data sources such as the Bath University ICE database will no longer be the main source of embodied carbon data. For manufacturers, PAS 2080 introduces five main principles which will change how embodied carbon is dealt with: These are

  • Consistency in methodology
  • The ‘Cradle-to-Grave’ approach
  • Data Quality Requirements
  • Third party accreditation
  • Data challenging and re-baselining


Consistent Methodology

PAS 2080 states “Consistent methodologies and data sources for carbon management and assessment are to be used to allow comparisons of emissions over time”. Users are obliged to assess inconsistencies and continuously challenge their suppliers for more accurate and robust data. The standard doesn’t embrace a specific methodology but European standard EN 15978 indicates that the European Commission’s TC350 methodology is probably the route to be taken by any future revision of PAS 2080. This means that the Bath University ICE Database may no longer be an automatically valid option as it compiles carbon values from a wide range of studies that are not aligned to EN 15978 requirements.



Cradle to Grave

PAS 2080 also stresses that any carbon quantification for assets (such as pipelines) needs to consider whole life using the EN 15978 modular approach (see Fig 1). The PAS guidance goes further and specifies “120 years” as the target service duration of an asset. This will require the different components of such assets (e.g. pipes, manholes) to serve for such period or be replaced/ renovated. PAS 2080 also refers to ISO 15686 series to prove assets and components service life values: This means that only proven and substantiated working service life claims can be accepted.

There is acceptance for such working service life for concrete drainage products through a combination of national standards (Highway authority specifications, BS 8500, BRE Special Digest SD-1, etc.) and European standards (EN206, Eurocodes).

Products manufactured to CEN standards or holding third party certification such as BBA Certificates explicitly claiming no more than 50 years of guaranteed service life will have to be treated differently as these products will need to be replaced or renovated a number of times during a 120 years period.


Data Quality Requirements

PAS 2080 introduces a number of measures, taken directly from the ISO 14040’s Life Cycle Assessment book, to ensure data quality. Any data used for carbon quantification needs to be relevant in terms of age, geography and technology. It needs to come from a consistent quantification methodology and any uncertainty in data will need to be assessed and dealt with if necessary. Although the Guide to PAS 2080 lists the ICE database as a possible source for generic data, the footprinting values within that database cannot be accepted directly at face value and may need further assessment and amendment to make it more appropriate. There are already datasets for concrete and plastic pipes at the ICE database, but the quality requirements and methodologies used in these datasets are significantly different. Both datasets can change significantly if a single consistent methodology such as Environmental Product Declarations (EPD) compliant with EN 15804 is used:

  • Concrete pipe footprints will need to employ new cement data (as data from 2007 will be taken as old)
  • HDPE pipe footprint will need an overhaul of its source dataset (Plastics Europe) to align it with EN 15804 rules on allocation (Plastics Europe use mass allocation for some stages of ethylene production), age (some datasets are from 1990’s), and geographic representation (resin imported from Middle East/ Asia for UK pipe manufacture not represented).


3rd party accreditation

Manufacturers of construction products are expected to back their claims with 3rd party accreditation if asked to. This will potentially raise the standards within the sector. The fact that consistency is needed to enable fair comparisons should mean that levels of 3rd party accreditation across product footprints will need to be equivalent:

For example, a product carbon footprint from an EPD developed using an established certification scheme such as BRE or IBU cannot be directly compared with a quantification using ISO 14065, which is an organisation-based quantification standard with lax requirements on Scope 3 carbon emissions and not an established product-based footprint standard.


For most users, it is expected that baselines under PAS 2080 will be based on generic data from the most used datasets in the sector, currently the ICE database. However, PAS 2080 encourages baselines to be challenged and amended. This is clearly in anticipation of EPDs developed to EN 15804 which will change the perceptions and understanding of embodied carbon for construction products where all footprints will be compared under the same set of rules.


Credited to: Hafiz Elhag, Sustainability Manager, British Precast

Leave a Reply

  • (will not be published)