Produkt Category Rules (PCR)
Rules that supplement higher-level rules for life cycle assessment
What are PCRs?
Life cycle assessment is a complex issue. EPDs (Environmental Product Declarations) are generally drawn up in accordance with internationally recognised standards. The life cycle analysis of products attempts to illustrate physical material flows and define system boundaries. The results are now well known indicators: global warming potential of products and services in CO2 quantities, primary energy requirement, consumption of natural resources....
Product category rules (PCRs) are sets of rules that supplement higher-level sets of rules for the life cycle assessment (such as ISO standards).
While ISO standards must be applicable to all products that exist and are therefore kept general (or must be), construction products need rules that ensure comparability for specific products. Otherwise, the scope for interpretation and possible interpretations when calculating EPD data for the construction would be too great.
With EN 15804, a standard has existed since 2012 that regulates many areas of construction products; it can be regarded as core PCRs. Nevertheless, there are still many open issues in LCA modelling. “Vague regulations” as well as “no regulations on a topic” can mean that result values are not comparable. Even if all LCA practitioners make their assumptions to the best of their knowledge and belief, it may be that there is no “right” and “wrong” and only a “we must choose a path”.
For this reason, there are efforts in national and also international standardisation institutes and in almost all EPD programme operations to establish conventions for individual construction product categories and to ensure best possible coordination among these. The aim is to take into account process-related realities in the production of construction products, use and conditions at the end of the life cycle of construction works and products, as well as prevailing legal regulations such as waste management ordinances.
Sometimes different branches of industry have to agree and some decisions are (unfortunately) purely political or are voted on according to democratic principles.
However, when it comes to benchmarking at product or building level, the input values must be as comparable as possible.
For this reason, Bau EPD GmbH is working together with science and industry to create its own PCR rules, which it is a good idea to coordinate with PCR rules already available on the market.
At first glance, “additional rules” appear to be a hurdle, but at second glance they ensure fairness, transparency and legal certainty.