ISO 14067 requires a product carbon footprint to be quantified consistently with the life cycle assessment standards ISO 14040 and ISO 14044, covering the single impact category of climate change, addressing biogenic carbon and land use as specific issues, reporting stored biogenic carbon separately, and excluding carbon offsetting from the footprint entirely.
Consistency with the LCA standards
ISO 14067:2018, titled “Greenhouse gases, Carbon footprint of products, Requirements and guidelines for quantification”, requires the quantification to be consistent with the life cycle assessment standards ISO 14040:2006, which sets the principles and framework, and ISO 14044:2006, which sets the requirements and guidelines. A product carbon footprint therefore follows the life cycle sequence: define goal and scope, compile the life cycle inventory, carry out the impact assessment that converts the inventory to carbon dioxide equivalent, and interpret the result. Every input, output and emission is related to a functional unit, or to a declared unit where the function is not fully specified or only part of the life cycle is assessed, in which case the result is a partial carbon footprint. carbon footprint consulting prepares and documents that footprint, while any independent critical review or verification rests with a separate competent third party.
A single impact category, and what stays outside
Unlike a full life cycle assessment that examines several impact categories, a product carbon footprint to ISO 14067 addresses one category only, climate change. The greenhouse gases carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, sulphur hexafluoride and nitrogen trifluoride are converted to carbon dioxide equivalent using published global warming potential values. Two elements are placed firmly outside the footprint.
| In scope of the footprint | Outside the footprint |
|---|---|
| Emissions and removals across the life cycle, converted to CO2 equivalent | Carbon offsetting, which shall not be included in the CFP or partial CFP |
| One impact category, climate change | Other impact categories, which belong to a full LCA |
| Reporting against a functional or declared unit | Communication of footprint claims, dealt with under separate standards |
Biogenic carbon, land use and the optional review
Several matters are handled as specific issues inside the quantification rather than ignored:
- biogenic carbon and carbon dioxide uptake;
- land use and land use change;
- soil carbon change.
Biogenic carbon stored in the product is reported separately rather than merged into a single net figure. The credibility check is a critical review, which ISO 14067 Clause 8 makes optional; where it is carried out, it follows ISO 14071. Where an independent verification of the greenhouse gas statement is required, ISO 14064-3 governs that step, performed by a competent body that did not prepare the assessment. Worked detail on inventories and emission factors sits in the carbon footprint guide.
Sources: ISO 14067:2018 · ISO 14040:2006 · ISO 14044:2006