Understanding LCA and EPD Impact Categories

In this article, our LCA Consultant Helen Brown takes us on a tour of three major LCA and EPD impact category sets; EF 3.1, ReCiPe 2016 and EN15804+A2. This covers the details of each set and within this the definitions of each category, what they assess and how to interpret the resulting values. 

What are Impact Categories? 

The primary objective of the use of impact categories is to translate emissions and resource extractions into a modest number of environmental impact scores. These scores express the severity of the environmental impact within a specific impact category and can be used to quantify a product’s or process’s impact on the environment. 

They are simply factors to multiply something by, to give the environmental impact. For example, if we are looking at climate change, we could consider 20 year Global Warming Potential. For methane, the factor for this impact category is 86kgCO2e/kg¹. Therefore, the way this would work for 10kg of methane would be. 

Amount of material x factor = impact 

10kg methane x 86kgCO2e/kg = 860 kgCO2e 

When selecting impact categories, the integrative concept of sustainable development is taken as a normative framework for identifying the sustainability criteria appropriate for product being studied. Based on this concept, a certain set of impact categories is included per project. The impact categories that your product’s environmental impacts are displayed in will be defined in the goal and scope document for the LCA or EPD. 

Midpoints and Endpoints 

Before we begin, we must understand impact category terminology. Midpoint impact categories cover single environmental issues, such as global warming or water use. These feed through damage pathways into three endpoint areas: human health, ecosystems and resource availability. Endpoint results are usually easier to interpret, but that simplicity comes at a cost as this broader modelling carries more uncertainty. 

ReCiPe 2016 

Most impact category methods focus only on midpoint indicators. In contrast, the ReCiPe method ​(Huijbregts et al., 2016)​, which is a follow-up of Eco-indicator 99 and CML 2002 methods, integrates and harmonises midpoint and endpoint approach in a consistent framework ​(Margni & Curran, 2012)​.  This approach is made up of 18 midpoint categories and 3 endpoint categories. An illustrative example of how midpoints feed into endpoint categories within this methodology can be found in Figure 1.  

ReCiPe 2016 also employs three different assessment perspectives, the most popular being Hierarchist (H) which sits between the two extremes: 

• Individualist (I) represents a short time situation where technology can solve many problems and considers only proven effects. 

• Hierarchist (H) is a balance between long and short term, in a situation where it is believed that policy can avoid many problems which considers effects based on consensus. 

• Egalitarian (E) represents a very long-term situation where problems lead to catastrophe which considers all possible side effects. 

ReCiPe 2016 Impact Categories 

• Global warming (GWP100) – The product’s contribution to climate change over a 100 year horizon. This is the figure most people mean by a carbon footprint. 

• Stratospheric ozone depletion (ODP) – Damage to the high-altitude ozone layer that shields us from UV radiation, driven mainly by refrigerants, foam blowing agents and older solvents. 

• Ionising radiation (IRP) – The human health risk from radioactive releases across the life cycle, expressed relative to cobalt-60. Grid electricity is often the largest source. 

• Ozone formation, human health (HOFP) – Ground-level ozone, the summer smog that forms when volatile organic compounds react with nitrogen oxides in sunlight, assessed for its effect on people’s lungs. 

• Fine particulate matter formation (PMFP) – The potential for emissions to form fine airborne particles small enough to be drawn deep into the lungs. 

• Ozone formation, terrestrial ecosystems (EOFP) – The same ground-level ozone, this time assessed for the damage it does to plants and crops rather than to people. 

• Terrestrial acidification (TAP) – Acidification of soils by sulphur dioxide, nitrogen oxides and ammonia, which can damage plant life and forests. 

• Freshwater eutrophication (FEP) – Phosphorus reaching rivers and lakes, where it over-feeds algae and triggers blooms that strip the water of oxygen. 

• Marine eutrophication (MEP) – Nitrogen reaching coastal and marine waters, driving the same algal bloom and oxygen-loss problems at sea. 

• Terrestrial ecotoxicity (TETP) – Harm to soil-dwelling organisms from toxic substances released to land. 

• Freshwater ecotoxicity (FETP) – Harm to plants and animals in rivers and lakes from toxic substances released. 

• Marine ecotoxicity (METP) – Harm to plants and animals in seas and oceans from toxic substances released. 

• Human carcinogenic toxicity (HTPc) – The potential for the product’s emissions to cause cancer through exposure via air, water or soil. 

• Human non-carcinogenic toxicity (HTPnc) – The potential for emissions to cause non-cancer harm, such as organ damage or respiratory illness. 

• Land use (LOP) – How much land the supply chain occupies or transforms, and for how long, reflecting the natural land lost as a result. ReCiPe 2016 folds the older separate farmland, urban land and land-transformation measures into this single indicator. 

• Mineral resource scarcity (SOP) – How far the life cycle draws down finite metal and mineral ores, expressed relative to copper. A high figure points to reliance on scarcer or lower-grade ores. 

• Fossil resource scarcity (FFP) – How much oil, gas and coal the life cycle uses up, expressed as an equivalent mass of crude oil. 

• Water consumption (WCP) – The net volume of freshwater consumed and not returned to its source. 

Environmental Footprint (EF) 3.1 

The Environmental Footprint method (EF 3.1) (European Commission Joint Research Centre, 2022; Andreasi Bassi et al., 2023) was developed by the European Commission’s Joint Research Centre to standardise Product and Organisation Environmental Footprint studies across the EU (European Commission, 2021). The method operates exclusively at midpoint level, without a modelled endpoint stage (Fazio et al., 2018). It comprises 16 impact categories, several of which are split into the sub-indicators listed below. 

EF 3.1 Impact Categories 

• Acidification – Measures a product’s contribution to acid rain and acid deposition. Emissions (mainly SO₂, NOx and ammonia) react in the atmosphere and fall back to earth as acids, damaging soil, freshwater ecosystems, forests and building materials. 

• Climate change – The product’s contribution to climate change over a 100 year horizon, and the figure most people mean by a carbon footprint. 

• Climate change: biogenic – The share of the carbon footprint from biological sources, such as CO₂ released when wood, plant fibres or other organic material decomposes or is burnt. 

• Climate change: fossil – The share of the carbon footprint from fossil sources: burning coal, oil and gas, or the fossil carbon locked into materials such as plastics. For most manufactured products this is the dominant contributor. 

• Climate change: land use and land use change – The share of the carbon footprint caused by converting land from one use to another, for example clearing forest for agriculture or development, which releases carbon previously stored in soil and vegetation. 

• Ecotoxicity: freshwater – The potential harm to plants and animals living in rivers and lakes from toxic substances released. 

• Ecotoxicity: freshwater, inorganics – The share of freshwater ecotoxicity caused by inorganic substances, mainly metals released to water or soil, for example from mining, metal processing or corrosion. 

• Ecotoxicity: freshwater, organics – The share of freshwater ecotoxicity caused by organic chemicals, such as solvents, pesticides or chemical processing aids. 

• Energy resources: non-renewable – Measures how much non-renewable energy, from fossil fuels and uranium, is used up in making a product. 

• Eutrophication: freshwater – The amount of phosphorus reaching freshwater. Phosphorus over-feeds algae, causing blooms that starve the water of oxygen and harm fish and other aquatic life. 

• Eutrophication: marine – The amount of nitrogen released that can end up in marine waters, driving algal bloom and oxygen-loss problems in coastal and marine settings. 

• Eutrophication: terrestrial – Assesses nutrient enrichment on land caused by excess nitrogen, mainly from ammonia and NOx emissions. Excess nitrogen changes soil chemistry and can reduce plant biodiversity. 

• Human toxicity: carcinogenic – The potential for a product’s emissions, across its life cycle, to cause cancer in people, whether workers, nearby communities or end users. 

• Human toxicity: carcinogenic, inorganics – The cancer-related share of human toxicity caused by inorganic substances, mainly metals. 

• Human toxicity: carcinogenic, organics – The cancer-related share of human toxicity caused by organic chemicals. 

• Human toxicity: non-carcinogenic – The potential for a product’s emissions to cause non-cancer health effects, such as organ damage, respiratory illness or reproductive harm. 

• Human toxicity: non-carcinogenic, inorganics – The non-cancer share of human toxicity caused by inorganic substances, mainly metals. 

• Human toxicity: non-carcinogenic, organics – The non-cancer share of human toxicity caused by organic chemicals. 

• Ionising radiation: human health – The health risk to people from radioactive emissions across a product’s life cycle, most significantly linked to nuclear power feeding into the electricity supply used in manufacturing. 

• Land use – The impact of occupying and changing land on soil quality, covering the soil’s ability to support plant growth, resist erosion, filter water and recharge groundwater. 

• Material resources: metals/minerals – Measures how much a product depletes finite mineral and metal reserves, weighted by how scarce each resource is relative to antimony, the reference substance. 

• Ozone depletion – The potential to damage the stratospheric ozone layer (which shields us from UV radiation) mainly relevant where refrigerants, foam blowing agents or older solvents are involved. 

• Particulate matter formation – The potential for emissions to form fine airborne particles small enough to be inhaled deep into the lungs. 

• Photochemical oxidant formation – The potential to create ground-level ozone (like summer smog), which forms when volatile organic compounds react with nitrogen oxides in sunlight. Unlike the stratospheric ozone layer, which protects us, ground-level ozone is a pollutant that irritates the lungs and damages crops. 

• Water use – The net volume of water consumed (used and not returned to the source), reflecting pressure the product places on freshwater availability. 

EN 15804+A2 

EN 15804:2012+A2:2019 (CEN, 2019) is the European standard that sets the core product category rules for Environmental Product Declarations of construction products, defining how life cycle data is collected, assessed and reported across the product’s cradle-to-grave stages. The standard was amended in 2019 to bring its impact assessment in line with the European Commission’s Environmental Footprint method, replacing the seven impact categories of the earlier EN 15804+A1 with a set of indicators adopted from EF 3.1. EN 15804+A2 mandates 13 core environmental indicators and adds six further additional indicators alongside a supplementary indicator, for comparability with carbon-accounting frameworks. 

EN 15804+A2 Impact Categories 

Core Environmental Indicators 

• Climate change – total (GWP-total) – The product’s overall contribution to global warming, combining fossil, biogenic and land-use-related greenhouse gas emissions into one figure. It is the sum of the three sub-indicators below and is usually the headline carbon footprint figure. 

• Climate change – fossil (GWP-fossil) – The part of the footprint from fossil carbon: coal, oil and gas burnt for energy, plus the fossil carbon built into materials such as plastics. For most products this dominates the total. 

• Climate change – biogenic (GWP-biogenic) – The share of the carbon footprint from biological sources, such as CO2 released when wood, plant fibres or other organic material decomposes or is burnt. EN 15804+A2 requires biogenic carbon in both the product and its packaging to be reported separately. 

• Climate change – land use and land use change (GWP-luluc) – The part of the footprint from changing how land is used, such as clearing forest for farming or building, which releases carbon that soils and vegetation had stored. 

• Ozone depletion (ODP) – Captures damage to the high-altitude ozone layer that filters out UV radiation. The usual sources are refrigerants, foam blowing agents and a few older solvents. 

• Acidification potential (AP) – The product’s share of acid rain. Sulphur dioxide, nitrogen oxides and ammonia turn to acids in the air and fall back to earth, harming soils, freshwaters, forests and buildings. 

• Eutrophication potential – freshwater (EP-freshwater) – Assesses a product’s contribution to nutrient pollution in lakes and rivers, driven by phosphorus. Excess phosphorus fuels algal blooms, which strip oxygen from the water and harm aquatic life. 

• Eutrophication potential – marine (EP-marine) – The product’s contribution to nutrient pollution in seas and coastal waters, driven by nitrogen. The excess nitrogen fuels algal blooms that strip oxygen from the water and harm marine life. 

• Eutrophication potential – terrestrial (EP-terrestrial) – Nutrient enrichment of land, mainly from ammonia and nitrogen oxides. The added nitrogen shifts soil chemistry and can crowd out less competitive plants, lowering biodiversity. 

• Photochemical ozone formation (POCP) – Ground-level ozone, the main ingredient of summer smog, formed when volatile organic compounds meet nitrogen oxides in sunlight. At ground level ozone irritates the lungs and damages crops. 

• Depletion of abiotic resources – minerals and metals (ADP-minerals&metals) – How far the product draws down finite mineral and metal reserves, each weighted by scarcity against the antimony benchmark. 

• Depletion of abiotic resources – fossil fuels (ADP-fossil) – Measures how much non-renewable fossil energy, coal, oil and gas, is used up in making a product. 

• Water use (WDP) – Net freshwater taken and not returned to source, a measure of the pressure the product places on water availability. 

Additional Mandatory Indicators 

EN 15804+A2 introduced these six indicators alongside the core set, covering human health and land use effects not captured above. The standard itself treats them as mandatory for the background LCA report and optional for the EPD document, flagging them as lower robustness than the core set; many programme operators however (including the International EPD System) now require them in the published EPD. 

• Particulate matter emissions (PM) – The formation of fine airborne particles small enough to reach deep into the lungs. 

• Ionising radiation – human health (IRP) – The human health risk from radioactive releases over the life cycle, usually traced back to nuclear power in the electricity used for manufacturing. 

• Ecotoxicity – freshwater (ETP-fw) – Harm to life in rivers and lakes from toxic releases, spanning both organic chemicals and inorganic substances such as metals. 

• Human toxicity – cancer effects (HTP-c) – The potential for life-cycle emissions to cause cancer, whether in workers, neighbouring communities or the people using the product. 

• Human toxicity – non-cancer effects (HTP-nc) – The potential for emissions to cause non-cancer harm, such as organ damage, respiratory illness or reproductive effects. 

• Soil quality (SQP) – The effect of occupying and altering land on soil, covering its capacity to grow plants, resist erosion, filter water and recharge groundwater. 

3. Supplementary Indicator 

EN 15804+A2 adds a single, supplementary indicator so that EN 15804+A2 results can be compared against carbon-accounting frameworks that exclude biogenic carbon by convention, such as some corporate GHG inventories. 

• Climate change – excluding biogenic carbon (GWP-GHG) – A voluntary indicator, required by some PCRs, that is calculated identically to GWP-total except that the characterisation factor for biogenic CO2 is set to zero. This removes the uptake and release of biogenic CO2 from the figure while keeping fossil emissions, land-use change emissions and non-CO₂ biogenic gases (such as methane) in the total.  

Which Impact Category Should I Use? 

These three methodologies share the same underlying environmental science, but they diverge in the specific categories used and the methodologies used to calculate them. ReCiPe 2016 goes furthest, carrying midpoint results through to three endpoint areas so a product’s damage to human health, ecosystems and resource availability can be read on a single scale. EF 3.1 stops at midpoint level, but its harmonised category set now forms the backbone of EU environmental footprint policy. EN15804+A2 narrows the scope further still, borrowing EF 3.1’s indicators but applying them specifically to construction products, with several mandatory indicators and six more recommended by most programme operators. Which set applies to a given LCA or EPD comes down to the standard the study follows, a decision fixed at the outset in the project’s goal and scope document. 

How Below280 Can Help 

Below280 works with manufacturers and suppliers to pin down which of these three sets applies to their product carrying out fully ISO 14040/14044 compliant LCAs and EN 15804 EPDs itself, from goal and scope through to the final verified declaration. Get in touch with the team to discuss your project’s requirements.