Description of the environmental impact categories in EPDs.
GWP – Global Warming Potential:
Greenhouse gases contribute to global warming. Human activity increases the concentration of greenhouse gases in the atmosphere. In order to be able to compare the warming effect of greenhouse gases, the researchers have arrived at a unit of measurement called global warming potential. GWP indicates accumulated warming power relative to CO 2 over a selected period of time.
A 100-year time horizon is usually used and the units are referred to as CO 2 equivalents.
GWP is divided into 4 indicators, GWP total, GWP fossil, GWP biogenic and GWP luluc
GWP Total – the sum of fossil, biogenic and luluc
GWP Fossil The GWP fossil indicator takes into account the GWP of greenhouse gas emissions and sequestration in all media resulting from the oxidation or reduction of fossil fuels or fossil carbon-containing substances (e.g. combustion, landfilling, etc.). This indicator also includes the binding or emission of greenhouse gases in inorganic materials (e.g. calcination, carbonation of cement- or lime-based building materials).
GWP Biogenic – Carbon dioxide released as a result of the combustion or decomposition of organic material
Negative = Stored in product Positive = emissions due to decomposition / combustion
The indicator “GWP-biogenic” takes into account the amount of CO2 absorbed from the atmosphere during the growth of biomass and bound over the lifetime of the material, as well as biogenic emissions to air through oxidation or decay of biomass (e.g. combustion). Transfers of biogenic carbon from previous product systems into the product system under investigation or transitions into subsequent product systems (e.g. wood recycling) must also be taken into account.
The uptake of biogenic CO2 into biomass and transitions from previous product systems must be presented in the life cycle assessment as a negative value (-1 kg CO2-equ./kg CO2), emissions of biogenic CO2 from biomass and transitions from biomass into subsequent product systems must be characterised as a positive value (+1 kg CO2-equ./kg CO2).
GWP Luluc – land use and land use change
The GWP luluc takes into account greenhouse gas emissions and bonds (CO2, CO and CH4) that arise in connection with changes in the specified carbon stock as a result of land use and land use change.
Some common emissions of gases that may contribute to GWP are given in the table below.
| Emissions | Chemical formula | Conversion factor (IPCC 2007) | Unit | Typical emissions from: |
| Carbon dioxide | CO2 | 1 |
kg CO2 eq. / kg |
|
| Methane | CH4 | 36,75 | kg CO2 eq. / kg |
|
| Nitrous oxide | N2O | 298 | kg CO2 eq. / kg |
|
ODP – Stratospheric ozone depletion (ozone layer)
Ozone depletion potential
The ozone layer, is the altitude range in the atmosphere where one finds a significant concentration
of ozone, and where this gas plays a significant role in regulating radiation
from the sun.
Halogen radicals such as atomic chlorine, Cl, and bromine, Br, are highly reactive and contribute
for ozone depletion. The same goes for natural sources such as microbiological processes
and combustion processes on Earth. Potential for degradation of stratospheric
ozone is expressed in kg CFC-11 equivalents in EPD.
AP– Acidification
Acidifikation potentional
The environmental impact, Acidification, is a measure of potential contribution to increased acidity from various sources. Acidification occurs due to, for example, air pollution, acid rain and emissions of ammonia from agriculture. Acidification is known to damage lakes and rivers with lethal effects on algae, fish and microorganisms, but also terrestrial organisms such as plants and animals can be damaged. Almost all plant species have a defined optimal level of acidity. A large deviation from this level is harmful.
Acidic precipitation can dissolve important nutrients such as potassium and calcium, making them less accessible to plants. It can also dissolve and increase the availability of toxic metals such as aluminum and mercury.
Several substances can contribute to acidification. Here, too, a factor is used that describes how much the substances can contribute in relation to a reference substance. Acidification is measured in kg SO 2 equivalents. Three important emissions that can contribute to acidification are given in the table below.
| Acidifying emissions | Chemical formula | Conversion factor | Unit | Important sources |
| Sulfur dioxide | SO2 | 1,2 | kg SO2 eq. / kg | Combustion of heavy fuel oils Sulfur emissions from industry |
| Ammonia | NH3 | 1.6 | kg SO2 eq. / kg | From the industry From agriculture |
| Nitrogen oxides | NOx | 0.76 | kg SO2 eq. / kg | From combustion of fuel From biomass (plants) Different series of different production processes. |
EP – Eutrophication potential
Eutrophication potential
Eutrophication is increased plant production caused by increased supply of nutrients. Eutrophication leads to an increase in the primary production of planktonic algae in the summer, often with mass blooms of some species, and subsequent loss of oxygen at the bottom where the biomass decomposes. Oxygen depletion in the groundwater can lead to further release of nutrients from the sediments, accumulated over a long period of time through natural processes.
EP is divided into 3 different indicators, EP Freshwater, EP Marine, EP Terrestrial.
EP-FreshWater – Eutrophication freshwater
Unit = kg P -eq
Eutrophication potential, fraction of nutrients reaching freshwater end compartment.
EP-Marine – Eutrofiering potensial i havet
Unit = kg N -eq
EFor marine ecosystems, aquatic eutrophication through the entry of nitrogen (N) compounds via air and water is decisive.
EP-Terrestrial – Eutrofiering av jordsmonnet (terrestrisk)
Unit = mol N eq.
For terrestrial eutrophication the inputs of nitrogen via the air in the form of ammonia (NH3) and nitrogen oxides (NOx) are decisive. EN 15804 + A2 prescribes the “Accumulated Exceedance” method for the “Eutrophobic Potential – Land”. This method quantifies the area on which the carrying capacity of the ecosystems is exceeded and the extent of the exceedance.
Three important emissions that can contribute to acidification are given in the table below.
| Emissions that can contribute to Eutrophication |
Chemical formula | Conversion factor | Unit | Important sources |
| Phosphate | PO43- | 1 | kg PO43- eq/ kg | Use of fertilizers and detergents containing phosphates Wastewater from households, the food industry, the fruit and vegetable industry and paper production. |
| Phosphorus | P | 3.06 | kg PO43- eq/ kg | From the industry From agriculture |
| Nitrogen | N | 0.42 | kg PO43- eq/ kg | Use of fertilizers and detergents containing phosphates From industrial wastewater in the food industry From combustion processes in power plants and transport |
POCP – Photochemical oxidation
Photochemical ozone creation potential
Photochemical oxidation is a form of air pollution that can occur in the lower air layers when organic substances (NMVOC: Non methane volatile organic compounds) and nitrogen oxides in the atmosphere react chemically with each other due to solar radiation. This is what we often call smog.
The air’s content of oxidizing substances, or oxidants, is often used as a measure of photochemical smog. There are a number of oxidants, but it is common to relate the amounts according to the potential impact of ozone (O 3 ). Potential for photochemical oxidation is expressed by kg C 2 H 4 -eqv in EPD.
ADPE and
ADPF
Consumption of non-biological resources
Abiotic depletion potential for fossil resources, Abiotic depletion potential for non fossil.
The availability of useful resources in the world is limited. Therefore, the consumption of resources is an important indicator of the sustainability of a product or system. Both mineral and energy resources can be measured in an LCA. The effect is known as Abiotic Depletion Potential (ADP).
A distinction is made between minerals and energy resources. In the environmental category for mineral consumption (ADPM), all limited resources are calculated according to how rare Antimony is. The result in this environmental category is stated in antimony equivalents (Sb-eq).
Consumption of fossil energy resources is expressed as ADPE. Included fossil resources in the category are oil, natural gas, coal and peat. ADPE quantifies the total potential direct and indirect consumption of energy resources used both as
energy carrier and as a raw material for the product system. MJ fossil fuels are used as a unit for the indicator. This category does not include the consumption of renewable energy resources.
WDP – Water use – Water deprivation potential (AWARE – Available Water Remaining)
Unit = m3 of the worlds available water remaining deprived.
Additional environmental impacts
PM – Particulate Matter emissions
Unit = Disease incidence
IRP –Ionizing radiation – human health
Unit = kgBq U235 eq
This impact category deals mainly with the eventual impact of low dose ionizing radiation on human health of the nuclear fuel cycle. It does not consider effects due to possible nuclear accidents, occupational exposure nor due to radioactive waste disposal in underground facilities. Potential ionizing radiation from the soil, from radon and from some construction materials is also not measured by this indicator.
Toxicity
ETP-fw – Ecotoxicity – freshwater
Unit = CTUe (Comparative Toxit Unit ecosystems)
HTP-c –Human toxicity – carcinogenic
Unit = CTUh (Comparative Toxit Unit humans)
HTP-nc – Human toxicity – non carcinogenic
Unit = CTUh (Comparative Toxit Unit humans)
Soil Quality
Unit = dimensionless (Pt)
The results of these environmental indicator shall be used with care as the uncertainties on these results are high or as there is limited experienced with the indicator.
Consumption of resources
The resource use table describes the consumption of resources to which the product contributes, based on 10 indicators:
PERE
Use of renewable primary energy excluding renewable primary energy resources used as raw materials.
–
REPM
Use of renewable primary energy resources used as raw materials
–
PERT
Total use of renewable primary energy resources.
Sum of PERE og REPM
PENRE
Non renewable primary energy resources used as energy carrier.
–
PENRM
Non renewable primary energy resources used as materials.
–
PENRT
Total use of non renewable primary energy resources.
Summen av PENRE og PENRM.
SM
Use of secondary materials.
–
RSF
Use of renewable secondary fuels.
–
NRSF
Use of non renewable secondary fuels.
–
FW
Use of net fresh water.
–
Waste
The table for waste describes which fractions of waste occur in the product system, based on 3 indicators.
Waste
The table for waste describes which fractions of waste occur in the product system, based on 3 indicators.
HWD
Hazardous waste disposed.
–
NHWD
Non hazardous waste disposed.
–
RWD
Radioactive waste disposed.
–
Remember that the waste may have arisen in processes in raw material production. Radioactive waste, among other things, is normally linked to the production of electricity because the electricity mix contains some nuclear power.
Outgoing flows
The table for outgoing flows describes useful currents assumes product system, based on five indicators.
CRU
Components for reuse.
–
MFR
Materials for recycling.
–
MER
Materials for energy recovery.
–
EEE
Exported electric energy.
–
EET
Exported energy thermal