What is included in a LCA?
In the following a description of the drawing of an LCA will be made according to the ISO standards. ISO 14040 is an international standard for making LCAs in order to improve transparency. First the four phases in a LCA will be described exemplified by pork as a case and secondly the making of an LCA will be described in further detail. In the word explanation box an explanation of some of the terms used is given.
Important terms for LCA
Functional unit: The amount, weight and quality of the specific product investigated. E.g. 1 kg meat.
System boundaries: Boundaries for which processes in the products life cycle that is included in the LCA.
A process is a smaller part of the product chain, for example the production of fertilizers, milk cartons or fodder and farming. In a process something is produces or treated.
Input materials used in a process, e.g. electricity, fertilizers or soybean meal.
Output is a product from the process, e.g. milk or meat.
Emissions are the discharges from the process. A discharge can be waste, nutrients, gasses that are discharged to water, soil or air.
Environmental impact categories: Different environmental impacts, like global warming, and nutrient enrichment.
Classification: Review of the inventory deciding to which impacts categories the emissions contribute, e.g. global warming.
Characterization: Within each environmental impact category the emissions are calculated to the same unit and summarized.
Equivalent: Several emissions get in the characterization the same unit. For example 1 g N2O contributes as much to the global warming as 310 g CO2 and therefore the 1 g N2O is equal to 310g CO2-equivalents.
Environmental impact: An impact on the environment, e.g. global warming and acidification.
The process of making an LCA can be divided into four phases according to ISO 14001:
- Phase 1: Definition of purpose, goal, functional unit and system boundaries.
- Phase 2: Inventory analysis, including data collection for all processes (in- and output data) and allocation or system expansion between product and co-product.
- Phase 3: Evaluation of the environmental effects, including calculation of the LCA results through classification and characterization.
- Phase 4: Interpretation of the result and identification of significant issues.