This article is about the environment impacts of products. Designers use this process to help critique their analysis of inventory systems pdf. Interpreting the results to help make a more informed decision. The goal of LCA is to compare the full range of environmental effects assignable to products and services by quantifying all inputs and outputs of material flows and assessing how these material flows affect the environment.
This information is used to improve processes, support policy and provide a sound basis for informed decisions. There are two main types of LCA. Social LCA should be considered as an approach that is complementary to environmental LCA. ISO 14044 replaced earlier versions of ISO 14041 to ISO 14043. Life Cycle Assessment is carried out in four distinct phases as illustrated in the figure shown to the right. The phases are often interdependent in that the results of one phase will inform how other phases are completed.
An LCA starts with an explicit statement of the goal and scope of the study, which sets out the context of the study and explains how and to whom the results are to be communicated. This is a key step and the ISO standards require that the goal and scope of an LCA be clearly defined and consistent with the intended application. Further, the functional unit is an important basis that enables alternative goods, or services, to be compared and analyzed. The functional flow would be the items necessary for that function, so this would be a brush, tin of paint and the paint itself. Inventory flows include inputs of water, energy, and raw materials, and releases to air, land, and water. To develop the inventory, a flow model of the technical system is constructed using data on inputs and outputs. The flow model is typically illustrated with a flow chart that includes the activities that are going to be assessed in the relevant supply chain and gives a clear picture of the technical system boundaries.
The data must be related to the functional unit defined in the goal and scope definition. Data can be presented in tables and some interpretations can be made already at this stage. The results of the inventory is an LCI which provides information about all inputs and outputs in the form of elementary flow to and from the environment from all the unit processes involved in the study. Inventory flows can number in the hundreds depending on the system boundary. At an industry level, care has to be taken to ensure that questionnaires are completed by a representative sample of producers, leaning toward neither the best nor the worst, and fully representing any regional differences due to energy use, material sourcing or other factors. One area where data access is likely to be difficult is flows from the technosphere. The technosphere is more simply defined as the man-made world.