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The study of a product's environmental impacts from 'cradle to grave' is formally known as Life Cycle Assessment. It is used to compare products, such as in the choice between plastic or paper cups.

Life Cycle Assessment (ISO 14001) is a 4-stage procedure for the analysis and assessment of products and services along the entire life cycle.

A four-stage procedure for the analysis and assessment of a product or service along its entire life cycle. These stages are:

1. Definition of the Goal and Scope

2. LCI: Life Cycle Inventory

3. LCIA: Life Cycle Impact Assessment

4. Interpretation

The LCA can help in improving the environmental performance of a product or system by:

  • — identifying opportunities at various points in the life cycle of products or processes.
  • — providing quantified information for decision-makers in industry, government and non-government organizations. This information can inform the processes of strategic planning, including how priorities can be set, and the design of products or processes.
  • — provide a basis for selecting relevant indicators of environmental performance, with associated measurement and monitoring techniques.
  • — provide a basis for fair and informative marketing, such as support for claims for ecolabelling and environmental product declarations.
LCA helps compare alternative products

The LCA is a recommended technique of the European Commission, and therefore is present in EU policies regarding environmental impact assessment. Examples are Ecolabel Regulation, Green Product Procurement, Ecodesign Directive, Resource Efficiency initiatives, and as the reference methodology for product and organisation assessment.

1. Goal and Scope

Goal and Scope Definition is the first stage of a project, e.g. LCA.

This phase involves screening of projects, to ensure the LCA is necessary and beneficial to the parties. Projects cannot be open-ended, so goals must be defined. These can have significant consequences for the type of data that is collected, and how it is interpreted and weighted. The scope is an agreed limit to the physical and temporal boundaries of the system(s) being studied.

An LCA study must state clearly what the overall purpose is, what decisions may be made on its findings, and whether the results are for public or internal consumption.

Scoping identifies the function, system, system boundaries, functional unit, data requirements, alternatives for products or services, key assumptions, anticipated limitations, geographical and time limits.

A functional unit is defined, so that unlike products and services may be compared across the board.

The system boundaries are defined in a fair way, so that the project does not grow beyond the resources provided. It may be acceptable to create groups of types of supply industries and disposal mechanisms.

2. Life Cycle Inventory LCI

Also Inventory Analysis, the Life Cycle Inventory (LCI) is the second stage of an LCA, Life Cycle Assessment, in accordance with ISO 14044.

The LCI provides quantified information concerning the product life cycle, including resource use (inputs and outputs), use (functional unit), and the related emissions, but without any attempt at evaluation at this stage.

Environmental Science
LCA Life Cycle Assessment analyses the environmental impacts of products from the cradle to the grave

Which environmental impacts exist in the production, use and disposal of the product? The inventory makes quantitative statements concerning the major stages of the entire life cycle path, concerning the consumption of raw materials and energy, and emissions of pollution. There are a large number of software systems and databanks to aid in this task.

The Inventory involves the collection of data about all inputs and outputs of a system, and requires decisions concerning allocation. In the inventory procedure, there are a number of software processes, which contain algorithms for the calculation of cumulated inventory results, as well as reference databanks.

3. Impact Assessment

Evaluation of the significance of potential environmental impacts, on the basis of the LCI. The impact categories, indicators and characterization models are selected. In the classification stage, the inventory parameters are assigned to impact categories. Then impact measurement quantifies the LCI flow categories into equivalence units, and these can then be summed to obtain an overall impact category total.

4. Interpretation

The final stage of a project, such as an LCA Life Cycle Assessment. It lists and discusses the results in terms of the most important parameters (consistency, completeness and sensitivity analysis), along with conclusions and recommendations.

Now that the goals have been defined, an inventory of material and energy flows, and their impacts, calculated and allocated to environmental impact categories, an assessment is possible. The primary parameters for the results are identified, and the uncertainties quantified. The indicators, such as the Swiss eco-points (EP) system, can be used for a comparison of the different products or processes.

Recommendations concerning the set goals can be derived, to achieve the targets of the maintenance of air quality, ground and water protection, or global warming potential reduction.

Information on the SimaPro software

Information on the Gabi software

Grey energy

The energy necessary for the production, transport, storage, sale and disposal of a product. For example, an imported good has an energy price tag which is higher than a locally-produced identical product. An LCA needs to take into account the grey energy in its determination of environmental footprints in the life cycle of a product.

Global Warming Potential GWP

A measure of the potential of a substance, product or process to cause changes to the atmospheric gases, which will lead to global warming. Often synonymous with emissions of CO2, although other gases, such as methane, are also significant.