ANSI ASQ ISO 14043-2000 Environmental management - Life cycle assessment - Life cycle interpretation (T14043E).pdf

1、ANSI/ISO 14043-2000AMERICAN NATIONAL STANDARDEnvironmental management Life cycle assessment Life cycle interpretationAMERICAN SOCIETY FOR QUALITYP.O. BOX 3005MILWAUKEE, WI 53201-3005ANSI/ISO 14043-2000AMERICAN NATIONAL STANDARDEnvironmental managementLife cycle assessment Life cycle interpretationAp

2、proved as an American National Standard by:NSF International (NSF)American Society for Testing Gbe the use of an iterative procedure both within the interpretation phase and with the other phases of an LCA oran LCI study;Gbe the provision of links between LCA and other techniques for environmental m

3、anagement by emphasizing thestrengths and limits of an LCA or an LCI study in relation to its goal and scope definition.4.3 Elements of life cycle interpretationThe life cycle interpretation phase of an LCA or an LCI study comprises three elements as depicted in Figure 1, asfollows:Gbe identificatio

4、n of the significant issues based on the results of the LCI and LCIA phases of LCA;Gbe evaluation which considers completeness, sensitivity and consistency checks;Gbe conclusions, recommendations and reporting.ANSI/ISO 14043-200034.4 RelationshipThe relationship of the interpretation phase to other

5、phases of LCA is shown in Figure 1.The goal and scope definition and interpretation phases of life cycle assessment frame the study, whereas theother phases of LCA (LCI and LCIA) produce information on the product system.5 Identification of significant issues5.1 ObjectiveNOTE See clause A.2 in annex

6、 A for examples.The objective of this element is to structure the results from the LCI or LCIA phases in order to determine thesignificant issues, in accordance with the goal and scope definition and interactively with the evaluation element.The purpose of this interaction is to include the implicat

7、ions of the methods used, assumptions made, etc. in thepreceding phases, such as allocation rules, cut-off decisions, selection of impact categories, category indicatorsand models, etc.5.2 Identification and structuring of informationThere are four types of information required from the findings of

8、the preceding phases of the LCA or the LCI study:a) the findings from the preceding phases (LCI and LCIA), which shall be assembled and structured together withinformation on data quality. These results should be structured in an appropriate manner, e.g. in accordancewith the stages in the life cycl

9、e, the different processes or unit operations in the product system, transportation,energy supply and waste management. This may be in the form of data lists, tables, bar diagrams or otherappropriate representation of the inputs and outputs and/or category indicators results. Therefore, all relevant

10、results available at the time will be gathered and consolidated for further analysis;b) methodological choices, such as allocation rules and product system boundaries from the LCI and categoryindicators and models used in LCIA;c) the value-choices used in the study as found in the goal and scope def

11、inition;d) the role and responsibilities of the different interested parties as found in the goal and scope definition inrelation to the application, and also the results from a concurrent critical review process, if conducted.ANSI/ISO 14043-20004Figure 1 Relationships of the elements within the int

12、erpretation phase with the other phases of LCAANSI/ISO 14043-200055.3 Determining the significant issuesWhen the results from the preceding phases (LCI, LCIA) have been found to meet the demands of the goal andscope of the study, the significance of these results shall then be determined. The result

13、s from both the LCI phaseand/or LCIA phase are used for this purpose. This should be done as an iterative process with the evaluationelement.Significant issues can be:Gbe inventory data categories, such as energy , emissions, waste, etc.;Gbe impact categories, such as resource use, Global Warming Po

14、tential, etc.;Gbe essential contributions from life cycle stages to LCI or LCIA results, such as individual unit processes or groupsof processes like transportation and energy production.Determining significant issues of a product system can be simple or complex. This International Standard does not

15、provide guidance on why an issue may or may not be relevant in a study, or why an issue may or may not besignificant for a product system.A variety of specific approaches, methods and tools are available to identify environmental issues and to determinetheir significance.6 Evaluation6.1 Objectives a

16、nd requirementsNOTE See clause A.3 in annex A for examples.The objectives of the evaluation element are to establish and enhance the confidence in and the reliability of theresults of the LCA or the LCI study, including the significant issues identified in the first element of theinterpretation. The

17、 results should be presented in a manner which gives the commissioner or any other interestedparty a clear and understandable view of the outcome of the study.The evaluation shall be undertaken in accordance with the goal and scope of the study, and should take intoaccount the final intended use of

18、the study results.During the evaluation, the use of the following three techniques shall be considered:a) completeness check (see 6.2);b) sensitivity check (see 6.3);c) consistency check (see 6.4).The results of uncertainty analysis and assessment of data quality should supplement these checks.6.2 C

19、ompleteness check6.2.1 ObjectiveThe objective of the completeness check is to ensure that all relevant information and data needed for theinterpretation are available and complete.ANSI/ISO 14043-200066.2.2 Missing or incomplete informationIf any relevant information is missing or incomplete, the nec

20、essity of such information for satisfying the goal andscope of the LCA or LCI study shall be considered.If this information is considered unnecessary, the reason for this should be recorded, after which it is possible toproceed with the evaluation.If any missing information is considered necessary f

21、or determining the significant issues, the preceding phases(LCI, LCIA) should be revisited, or alternatively the goal and scope definition should be adjusted.This finding and its justification shall be recorded.6.3 Sensitivity check6.3.1 ObjectiveThe objective of the sensitivity check is to assess t

22、he reliability of the final results and conclusions by determiningwhether they are affected by uncertainties in the data, allocation methods or calculation of category indicatorresults, etc.This assessment shall include the results of the sensitivity analysis and uncertainty analysis, if performed i

23、n thepreceding phases (LCI, LCIA), and may indicate the need for further sensitivity analysis.6.3.2 Recommendations for conducting a sensitivity checkThe level of detail required in the sensitivity check depends mainly upon the findings of the inventory analysis and,if conducted, the impact assessme

24、nt.In a sensitivity check, consideration shall be given to:a) the issues predetermined by the goal and scope of the LCA or LCI study;b) the results from all other phases of LCA or LCI study and;c) expert judgements and previous experiences.The output of the above sensitivity check determines the nee

25、d for more extensive and/or precise sensitivityanalysis as well as apparent effects on the study results.The inability of a sensitivity check to find significant differences between different study alternatives does notautomatically lead to the conclusion that such differences do not exist. The diff

26、erences may exist but cannot beidentified or quantified due to uncertainties related to the data and methods used.The lack of any significant differences may be the end result of the study.When an LCA is used to support a comparative assertion that is disclosed to the public, the evaluation elements

27、hall include interpretative statements based on detailed sensitivity analysis.6.4 Consistency check6.4.1 ObjectiveThe objective of the consistency check is to determine whether the assumptions, methods and data are consistentwith the goal and scope.ANSI/ISO 14043-200076.4.2 ChecklistIf relevant to t

28、he LCA or LCI study, or required as part of the goal and scope definition, the following questions shallbe addressed.Gbe Are differences in data quality along a product system life cycle and between different product systemsconsistent with the goal and scope of the study?Gbe Have the regional and/or

29、 temporal differences, if any, been consistently applied?Gbe Have allocation rules and system boundaries been consistently applied to all product systems?Gbe Have the elements of impact assessment been consistently applied?7 Conclusions and recommendations7.1 ObjectiveThe objective of this third ele

30、ment of the life cycle interpretation is to draw conclusions and make recommendationsfor the intended audience of the LCA or LCI study.7.2 ConclusionsDrawing conclusions from a study should be done interactively with the other elements in the life cycleinterpretation phase. A logical sequence for th

31、e process is as follows:a) identify the significant issues;b) evaluate the methodology and results for completeness, sensitivity and consistency;c) draw preliminary conclusions and check that these are consistent with the requirements of the goal and scopeof the study, including, in particular, data

32、 quality requirements, predefined assumptions and values, andapplication-oriented requirements;d) if the conclusions are consistent, report as full conclusions. Otherwise return to previous steps a), b) or c) asappropriate.7.3 RecommendationsWhenever appropriate to the goal and scope of the study, s

33、pecific recommendations to decision-makers should bejustified.Recommendations shall be based on the final conclusions of the study, and shall reflect a logical and reasonableconsequence of the conclusions.Recommendations should relate to the intended application as mentioned in ISO 14040.8 Reporting

34、The report shall give a complete and unbiased account of the study, as detailed in ISO 14040. In reporting theinterpretation phase, full transparency in terms of value-choices, rationales and expert judgements made shall bestrictly observed.ANSI/ISO 14043-200089 Other investigations9.1 Critical revi

35、ewThe decision on the type of critical review shall be recorded.NOTE The types of critical review are presented in 7.3 of ISO 14040:1997.Where the study is used to support a comparative assertion that is disclosed to the public, a critical review shall beconducted as presented in 7.3.3 of ISO 14040:

36、1997.ANSI/ISO 14043-20009Annex A(informative)Examples of Life Cycle InterpretationA.1 GeneralThis informative annex is intended to provide constructed examples of the elements within the interpretation phaseof an LCA or an LCI study, in order to help users understand how Life Cycle Interpretation ca

37、n be processed.A.2 Examples for the identification of significant issuesThe identification element (see clause 5) is performed in iteration with the evaluation element (see clause 6). Itconsists of the identification and structuring of information and the subsequent determination of any significanti

38、ssues. The structuring of the available data and information is an iterative process undertaken in conjunction withthe LCI and, if performed, LCIA phases, as well as with the goal and scope definition. This structuring ofinformation may have been completed previously in either the LCI or LCIA, and i

39、s intended to provide an overviewof the results of these earlier phases. This facilitates the determination of important and environmentally relevantissues, as well as the drawing of conclusions and recommendations. On the basis of this structuring process, anysubsequent determination is performed u

40、sing analytical techniques.Depending on the goal and scope of the study, different structuring approaches can be useful. Amongst others, thefollowing possible structuring approaches can be recommended for use:Gbe differentiation of individual life cycle stages; e.g. production of materials, manufact

41、uring of the studied product,use, recycling and waste treatment (see Table A.1);Gbe differentiation between groups of processes, e.g. transportation, energy supply (see Table A.4);Gbe differentiation between processes under different degrees of management influence, e.g. own processes,where changes

42、and improvements can be controlled, and processes which are determined by externalresponsibility, such as national energy policy, supplier specific boundary conditions etc. (see Table A.5);Gbe differentiation between the individual unit processes. This is the highest resolution possible.The output o

43、f this structuring process may be presented as a two-dimensional matrix in which, for example, theabove-mentioned differentiation criteria form the columns and the inventory inputs and outputs or individualcategory indicators results form the rows. It may also be possible to undertake this structuri

44、ng procedure forindividual impact categories for a more detailed examination.The determination of significant issues is based on structured information.Data on the relevance of individual inventory data categories can be predetermined in the goal and scopedefinition, or be available from the invento

45、ry analysis or from other sources, such as the environmentalmanagement system or the environmental policy of the company. Several possible methods exist. Depending onthe goal and scope of the study and the level of detail required, the following methods can be recommended foruse:Gbe contribution ana

46、lysis, in which the contribution of life cycle stages (see Tables A.2 and A.8) or groups ofprocesses (see Table A.4) to the total result are examined, by, for example, expressing the contribution as apercent of the total;ANSI/ISO 14043-200010Gbe dominance analysis, in which, by means of statistical

47、tools or other techniques such as quantitative orqualitative ranking (e.g. ABC Analysis), remarkable or significant contributions are examined (see Table A.3);Gbe influence analysis, in which the possibility of influencing the environmental issues is examined (see Table A.5);Gbe anomaly assessment,

48、in which, based on previous experience, unusual or surprising deviations from expectedor normal results are observed. This allows a later check and guides improvement assessments (seeTable A.6).The result of this determination process may also be presented as a matrix, in which the above-mentioneddi

49、fferentiation criteria form the columns, and the inventory inputs and outputs or the category indicator results formthe rows.It is also possible to undertake this procedure for any specific inventory inputs and outputs selected from the goaland scope definition, or for any single impact category, as a possibility for a more detailed examination. Within thisprocess of identification no data is changed or recalculated. The only modification made is the conversion intopercentages, etc.In the following tables, examples are given as to how a structuring process can be performed. The proposeds