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371.

Goal and Scope

Type III Environmental declarations (Environmental product declarations, EPD) are intended to inform interested parties about the environmental performance characteristics of products. They are based mainly on LCA according to ISO 14040ff, provide its results as inventory or impact category indicators and thus describe the product system under investigation. ISO 14025 is out for ballot as FDIS. The concept of EPD has found a market in particular in the construction sector. It has a considerable part in the European Integrated Product Policy, e.g. documentation of improvement in design for environment, documentation of compliance with green procurement requirements.

Main Features

EPD are a means to communicate the results of a LCA-study according to ISO 14040ff in a comparable and harmonised way. ISO (FDIS) 14025 describes how to develop and document consistent and comparable data sets. This report exemplifies three levels in the development of EPD for which the standard provides requirements. 1. Framework for the development of an EPD program including verification procedures for EPD. 2. Defining the rules for conducting the LCA according to ISO 14040ff as well as additional information for defined product categories (product category rules). 3. Development and documentation of EPD according to the PCR.

Results and Conclusions

After quite a few years of standardisation work the new standard ISO (FDIS) 14025 will provide a systematic approach to documenting and communicating LCA results in an EPD. This will support propagating LCA from its academic origin to a practical tool for the assessment of the environmental performance of a product system. An essential part will be the participation of LCA experts in EPD programs.

Recommendations and Outlook

An enormous effort for developing appropriate conventions will have to be taken by all interested parties to come up with consistent and comparable EPD in different branches. In some areas defining such conventions has been shown to be possible. An important part is the development of quality criteria for modelling as well as for the databases used to calculate the LCA. To find sufficient credibility at economically acceptable conditions with a minimum of bureaucratic effort more practical experience will have to be gained. This holds especially for the trust in the EPD results based on the independence of the review, transparency of procedures and the participation of interested parties. There is a demand on education for SME developing EPD for their products as well as for the users of EPD on how to document EPD transparently and apply them properly.  相似文献   
372.
The central objectives of the European Forum on Integrated Environmental Assessment (EFIEA) include improving the scientific quality of Integrated Environmental Assessments (IEA) as well as strengthening the interactions between science and policy making in environmental matters. This paper is intended to provide a concise assessment of the evolution of IEA methods and present it as a background to current thinking on and practice in IEA. Historical roots of IEA concepts and applications are explored. Common elements and distinctive features in recent proposals to define IEA are sorted and a liberal definition is proposed for the purposes of the present methodological study. This definition emphasizes the interdisciplinary character and environmental policy orientation of IEAs. Changes in the nature, social perception, and management of environmental problems are identified as the major factors driving methodological development in IEAs. A simple scheme is proposed to arrange the main elements of IEA: disciplinary tools, integration tools, and assessment frameworks. The role of IEAs in environmental management is examined by adopting the concept of risk management functions. Due to the varying needs for interdisciplinary research and diverging degrees of policy involvement across those functions, the potential contribution of IEAs to activities belonging to different functions also varies. The flexibility and diversity of IEAs are demonstrated by a sampler of frameworks that have been developed to address profoundly different problems and audiences. This revised version was published online in July 2006 with corrections to the Cover Date. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
373.
Fly ash and sewage sludge are suggested materials for constructing sealing layers covering mine tailings impoundments. Little is known, however, of their effect on vegetation or resistance to root penetration. We investigate: (i) the ability of different plant species to grow in sealing layers comprising fly ash and sewage sludge, (ii) the impact on plant growth of freshly hardened fly ash compared to aged and leached ash, and (iii) the plant stress response to fly ashes of different properties. A 6-mo greenhouse study using birch (Betula pendula Roth.), Scots pine (Pinus sylvestris L.), Kentucky bluegrass (Poa pratensis L.), and willow (Salix viminalis L.) demonstrated that no roots could grow into a compacted layer consisting only of ash, while a 6:4, ash-sludge mixture admitted roots into the upper part and a 1:9, ash-sludge mixture was totally penetrated (to 15 cm in depth) by roots of willow and Scots pine. Freshly hardened ash prevented root growth more effectively than aged ash did, as was observed in tests using reed canarygrass (Phalaris arundinacea L.) and pea (Pisum sativum L.). Furthermore, extracts of highly alkaline ash were more toxic to pea in a 48-h toxicity test than less alkaline ash was. However, stress responses to diluted ash extracts of lower pH, measured as enzyme capacities in dwarf bean (Phaseolus vulgaris L.), were more related to the metal and ion contents. Root penetration of sealing layers is most effectively prevented if little sewage sludge is added, and if ash of high alkalinity is chosen.  相似文献   
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