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81.
Kerwin Strauss Alan Brent Sibbele Hietkamp 《The International Journal of Life Cycle Assessment》2006,11(3):162-171
Goal and Background Current Life Cycle Impact Assessment (LCIA) procedures have demonstrated certain limitations in the South African manufacturing
industry. The aim of this paper is to propose new characterisation and normalisation factors for classified mined abiotic
resource depletion categories in the South African context. These factors should reflect the importance of mined resources
as they relate to region-specific resource depletion. The method can also be applied to determine global factors.
Methods The reserve base (as in 2001) of the most commonly produced minerals in South Africa is used as basis to determine characterisation
factors for a non-renewable mineral resources category. The average production of these minerals from 1991 to 2000 is compared
to economically Demonstrated and Demonstrated Marginal Reserves (and not ultimate reserves) to obtain the characterisation
factors in equivalence units, with platinum as the reference mineral. Similarly, for a non-renewable energy resources category,
coal is used in South Africa as equivalent unit as it is the most important fossil fuel for the country. Crude oil and natural
gas resources are currently obtained from reserves elsewhere in the world and characterisation factors are therefore determined
using global resources and production levels. The normalisation factors are based on the total economic reserves of key South
African minerals and world non-renewable energy resources respectively. A case study of the manufacturing of an exhaust system
for a standard sedan is used to compare LCIA results for mined abiotic resource categories that are based on current LCIA
factors and the new South African factors.
Results and Discussion The South African LCIA procedure differs from current methods in that it shows the importance of other mined resources, i.e.
iron ore and crude oil, relative to PGMs and coal for the manufacturing life cycle of the exhaust system. With respect to
PGMs, the current characterisation factors are based on the concentrations of the metals in the ores and the ultimate reserves,
which are erroneous with respect to the actual availability of the mineral resources and the depletion burden placed on these
minerals is consequently too high.
Conclusions The South African LCIA procedure for mined abiotic resources depletion shows the significance of choosing a method, which
is inline with the current situation in the mining industry and its limitations.
Recommendations and Outlook It is proposed to similarly investigate the impacts of the use of other natural resource groups. Water, specifically, must
receive attention in the characterisation phase of LCIAs in South African LCAs. 相似文献
82.
Jane C. Bare Patrick Hofstetter David W. Pennington Helias A. Udo de Haes 《The International Journal of Life Cycle Assessment》2000,5(6):319-326
On May 25–26, 2000 in Brighton (England), the third in a series of international workshops was held under the umbrella of
UNEP addressing issues in Life Cycle Impact Assessment (LCIA). The workshop provided a forum for experts to discuss midpoint
vs. endpoint modeling. Midpoints are considered to be links in the cause-effect chain (environmental mechanism) of an impact
category, prior to the endpoints, at which characterization factors or indicators can be derived to reflect the relative importance
of emissions or extractions. Common examples of midpoint characterization factors include ozone depletion potentials, global
warming potentials, and photochemical ozone (smog) creation potentials. Recently, however, some methodologies have adopted
characterization factors at an endpoint level in the cause-effect chain for all categories of impact (e.g., human health impacts
in terms of disability adjusted life years for carcinogenicity, climate change, ozone depletion, photochemical ozone creation;
or impacts in terms of changes in biodiversity, etc.). The topics addressed at this workshop included the implications of
midpoint versus endpoint indicators with respect to uncertainty (parameter, model and scenario), transparency and the ability
to subsequently resolve trade-offs across impact categories using weighting techniques. The workshop closed with a consensus
that both midpoint and endpoint methodologies provide useful information to the decision maker, prompting the call for tools
that include both in a consistent framework. 相似文献
83.
Louise Dreyer Michael Hauschild Jens Schierbeck 《The International Journal of Life Cycle Assessment》2006,11(2):88-97
Goal, Scope and Background To enhance the use of life cycle assessment (LCA) as a tool in business decision-making, a methodology for Social life cycle
impact assessment (LCIA) is being developed. Social LCA aims at facilitating companies to conduct business in a socially responsible
manner by providing information about the potential social impacts on people caused by the activities in the life cycle of
their product. The development of the methodology has been guided by a business perspective accepting that companies, on the
one hand, have responsibility for the people affected by their business activities, but, on the other hand, must also be able
to compete and make profit in order to survive in the marketplace.
Methods A combined, bottom-up and top-down approach has been taken in the development of the Social LCIA. Universal consensus documents
regarding social issues as well as consideration for the specific business context of companies has guided the determination
of damage categories, impact categories and category indicators.
Results Discussion, and Conclusion. The main results are the following: (1) Impacts on people are naturally related to the conduct
of the companies engaged in the life cycle rather than to the individual industrial processes, as is the case in Environmental
LCA. Inventory analysis is therefore focused on the conduct of the companies engaged in the life cycle. A consequence of this
view is that a key must be determined for relating the social profiles of the companies along the life cycle to the product.
This need is not present in Environmental LCA, where we base the connection on the physical link which exists between process
and product. (2) Boundaries of the product system are determined with respect to the influence that the product manufacturer
exerts over the activities in the product chain. (3) A two-layer Social LCA method with an optional and an obligatory set
of impact categories is suggested to ensure both societal and company relevance of the method. The obligatory set of impact
categories encompasses the minimum expectations to a company conducting responsible business. (4) A new area of protection,
Human dignity and Well-being, is defined and used to guide the modelling of impact chains. (5) The Universal Declaration of
Human Rights serves as normative basis for Social LCA, together with local or country norms based on socio-economic development
goals of individual countries. The International Labour Organisation's Conventions and Recommendations, and the Tripartite
Declaration of Principles concerning Multinational Enterprises and Social Policy, support development of the impact pathway
top-down, starting from the normative basis. (6) The obligatory part of Social LCA addresses the main stakeholder groups,
employees, local community and society.
Recommendations and Outlook Social LCA is still in its infancy and a number of further research tasks within this new area are identified. 相似文献