Page 217 - Design for Environment A Guide to Sustainable Product Development

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nonhazardous, and nontoxic, thus minimizing concerns about risks
to workers’ health and potential environmental liabilities.

The Challenges of Decision Making
The ultimate purpose of environmental performance assessment is
to support decisions, whether business decisions by manufacturers
or policy decisions by governmental and other organizations. It is
important that such decisions be informed by a generic, life-cycle
framework that recognizes the multitude of impacts that may affect
stakeholders (see Chapter 10). Decisions based on considerations that
are too narrow (e.g., considering only initial costs, or focusing only on
recyclability) are bound to be flawed. On the other hand, decisions
that attempt to factor in an overly broad range of outcomes (e.g., plan-
etary health, societal welfare) are likely to become bogged down in
uncertainty and confusion. A judicious middle point between these
extremes is desirable.
One useful means of pruning the complexity of a decision problem
is to identify first-order impacts that really matter to the decision-mak-
ing organization and that are significantly influenced by the decision
outcome. There are a number of key questions that need to be asked:

• What is the minimal set of environmental metrics that are ade-
quate to represent the design’s environmental performance?
• For each metric, can the degree of environmental improve-
ment associated with each design option be assessed in quan-
titative terms?
• Do side effects of performance improvement need to be
explicitly considered; for example, might an emission reduc-
tion be offset by an increase in risk associated with the substi-
tute technology (e.g., waste incineration)?
• Can the analysis focus on the immediate impacts of the
design change only, or do system-wide risks associated with
materials and energy requirements need to be taken into
account?
• Is it necessary and feasible, either implicitly or explicitly, to
assign relative importance ratings or monetary equivalents to
non-commensurate types of impacts?
• Is there a unifying conceptual model that defines the activi-
ties for which both cost and environmental performance esti-
mates are developed? If not, are the underlying models for
cost and environmental assessment compatible?
• How is uncertainty in cost or environmental assessments rep-
resented and managed? Does the range of uncertainty cast
doubt upon the validity of the decision process?