Place and Time - Sustainable Design: The Science of Sustainability and Green Engineering - page 170

to reevaluate what it is we teach our engineering students. We believe that all
engineers and architects should include in their educational quiver at least some
arrows that will help them make the difficult yet sustainable decisions faced by all
design professionals.
This means that design professionals are risk reduction agents, if you will.
Environmental challenges force designers to consider the physicochemical char-
acteristics of the pollutants and match these with the biogeochemical character-
istics of the media where these pollutants are found. We have had to increase
our understanding of myriad ways that these characteristics would influence the
time that these chemicals would remain in the environment, their likelihood to
be accumulated in the food chain, and how toxic they would be to humans and
other organisms. Those contaminants that have all three of these characteristics
worry us the most. In fact, such contaminants have come to be known as “PBTs”:
persistent, bioaccumulating toxicants.
The problems at Love Canal, Times Beach, Valley of the Drums, and the many
hazardous waste sites that followed them pushed regulators to approach pollutants
from the perspective of risk. The principal value added by environmental profes-
sionals is the skill to improve the quality of human health and ecosystems. Thus,
the change in risk is one of the best ways to measure the success of green designs.
By extension, reliability lets us know how well we are preventing pollution, re-
ducing exposures to pollutants, protecting ecosystems, and even protecting the
public welfare (e.g., buildings exposed to low-pH precipitation).
Risk, as it is generally understood, is the chance that some unwelcome event
will occur. The operation of an automobile, for example, introduces the driver
and passengers to the risk of a crash that can cause damage, injuries, and even
death. Environmental failures have emphasized the need to somehow quantify
and manage risks. Understanding the factors that lead to a risk is known as risk
analysis. The reduction of this risk (e.g., by wearing seat belts in the driving
example) is risk management. Risk management is often differentiated from risk
assessment , which is comprised of the scientific considerations of a risk. Risk
management includes the policies, laws, and other societal aspects of risk.
Designers must consider the interrelationships among factors that put people
at risk, suggesting that we are risk analysts. As mentioned, green designs must
be based on sound application of the physical sciences. Sound science must be
the foundation of risk assessments. Engineers control things and, as such, are
risk managers. Engineers are held responsible for designing safe products and
processes, and the public holds us accountable for its health, safety, and welfare.
Similarly, architects must provide designs that are sustained in the best interests
of their clients. The public expects designers to “give results, not excuses,” 16
and risk and reliability are accountability measures of their success. Engineers
design systems to reduce risk and look for ways to enhance the reliability of these
systems. Thus, green design deals directly or indirectly with risk and reliability.