Sustainable Design and Social Responsibility - Sustainable Design: The Science of Sustainability and Green Engineering - page 192

proper operation and maintenance. Thus, a master flowchart can be developed for
all of the decisions and subconsequences that ultimately lead to various outcomes
from which the designer can choose. Event trees or fault trees allow you to look at
possible consequences from each decision. Figure 5.1 provides a simple example.
Designing for the environment (DFE) can be very challenging when there are
competing interests and risk trade-offs. This is common in biomedical engineer-
ing. Consider, for example, asthma medication that has been delivered to the
lungs using a greenhouse gas (GHG) propellant. At first blush the green engi-
neering perspective may forbid it; however, if the total amount of the propellant
used in these devices constitutes only 0.0001% of the total GHG used, perhaps
the contribution to global warming is considered insignificant. The problem, as
illustrated by the Tragedy of the Commons, is that if the cumulative effect of
all of the “insignificant” contributions is ignored, collectively they could cause
irreversible damage. When it comes to public health trade-offs, the significance
is determined by medical efficaciousness. For example, if there are alternatives to
this particular GHG that are not greenhouse gases and that are just as effective
at delivering the medication, they are preferable from a risk management per-
spective. As evidence, some asthma medications are now delivered mechanically.
If there are no effective alternatives, the trade-off with the environmental effects
may be justifiable (see the discussion box “Green Medicine”).
Green Medicine
If you have recently attended a medical school hooding ceremony for grad-
uating medical doctors, you may have noticed that the hood is bright green.
This symbolizes early medicine's use of herbs and other plants to treat ill-
nesses. Thus, modern medicine's origins are truly green. Recently, medi-
cal practice has been rediscovering these roots (pun intended) in a manner
similar to that of other technical disciplines. The professions are embracing
sustainability.
Medicine and engineering are intimately connected. Some engineering
disciplines stand at the interface, particularly biomedical engineering. But
most design professions are increasingly affected by health care and its massive
infrastructure. This infrastructure includes the classic “hard” design chal-
lenges for architects and engineers, such as efficient design of hospitals and
other health care facilities, design of state-of-the-science medical devices, and
retrofitting antiquated facilities and processes. In fact, obsolescence is increasing
exponentially with daily advances in biomedicine, so designers must be agile
and adaptive in their designs. Arguably, medical design is arguably the greatest
challenge for adaptive designs, since small change, can be the difference be-
tween life and death.