It is natural that, in the past, engineers gave first consideration to the functional
and economic aspects of new devices. After all, unless devices can be made to
function usefully, they are of no further engineering interest. Furthermore, if a new
device cannot be produced for a cost that is affordable by contemporary society, it
is a waste of engineering time to pursue it further. But the engineers who have
gone before us have succeeded in developing a multitude of products that do function
usefully, and that can be produced economically. Partly because of this,
increasing engineering effort is now being devoted to broader considerations
relating to the influence of engineered products on people and on the environment.
Personnel safety is a consideration that engineers have always kept in mind but
now demands increasing emphasis. In comparison with such relatively straightforward
computations as stress and deflection, determination of safety is likely to be an elusive
and indefinite matter, complicated by psychological and sociological factors. But this
should only add to the appeal of the task for an engineer. It challenges him or her to
assemble all pertinent facts, and then to make good decisions reflecting understanding,
imagination, ingenuity, and judgment.
The important first step in developing engineering competence in the safety area
is cultivating an awareness of its importance. Product safety is of great concern to legislators,
attorneys, judges, jurors, insurance executives, and so forth. But none of these
individuals can contribute directly to the safety of a product; they can only underscore
the urgency of giving appropriate emphasis to safety in the engineering development
of a product. It is the engineer who must carry out the development of safe products.
Safety is inherently a relative matter, and value judgments must be made
regarding trade-offs between safety, cost, weight, and so on. Some years ago the
first author was associated with a particularly safety-conscious company and was in
the position of frequently admonishing the staff safety engineer to reduce further
the inevitable hazards associated with the company’s equipment. When pushed a
little too far one day, this engineer responded, “Look, I have made this model foolproof,
but I can never make it damn foolproof! If someone tries hard enough, he can
hurt himself with this machine!” The next day this gentleman inadvertently proved
his point when he accidentally dropped the new model prototype on his foot and
broke a toe! But the point to be made here is that when society makes decisions relative
to safety requirements, engineers should contribute important input.