Transformations in Safety Thinking

by Dr. Geoff McIntyre

The following are excerpts from an address to medical students at Mahidol University in Bangkok, Thailand, November 2005.

After attending a system safety training class, I asked myself: Are today's colleges, universities, training institutions and government regulatory agencies adequately preparing engineers, technicians and safety inspectors in the concept of "safety"? I don't think so. Also, one of my earliest observations was to question the appropriateness of reading material for a system safety seminar. I decided to address that situation. My book, Patterns in Safety Thinking: A Literature Guide to Air Transportation Safety, addresses the evolutionary spiral of transportation safety thinking beyond the mere absence of accidents. What, then, is "safety?"

My book defines "safety" as "the goal of transforming the levels of risk that inheres in all human activity." Using Hegel's dialectical method of thesis, antithesis and synthesis, I classified the safety literature into separate schools of thought: tort law, reliability engineering and system safety engineering. My literature search revealed that the science of "safety" is truly omni-disciplinary. The behavioral, physical, information and mathematical sciences, as well as governance, play key roles. For example, with regard to the information sciences, in 1975, the aviation sector began data collection, analysis and reporting of incidents through the voluntary, non-punitive Aviation Safety Reporting System. However, in the health professions, it was only in the 2000-2001 timeframe that the U.K. and the U.S. took steps to reduce medical and drug-administration errors and fatalities. That's welcome news when you consider that in the U.S., it is estimated that medical errors account for more than 45,000 - 100,000 fatalities annually. The U.K. Health Secretary estimated 850,000 adverse events annually. Clearly, hospital or health-care provider and drug-administration services should be safely designed to heal, and not to accidentally injure or kill!

The 19^th century iconic figure Lorenzo Coffin, who advocated government intervention in the application of railroad safety engineering design out of regard for human life, was a model for 20^th century automobile safety. Modern-day organizational theorists, sociologists and cognitive scientists — including Barry Turner, Charles Perrow and James Reason — have transformed safety thinking and notions about the imposition of risk and its acceptability in the economic marketplace.

In aviation research and development, whenever we asked ourselves, "How do we know that the system is safe?" the answer was always, "It is safe because reliably built aircraft and redundant air-traffic management operational capabilities have contributed to a low accident rate." While an accident-free system is most desirable, it is important to emphasize that since risk is about the future, it is a fallacy to assume continuity based on past performance. The intellectual giant of the system safety discipline, Willie Hammer, believed that it is a misconception to assume that by eliminating failures, a product will be safe. I share the skepticism of the National Research Council on the subject of reliability numbers: "Like any estimate, a reliability number has both an expected value (mean) and an estimated variance. The variance is often ill defined and hard to estimate. When it is left unstated, it is tempting to read the offered reliability figure (.999) as a firm promise rather than the midpoint of a range." I, for one, do not believe that "safety" can be reduced to a number. And if anyone were to tell me that a system has been built to 10^-23 reliability, I would be extremely skeptical! Why? If for no other reason, because astronomers tell us that our Milky Way Galaxy will collapse and destroy itself at 10^-14, give or take a few million years!

In conclusion, I would like to emphasize that safety thinking requires certain core competencies and qualities of mind. Among them are unquestioned integrity, a questioning mindset (and by that, I mean the respectful questioning of decisions made by those in authority), imagination, persuasiveness, knowledgeability and, above all, humility.

The author is Director of Government and Inter-Society Services for the System Safety Society, and Advisor for System Safety, Flight Standards for the Federal Aviation Administration. The views expressed are entirely those of the author, and do not necessarily represent the views of either the Federal Aviation Administration or the System Safety Society.