What Would John Snow Do?

By LT COL STEPHEN FREEDMAN, 89 AW Flight Safety Officer

Ask yourself: What would John Snow do? Are you thinking of befriending the Free Folk, riding dragons, and uniting the North? Well, not that Jon Snow, King of the North. I am talking about Dr. John Snow, a 19th-century English doctor who is credited with proving that cholera, a deadly infection that attacks the small intestine, actually spreads through contaminated water and not by “bad air” as was generally believed at the time (germ theory was not yet discovered). He is often described as the father of epidemiology and pioneered the use of what we would now call a “heat map.”

How does an 1854 outbreak of cholera in London and a well pump handle relate to safety in 2019?

Let me try to paint the picture. For a decade prior to the outbreak, the London government started the unprecedented process of publicly releasing all the mortality reports in the city, which included age, gender, where they lived, and cause of death. Although unprecedented, the government hoped that publicly releasing data would help to identify a pattern. Dr. Snow, along with the help of Reverend Henry Whitehead, mapped all the cholera cases in London. Rev. Whitehead interviewed many of the families and victims to get further information beyond what the data showed. Dr. Snow was not a very social person, so the interviews from the socially connected Rev. Whitehead proved invaluable to fill the gaps left in the data. This multi-disciplinary effort of combining social science, interviewing, and data analysis was also a novel approach in the mid-19th-century.

After plotting all the illnesses and deaths on a map, Dr. Snow made two conclusions: first, the rate of mortality was higher near the Broad Street well pump, and, second, between the companies that supplied the water, one had a significantly higher mortality rate than the other. Dr. Snow used this pattern recognition to isolate the outbreak to a water pump on Broad Street, which astonishingly, was associated with a 10 percent mortality of the residents who lived near the water pump.

Dr. Snow’s map assigned a dot for each death, and the cluster was focused around the Broad Street well pump. Based on interviews, Dr. Snow and Rev. Whitehead also found deaths in houses farther away from the Broad Street well were related, because some of the families preferred to drink that well water or the children went to school near the well.

Dr. Snow took his findings to local officials and convinced them to take the handle off the pump, making it impossible to draw water from it. Shortly after removing the well handle, the outbreak came to an end.

Researchers later discovered that the public well from which the pump drew water was dug only a few feet from a cesspit. The cloth diaper of a baby, who had contracted cholera from another source, had been washed into this cesspit and was the point source of the outbreak.

I view safety somewhat like the epidemiological science—one where we must use pattern recognition and data along with a healthy dose of intuition to target our proactive safety efforts. Epidemiology is the cornerstone of public health, shaping policy decisions and evidence-based practices by identifying risk factors for disease and targets for preventive healthcare. That sounds a lot like our Safety Management System (SMS) pillars: “Policy and leadership, risk management, assurance, and promotion and education.”

Like the London Government in 1854 and Snow and Whitehead, we have a wealth of open source data not only from the Department of Defense/U.S. Air Force (DoD/USAF) but also from the Federal Aviation Administration (FAA), the National Aeronautics and Space Administration (NASA), and industry partners. Our efforts must not be isolated to the office and crunching numbers, however; we must be out in the field observing behaviors and talking with Airmen out on the line. This data source is one of the most important aspects of our safety profession—to fly the flag of safety, to be out on the line, and to be available and observant. We must carry out spot inspections 24/7/365, not only the Monday through Friday day shift. All shifts deserve the same level of observation.

What do you think are our biggest threats and hazards? What is your next mishap? How do we prevent it? Let us investigate those areas and begin a targeted, proactive campaign to stop it. Part of the back story on Dr. Snow is that he was theorizing the water-borne transmission of cholera for a few years before the 1854 outbreak. In the end, change only favors minds that are diligently looking and preparing for discovery.

Some of the trends I have seen over the years are maintenance induced failures (MIF) or maintenance (MX) related mishaps. For a long time, the biggest hazard was the airplane and the pilot on the flight deck. Over the years, the low hanging fruit was to put safety devices in airplanes, produce more reliable engines, and to focus on crew resource management. Those efforts have yielded a nearly asymptotically low mishap rate. While the USAF experienced a recent uptick in mishaps in 2018, and civil aviation is mourning the deaths from three recent accidents, 2017 had zero fatalities in Air Mobility Command and the world did not have even one commercial fatal flight. Astonishing!

However, the rate of MIF or MX related mishaps remains steady. I believe that is because we have not placed the same level of proactive safety and human factors in the maintenance career field. Additionally, the concept of Just Culture and confidential reporting is novel to maintenance career fields.

Under-reporting is one of the biggest threats to an effective safety management system. I believe in a multi-pronged attack against threats and hazards. That attack happens with three reporting mechanisms available: AMC Form 97, Airman Safety Action Program (ASAP), and Air Force Technical Order (AFTO) Form 781s, while Line Observation Safety Audit (LOSA) and Military Flight Operations Quality Assurance (MFOQA) are convening in the flanks.

Safety is one of the few careers where we can have a truly lasting positive impact on our operations. I want you to take pride in the fact that the recommendations and improvements we write in our reports will prevent mishaps. Like Dr. Snow, we need to identify the trends, embrace multidisciplinary collaboration, have the fortitude to stand-up for our theories, and find ways to implement the recommendations that are a win-win for the Airmen out on the line.

After all, sometimes a life-saving recommendation can be as simple as removing a pump handle.