By Kim Smiley
On August 17, 2014, two freight trains collided head-on in Arkansas, killing two and injuring two more. The accident resulted in a fire after alcohol spilled from a damaged rail car ignited, prompting evacuation of about 500 people from nearby homes. The trains were carrying toxic chemicals, but none of the cars carrying the toxic chemicals are believed to have been breached during the accident.
The National Transportation Safety Board (NTSB) is currently investigating this accident, but an initial Cause Map, or visual root cause analysis, can still be built to help document and illustrate the information that is known. One of the benefits of a Cause Map is that it can easily be expanded to incorporate information as it becomes available. The first step of the Cause Mapping process is to fill in an Outline with the basic information for an incident. In addition, anything that was different at the time of accident is listed. How the incident impacts the overall goals is also documented on the bottom of the Outline.
Like many incidents, there are a number of goals that were impacted by this train collision. The safety goal is obviously impacted by two fatalities and injuries. The property goal is impacted because of the significant damage to the trains and freight. The labor/time goal is impacted because of the response effort and investigation that are required as a result of the accident. Potential impacts or near misses should also be documented so the potential release of toxic chemicals is considered an impact to the environmental goal.
The second step is to perform the analysis by building the Cause Map. To build the Cause Map, start with one impacted goal and ask “why” questions. Each answer is added to the Cause Map. Each impacted goal should be considered and the cause boxes should all connect at some location on the Cause Map. Starting with the safety goal in this example, the first question would be: why were two people killed? This occurred because there was a train collision. The trains collided because they were traveling toward each other on the same track. No details have been released about how the trains ended up on the same track. The trains’ daily recorders (which provide information about the trains’ speed, braking and throttle) have been found and will be analyzed by investigators. The NTSB has stated that they will be looking into a number of factors such as the train signals and fatigue since the accident occurred late at night.
The final step in the Cause Mapping process is to develop solutions that can be implemented to reduce the risk of a similar problem recurring in the future. Since the investigation is ongoing, talk of solutions is premature at this point. Once more is known about the causes that contributed to this issue, the lessons that are learned can be used to develop solutions.