After these kinds of incidents, people inevitably and understandably reach for answers. How did it happen? And how can we prevent something like this happening again? But after researching train accidents over the past 25 years, I've discovered that there are rarely, if ever, simple answers for this complex phenomena.
Take one of the most commonly discussed explanations for train accidents: "human error." While this may sound straightforward -- an accident caused by a mistake by a train operator such as a driver or engineer -- there are often a multitude of factors that led to that "error" taking place.
Of course, actions (or inactions) of front-line operators -- who are at the sharp end of the system and can be considered the last layer of defense -- can either save the day or cause a system failure through their own mistakes. And human performance factors such as fatigue or the way they process information can impair situational awareness and alertness and therefore play an important role in determining the outcome.
But train operators' behavior is conditioned by decisions made by work planners or managers, which might have resulted in poor workplace designs, an unbalanced workload, overly complicated operational processes, unsafe conditions, faulty maintenance, ineffective training, nonresponsive managerial systems or poor planning. As such, it is a gross oversimplification to attribute accidents to the actions of frontline operators.
And even if the "correct" systems are in place, a good safety culture goes beyond specific rules and rote adherence to standard operating procedures.
Indeed, the reality is that creating an effective safety culture means instilling attitudes and practices in individuals and organizations that ensure safety concerns are proactively addressed and treated as a high priority.
An organization fostering a strong safety culture will encourage employees to cultivate a questioning attitude, a prudent approach to all aspects of their jobs and create open communication between line workers and management.
These points were underscored by the Deborah Hersman, the former chair of the National Transportation Safety Board, who noted in a bold speech
on recent major U.S. rail accidents that her agency had investigated that: "When we dug deeper, we found that the transit authority wasn't minding the store. In our probable cause, we cited the lack of a safety culture -- from the top down. ... You can fix track and alarms, but building a culture of trust and respect doesn't happen overnight. It takes time. Management must be committed and employees must be willing."
Of course, after any major rail accident in the United States there is also a focus on infrastructure, and usually a renewed call for speeding up the installation of the Positive Train Control systems
. Indeed, PTC has been on the NTSB's most wanted list
for decades -- its investigative reports suggest that even since 2004, more than two dozen train accidents, claiming a total of 65 lives and injuring more than 1,000 people, "could have been prevented or mitigated by PTC
What exactly is PTC? The term refers to a range of technologies that overlay existing safety systems to prevent train-to-train collisions, train derailments because of excessive speed and also improve worker safety. It has already been much talked about in relation to this week's derailment.
However, introduction of PTC cannot assure safety. For a start, designers of the system might not take account of all and every unexpected behaviors that could contribute to an accident. But even successful installation of the required software could have an unintended impact on engineers' situational awareness. It is also worth pointing out that the PTC system is designed to prevent a specific group of accidents, and that overreliance on the technology could potentially impair the overall safety of the system.
But before we can even get to the point of worrying about the impact of PTC, the rail industry is facing a major challenge in actually getting the system in place across the network.
Efforts to implement PTC mean introducing a new technology to an already existing system, a task that is extremely complicated. This may seem surprising -- one might think with such an established mode of transport that systems would be in place for upgrades. But the railroad industry, as with all others, must continually reestablish itself with new technologies. The installation of new technology always involves some changes to the organization and its components, meaning organizational and technological changes must be considered simultaneously.
So, what should we take from all this, and what does it mean moving forward?
The incidents this year are a wake-up call and should lead to a paradigm shift in the U.S. railroad industry, including a systemic study of the three key factors that impact efforts to keep rail transport safe: human, organization and technology.
In addition, the rail industry should take a lead from the kind of multipronged approach to human and systems integration and workplace efficiency that industries such as aviation are taking seriously, including continuous monitoring of leading safety indicators.
Despite the carnage we have seen on our screens, this week's derailment could have been much worse, especially in terms of loss of life. But it is worth keeping in mind the words of the late Nobel physicist Richard Feynman, who when commenting on the safety culture behind the system failure that led to destruction of the Space Shuttle Challenger, said "when playing Russian roulette the fact that the first shot got off safely is little comfort for the next."