In recent weeks we saw Lebanon's government resign in response to the explosion in Beirut on August 4th killing more than 200 people. This explosion was caused by an Ammonium Nitrate fire which according to IChemE are notorious and seem to occur every 20-30 years causing major loss of life and widespread damage. Investigations into the explosion are on-going and lessons learned will no doubt be used to improve safety practices around the world. Fines will be handed out, inspections will be increased, regulations will be enacted and guidelines will be created to prevent this kind of accident from reoccurring. This is the usual process by which safety improves. However, when it comes to risks that happen infrequently this process is not as effective as it could or needs to be. In Malcolm Sparrow's book, "The Character of Harms" he outlines several qualities of these kinds of risks that impact on the effectiveness of risk mitigation specifically with respect to prevention:
The very small number of observed events does not provide a sound basis for probability estimation, nor for detecting any reduction in probabilities resulting from control interventions.
The short-term nature of budget cycles and political terms-of-office, coupled with human tendency to discount future impacts, exacerbates the temptations to do nothing or dot do very little or to d procrastinate on deciding what to do.
The very small number of observed instances of the harm (in many cases zero) provide insufficient basis for any meaningful kind of pattern recognition and identification of concentrations.
All of the preventive work has to be defined, divided up, handed out, conducted, and measured early in the chronological unfolding of the harm, in the realm of precursors to risk, and precursors of the precursors. This is intellectually and challenging work.
Reactive responses and contingency plans are not operated often enough to remain practiced and primed for action.
In the absence of periodic stimuli, vigilance wanes over time.
Reactive responsibilities are curiously decoupled from preventive operations, and engage quite different agencies or institutions.
Investments in reactive capacities (e.g. public health and emergency response) are more readily appreciated, versatile, having a many other potential and easy-to-imagine applications.
Policy makers at the national level find reactive investments easier to make, as their own intellectual and analytic role is reduced to broadcast dissemination of funds for decentralized investment in emergency services. Investment in enhancing preventive control tend, by contrast, to be highly centralized and much more complex technically.
These qualities are even more prevalent when it comes to dealing with natural disasters as opposed to man-made ones. Effective prevention of harm requires addressing the issues arising from these qualities through deliberate attention and a change in mindset. Sparrow outlines a path forward:
Counteract the temptation to ignore the risk. Focus more on the impact of the risk rather than only the likelihoods. Even when deciding not to do something make that a conscious decision not omission.
Define higher-volume, precursor conditions as opportunities for monitoring and goal-setting. Capturing near misses which would be more frequent has been used to support meaningful analysis. When this is reduced to zero then the scope can be broadened bringing in more data to help improve safety further.
Construct formal, disciplined, warning systems understanding that the absence of alarms month over month will create the condition for them to be ignored when they do occur. Countermeasures will need to be established to maintain a state of readiness. Sending alarms to multiple sites so that one crew misinterpreting them does not impede the necessary response.
I highly recommend Sparrow's book, "The Character of Harms" for both regulators and operators looking to improve safety and security outcomes.