Since the train derailment in Palestine, OH, on February 3, many have heard the statistic…
More than 99.98% of rail hazmat shipments reach their destination without a release caused by a train accident.
Source: https://www.aar.org/wp-content/uploads/2020/10/AAR-Hazmat-Fact-Sheet.pdf
That statistic may very well be accurate; however, without understanding the definitions used, there could be some padding in the calculation. But let’s assume the 99.98% is 100% accurate, it tells ONLY HALF the story. Risks have to take into account BOTH the frequency and the severity of events to be an accurate reflection of the real risks. The 99.98% stats are the pure frequency with no discussion of the seveirty of consequences of the 0.02% of shipments.
So looking at the 0.02% of accidents, what is the SEVERITY of those rare accidents?