By John Kemp Trains carrying oil or ethanol have derailed and caught fire at more than a dozen locations across the United States and Canada in the last five years. Train fires have prompted a fierce debate about the risks of moving large volumes of highly flammable liquids across the rail network and who should be responsible for improving safety. Safety experts agree catastrophic accidents are almost always the result of multiple failures which defeat attempts to prevent them by a defence-in-depth approach that relies on multiple separate safety systems. James Reason, one of the most influential voices on safety issues, chronicled how multiple failures contributed to serious accidents such as Chernobyl and air crashes (“Managing the risks of organizational accidents” 1997). In a modern accident investigation, safety investigators will normally identify an immediate cause such as a broken rail or the failure to set brakes properly. But individual failures should not result in a serious accident if the multiple layers of protection all operate as they are meant to work. So investigations focus on why all the safety systems were defeated at the same time, and what it reveals about hidden flaws and risks in the systems. In the case of train fires, U.S. and Canadian accident investigators have identified human error and broken rails as the main immediate causes of derailments and collisions. Once accidents occurred, however, they were made worse by the tank cars’ failure to contain their hazardous loads. Leaking tank cars created highly dangerous large pool fires. Design flaws proved to be a hidden safety risk. And oil proved to be much more flammable than industry or regulators believed. Under hazmat regulations, crude has been treated as a low-risk hazard when it has behaved more like a medium or high risk one. SHARED RESPONSIBILITY Given the multiple factors which contribute to train fires, railroads, shippers and oil producers must share responsibility for reducing the risk of a catastrophic accident in a densely populated urban area. Railroads must do more to avoid collisions and derailments. Shippers must provide stronger tank cars that contain their loads if a crash happens. And oil shippers must stabilize their crude to ensure it is safe to transport and properly label it under hazardous materials regulations. “Rail safety is a shared responsibility between the shippers and (major) railroads” the association of American Fuel and Petrochemical Manufacturers (AFPM) acknowledged in a letter to the U.S. Department of Transportation. “Our industry is committed to a culture of continuous improvement and making zero incidents the goal,” the association pledged (“AFPM asks DOT to clarify its position on derailments” Mar 17). But there are still bitter arguments about how much different groups should be expected to contribute to improving safety. Following train fires, accident reports and safety regulators have focused on the dangers posed by unstabilised crude and old tank car designs. Attention is now turning to the question of how to cut the number of crashes. Shippers and the oil industry complain the government is not doing enough to force railroads to do a better job of keeping trains on the tracks. TOO MANY DERAILMENTS In its letter to the U.S. Department of Transportation, the AFPM complained “there were over 1,100 ... derailments in 2014, averaging more than three each day; the number one cause being the result of poor track conditions. We cannot believe that (the DOT) believe that these results are acceptable.” “Any effort to enhance rail safety must begin with addressing track integrity and human factors, which account for 60 percent of derailments,” the association insisted. “While more robust tank cars will go a long way towards addressing mitigation in the event of a derailment, keeping the trains on the tracks is the only way to ensure that crude and all other rail shipments will be transported in the safest possible manner.” The letter ended with a pointed question: “Does DOT believe that the current frequency of derailments is acceptable?” IMPROVING SAFETY RECORD US railroads have cut the number of collisions and derailments by 90 percent over the last 40 years, according to incident records compiled by the Federal Railroad Administration (FRA). In 1975, when the volume of rail traffic was roughly the same as today, there were more than 200 collisions between trains and 3,600 derailments on U.S. railroads. These figures are for trains on mainlines and exclude accidents which occurred in switchyards, sidings and on private lines. If all these other places are included, there were a staggering 8,000 accidents in 1975, including 1,000 collisions and 6,000 derailments. By 2014, the number of mainline collisions had been cut to 28 and derailments were reduced to just 329, according to the FRA’s Office of Safety Analysis. The number of serious accidents involving hazardous materials has also fallen. In the late 1970s, there were more than 100 accidents per year which resulted in the release of hazardous materials. Since 2008, the number has fallen to around 20 a year. The number of railcars releasing hazmat has dropped from an annual average of 170 in the late 1970s to just 50 between 2010 and 2014. Reuters has prepared a chartbook showing trends in U.S. rail accidents which can be downloaded here: http://link.reuters.com/wyw34w. AFPM is correct that track failures are the leading cause of derailments. According to the FRA, track failures were the primary cause of almost half of the derailments on U.S. railroads between 2009 and 2014, ahead of equipment failures (26 percent) and human error (15 percent). HIDDEN DANGERS REVEALED Railroads can, correctly, point to an impressive record in improving safety. The problem is that transporting crude by rail has proved to be much more dangerous than industry experts and safety regulators originally estimated. The oil is more flammable than first thought. The tank cars are more prone to rupturing in the event of a derailment. And oil is increasingly moved in unit or block trains consisting of up to 100 tank cars, which present a more concentrated fire risk. Before 2009, the amount of oil moved by rail was minimal, ensuring the risks remained largely hidden. It is hard to assess the true risks of incidents which happen very infrequently when the sample size is small. But as the amount of oil moved by rail has increased by more than 100-fold, risks that were previously latent or hidden have become much more obvious. Given the increased volume of flammable liquids being moved by rail, the U.S. Department of Transportation forecasts there will be an average of 10 derailments involving crude and ethanol trains per year over the next 20 years - of which one incident per year could be a serious accident in an urban area. It is not that U.S. railroads have become less safe in recent years, but that they are now carrying more hazardous cargo than before, and risks that were previously hidden have now become much more obvious. Reducing those risks must now become an urgent priority. Reducing the danger requires a comprehensive strategy that tackles all aspects of the problem (stabilisation, tank cars and track problems), as AFPM noted in its letter. North Dakota has already introduced regulations requiring that all crude must be stabilised prior to shipping and the U.S. and Canadian governments are in the process of finalising tougher standards for new tank cars. But tank cars built to older standards will remain in service for up to a decade. With so many potentially dangerous tank cars likely to remain in service, taking other steps to reduce the risks of derailments is essential. “If older tank cars ... are not phased out sooner, then regulators and industry need to take more steps to reduce the risk of derailments,” Canada’s accident investigators wrote on Tuesday.