This is the third article in a series looking at why oil trains derail at higher rates than ethanol trains. More ethanol was moved by rail from 2010–2015 than oil, but oil trains derail at a higher rate and with more severe consequences. Part one addressed train length as a factor and part two addressed “sloshing.”
On January 25, 2011, a notice appeared in the Federal Register announcing a change in the rules on allowable weight for a rail tank car transporting hazardous materials. It declared the Federal Railroad Administration's (FRA) approval to increase this weight limit, bumping it up to 286,000 pounds gross rail load (GRL) from the previous limit of 263,000 pounds.
Perhaps it was just a coincidence, but this rule change was well-timed for the Bakken oil-by-rail boom that was taking off at that point. Regardless, it had immediate impacts on the ability of the industry to move oil in long unit trains with cars that were heavier than previously allowed.