On the evening of April 17, 2013, fire broke out at the West Fertilizer Company plant in West, Texas — a small town of some 2,800 people, where the fertilizer store stood a few hundred feet from homes, an apartment block, a nursing home and two schools. Volunteer firefighters were already attacking the blaze inside the seed and fertilizer building when, at 7:51 p.m., about twenty minutes after the fire was first reported, the building’s store of fertilizer-grade ammonium nitrate detonated.
Roughly thirty tons of ammonium nitrate, kept in wooden bins in a combustible wooden building with no sprinkler system, exploded. The blast killed 15 people — twelve of them emergency responders, most of them volunteer firefighters who had never been trained that such a fire could turn into a detonation — and injured more than 260. The plant was destroyed, and more than 150 buildings in the town were damaged or destroyed, among them the nursing home, the apartment block and the schools.
The U.S. Chemical Safety Board, in its final report of January 2016, found that the disaster grew out of a patchwork of weak oversight. Fertilizer-grade ammonium nitrate fell between the federal rules: it was outside the Environmental Protection Agency’s risk management programme and not clearly covered by OSHA’s process safety standard, while combustible construction and storage bins, the absence of sprinklers, and the growth of a town around the plant were all permitted. The Board also found that training and reference materials had not adequately warned emergency responders of the chemical’s potential to detonate in a fire.
The CSB could not establish how the fire itself began. In May 2016 the Bureau of Alcohol, Tobacco, Firearms and Explosives announced its conclusion that the fire had been deliberately set — a finding the Chemical Safety Board noted but did not adopt, and one that has never led to a charge.
The Board recommended that the EPA bring fertilizer-grade ammonium nitrate under its risk management rules and that OSHA close the gaps in its own standards, and it counted some 1,300 facilities across the United States storing the chemical, forty of them in Texas, nearly half within half a mile of a school, nursing home or hospital. Texas afterwards tightened its rules for the storage of ammonium nitrate and strengthened state fire marshal inspection of fertilizer plants.
Download the CSB Final Investigation Report (9 MB file)