Industrial Fire World publisher David White urged federal officials to conduct an in depth scientific study of the fertilizer ingredient ammonium nitrate (AN) to determine the exact conditions that triggered the April 2012 fatal explosion that devastated West, TX.
“I want the government or industry to do some research because I want to know why at West we had one building full of ammonium nitrate explode and kill a bunch of people, yet we had another one catch fire not that far away that did not,” White said.
White spoke briefly at a public meeting held in April 22 in West to release the preliminary findings of the U.S. Chemical Safety Board investigation into the April 17, 2012, fertilizer plant explosion and fire that killed 15, injured 226 and caused widespread damage throughout the town.
The CSB investigation focused on shortcomings in existing regulations, standards and guidance at the federal, state and county level.
CSB investigator Jarad Denton said the location of ammonium nitrate facilities in or near populated areas exists across the country.
“According to data reported to the Department of Homeland Security under the chemical facility anti-terrorism standards, there are 1,350 facilities across the country storing ammonium nitrate in quantities greater than 2,000 pounds,” Denton said.
At West, an estimated 60 tons of AN exploded at the burning West Fertilizer plant, damaging or destroying nearly 500 structures in the community. However, a smaller storage bin containing AN did not detonate despite the blast that destroyed the fertilizer plant. Also, a railroad car containing nearly 100 tons of AN was knocked over by the blast without detonating.
On July 30, 2009, the El Dorado Chemical plant near Bryan, TX, burned to the ground without detonating nearly 550 tons of AN stored there. Likewise, in Athens, TX, a storage facility with at least 70 tons of AN on hand burned in May 2014 with no explosion resulting.
“I want the National Institute of Standards and Technology or somebody to please help us understand why,” White said.
Johnnie A. Banks, lead investigator for the U.S. Chemical Safety Board in its West probe, reported on a history of fatal explosions involving AN. Among the past incident were:
• In 1921, an explosion at a chemical plant in Germany caused 561 deaths with more than 2,000 injured.
• In 1947, a burning cargo ship carrying 2,300 tons of wax coated AN exploded in the port of Texas City, TX. A second burning ship packed with AN exploded 16 hours later. The disaster killed 581 people and injured more than 5,000.
• In 1994, a fertilizer plant explosion in Port Neal, IA, killed 4 people, injured 18 and released nearly 5,700 tons of anhydrous ammonia over a six-day period.
• In 2001, an explosion at a fertilizer factory in Toulouse, France, killed 31 people and injured more than 2,400 others.
Banks said the comparison of the West explosion to the Bryan fire demonstrates the unpredictable nature of ammonium nitrate exposed to burning conditions.
At West, first responders had only 22 minutes to access the situation and attempt to extinguish the fire before the explosion.
“At the El Dorado incident, the Bryan Fire Department didn’t arrive at the facility until 24 minutes after the initial 911 call was made,” Banks said.
The first volunteer responder arrived on scene about 9 minutes after the first 911 call, Banks said. That responder immediately noted that the material involved presented an explosion hazard.
“Due to a lack of water supply, firefighters made the decision to let the facility burn, rather than attempt to fight the fire,” Banks said. “It wasn’t until one hour later that an evacuation was ordered for surrounding facilities.”
Banks said the striking differences in outcome between the West incident and the Bryan incident resonated with investigators.
“Early on in the response to the fire in Bryan the discovery of a Material Safety Data Sheet indicated that firefighters should respond with copious amounts of water,” Banks said. “They didn’t have water, so they pulled back and allowed the facility to burn to the ground. They also affected an evacuation of the surrounding community.”
Useful information obtained from the El Dorado fire was not effectively disseminated to other responders in communities where AN is stored or utilized, Banks said.
In response to a question from CSB chairman Rafael Moure-Eraso, Glenn P. Corbett, an associate professor of fire science at John Jay College of Criminal Justice, said that the handling of ammonium nitrate tends to be a “bi-polar issue.”
“On one hand we think of it as this innocuous fertilizer and, on the other hand, we think of it as an explosive,” Corbett said. “The (fire) code reflects that sort of ambiguity.”
Corbett, as did White, said little research exists on ammonium nitrate in its working “habitat,” such as storage or during handling.
“I found contradictory information about ventilation of a fire,” Corbett said. “In Texas City, the ship was sealed and an explosion occurred. NFPA 400 recommends that we ventilate the fire. But in some cases, that is not what was recommended. We don’t know exactly how these materials detonate.”
Banks, responding to Corbett, said that the behavior of ammonium nitrate in a fire involves a “seeming randomness.”
“We looked at a number of different incidents where there’s been a fire involving ammonium nitrate,” Banks said. “In some instances, virtually the same circumstances exist but with completely different outcomes. In one instance it will explode and in another it doesn’t.”
Any number of factors such as shock or contamination may contribute to detonation, Banks said. The split-second decisions made by the firefighters in West were based on the best information available to them.
“Within 20 minutes they responded from wherever they were in West,” Banks said. “They answered the call, bringing four units to the site. And they began doing what they were tasked with doing, heroically.”
CSB investigators noted that the NFPA recommends that firefighters evacuate from AN fires of “massive and uncontrollable proportions.” Federal Department of Transportation guidance contained in the Emergency Response Guidebook, which is widely used by firefighters, suggests fighting even large ammonium nitrate fertilizer fire by flooding the area with water from a distance.
However, the investigation has found that the response guidance appears to be vague since terms such as “massive,” “uncontrollable,” “large” and “distance” are not clearly defined.
“If you’re getting to a point where it’s massive and uncontrollable, you’re already behind the eight ball,” Corbett said. “Given that most of these facilities are in remote rural areas, time is not on our side.”
At that point, Corbett said his recommendation would be to concentrate on evacuation.
“It is my opinion that it is a mistake for (NFPA 400) to recommend a fire attack in an ammonium nitrate warehouse, such as the one found in West,” Corbett said. “It is the initial wrong course of action. I believe a responding firefighter should concentrate their efforts purely on evacuations, which was done in Bryan, TX, in 2009.”
Pre-planning for fire emergencies at AN facilities would improve awareness, CSB investigator Samuel Oyewole said. However, the federal government has no requirements that fire departments develop site specific pre-incident plans for businesses dealing with hazardous materials such as AN.
The Texas State Fire Marshal’s report states that it does not suggest the firefighters who lost their lives, or any surviving members of the West VFD failed to perform their duties as they had been trained, or as expected, by their organization.
“The analysis does, however, indicate a systemic deficiency in the training and preparation of the West VFD to adequately prepare for the incident they encountered at the West Fertilizer Company fire,” the report states.
The CSB report states that West volunteer firefighters were not aware of the explosion hazard from the AN stored at West Fertilizer and were caught in harm’s way when the blast occurred.
The Rev. John Crowder of the First Baptist Church of West defended the actions of West’s firefighters faced with an unprecedented local emergency.
“While we have all had an entire year to assess the situation, evaluate the needs and prioritize the various options, our firefighters had 20 minutes to get to the scene and do all that,” Crowder said. “Within 20 short minutes our local heroes show up, got organized and did exactly what the expert tonight said they should have done.”
The CSB noted that while U.S. standards for ammonium nitrate have apparently remained static for decades, other countries have more rigorious standards covering both storage and siting of nearby buildings. For example, the United Kingdom’s Health and Safety Executive states in guidance dating to 1996 that “ammonium nitrate should normally be stored in single story, dedicated, well-ventilated buildings that are constructed from materials that will not burn, such as concrete, bricks or steel.”
Also, the UK guidance calls for storage bays “constructed of a material that does not burn, preferably concrete.”
Moure-Eraso said the fertilizer industry in the US has taken recent steps to get fertilizer distributors and others to carefully handle AN.
Specifically, the Fertilizer Institute and the Agricultural Retailers Association created what they call “Responsible Ag,” a third-party auditing program for fertilizer retailers. These associations have distributed a comprehensive document called “Safety and Security Guidelines for the Storage and Transportation of Fertilizer Grade Ammonium Nitrate at Fertilizer Retail Facilities.”
Texas State Fire Marshal Chris Connealy said that Texas has 96 facilities spread over 66 counties handling AN in amounts of 10,000 pounds or greater. Since the West disaster, 18 of those facilities have been re-inspected by the state. At least four of the total 96 facilities have since decided to discontinue working with ammonium nitrate.
Bruce Johnson, director of fire service activities with the International Code Council, noted that only Texas counties with a population greater than 250,000 or adjacent to counties above that population are permitted to pass fire codes under Texas law.
Connealy responded that since the Texas Legislature meets bi-annually there has not been a chance to address the issue of county fire codes.
“I’m very pro-fire codes,” Connealy said. “But as I stated earlier, I think it is better managed at a local level.”
Lynn White, co-owner of IFW, told the meeting that despite zoning ordinances too often land developers looking for cost-effective sites for new development do not consider the risk that makes that land more affordable.
West Mayor Tommy Muska said state law does not give cities the size of West the authority to exercise extra territorial jurisdiction to regulate any activity outside their city limits, such as the operations at West Fertilizer.
“The city of West fire department is only responsible for fire protection in our corporate city limits,” Muska said. “Any response to outside fires is a matter of courtesy. And we respond.”
Likewise, new land use zoning and fire sprinkler requirements would have to be made retroactively effective to provide any relief for West citizens, Muska said.
“It seems to me that it would be more effective and easier to regulate if you mandate a safer product,” Muska said, noting that technology exists to coat AN in such a way as to make it less explosive.