Preliminary Findings of the U. S. Chemical Safety Board from its Investigation of the West Fertilizer Explosion and Fire

The CSB has made the following observations and preliminary findings to date, which are subject to further revision and deve lopment as the inve stigation unfolds:

1) The explosion at West Fertilizer resulted fr om an intense fire in a wooden warehouse building that led to the detonation of appr oximately 30 tons of AN stored inside in wooden bins. Not only were the warehouse a nd bins combustible, but the building also contained significant amounts of combustible seeds, which likely contributed to the intensity of the fire. According to availa ble seismic data, the explosion was a very powerful event.

2) Whether additional factors such as material characteristics, shock, or contamination

contributed to the incident remains to be determined. Company employees described a PVC plastic pipe that was lo cated directly above the AN bi n that detonated, and likely would have been melted by the fire. A dditionally, large amou nts of potentially flammable anhydrous ammonia we re stored along the southe rn edge of the warehouse building.

3) The building lacked a sprinkler system or other systems to automatically detect or suppress fire, especially when the building was unoccupied after hours. By the time firefighters were able to reach the site, the fire was intense and out of control. Just 20 minutes after the first notification to the West Volunteer Fire Department, the

detonation occurred.

4) Both National Fire Protection Association (NFPA) and the Intern ational Code Council (ICC), private organizations th at develop fire codes that are widely applied across the U.S., have written code provisions for the sa fety of ammonium nitr ate. Many of these safety provisions are quite old 1 and appear to be confusi ng or contradictory, even to code experts, and are in need of a comprehe nsive review in light of the West disaster and other recent accidents. For example the ICC’s International Fire Code directs users to a defunct code for ammonium nitrate (NFPA 490, last issued in 2002) rather than the current code, known as NFPA 400.

5) The existing fire codes do contain some useful provisions; for example the codes do require a fire resistant barrier between AN and any stored flammable or combustible materials and have provisions to avoid AN confinement and promote ventilation during fire conditions. However, even th e most current NFPA 400 standard allows AN to be stored in wooden buildings and in woode n bins, and does not mandate automatic sprinkler systems unless more than 2500 tons of AN is being stored – vastly more than the approximately 30 tons that was sufficient to devastate much of the town of West. In addition, the standard contains a “grandf athering” provision that allows existing buildings that were constructed prior to c ode adoption – and fail to meet all of its provisions – to continue in use.

1 NFPA 400 refers users to a 1953 publication by the U.S. Bureau of Mines for information on the explosive properties of AN.6) Texas has not adopted a statewide fire code , and state law actually prohibits most smaller rural counties from adopting a fire code. McLennan County, where the West facility was located, had not adopted a fire code, although it technically had the authority to do so because of its proximity to the more populous Bell County. The West Fertilizer facility was thus not required to follow any NFPA or ICC recommendations for the storage of AN.

7) Although some U.S. distributors have constructed fire-resista nt concrete structures for storing AN, fertilizer industry officials have reported to the CSB that wooden buildings

are still the norm for the distributi on of AN fertilizer across the U.S.

8) Industry has developed other forms of ammoni um nitrate that are reported to reduce or

eliminate the risk of accid ental detonation. For exampl e, compounding the ammonium nitrate with calcium carbonate ( limestone) “practica lly eliminates any risk of explosion in its storage, transportation, and handling,” while preserving the AN’s nutritive value. 2

Calcium ammonium nitrate fertilizers have been widely used in Europe. Ammonium

sulfate nitrate also has been found to be non- explosive provided the percentage of AN

is held below about 37%. 3

9) The federal OSHA standard for “Explo sives and Blasting Agents” (29 CFR 1910.109) does have requirements for ammonium nitrate fe rtilizer; its provisions are similar to the

NFPA codes. Unlike the NFPA codes – whic h West was not legally required to follow under any fire code – the OSHA standard w ould have applied. Like NFPA, however, the OSHA standard does not prohibit wooden bins or wooden construction, and does not require sprinklers unless more than 2500 tons of AN is present. However, OSHA public records indicate that OSHA last inspected the faci lity in 1985, and no citations were issued under the “Explosives and Blasting Agents” standard.

10) OSHA’s Process Safety Management standard (29 CFR 1910.119) or PSM was adopted in 1992 and is designed to preven t catastrophic workplace incidents involving highly hazardous chemicals. PSM requires co mpanies to have a variety of management elements to prevent catastrophic incidents, such as conducting hazard analyses and developing emergency plans. Ammonium n itrate is not, however, one of the listed chemicals that triggers PSM coverage. The PSM standard also contains an exemption

for retail facilities.

11) The EPA’s Risk Management Program rule (40 CFR Part 68) or RMP was adopted in 1996 and is designed to prevent catastrophic offsite and environmental damage from extremely hazardous substances. As the name suggests, the rule requires covered facilities to develop a Risk Management Plan, implement various safety programs, and analyze offsite consequences from po tential accidents. Once again, however,

ammonium nitrate is not one of the listed chemicals that triggers RMP coverage. West

Fertilizer was RMP-covered due to its stored ammonia, and the company’s offsite consequence analysis considered only the possibility of an ammonia leak, not an explosion of ammonium nitrate.

2 Calcium ammonium nitrate (CAN) must still be protected from contamination with other chemicals that can resensitize it to detonation. See Popovici Ipochim, N.N.; Icechim, M.M.; “Other Ammoni um Nitrate Fertilizers;” In Keleti, C. (ed.); Nitric Acid and Fertilizer Nitrates ; New York: Marcel Dekker Inc., 1985.

3 Ibid.12) OSHA considered adding ammonium nitrate along with other highl y reactive chemicals

to its list of PSM-covered substances in th e late 1990’s. However, this proposal was shelved in 2001. In developing the RMP re gulation, the EPA did not explicitly include explosives or reactive chemi cals in the list of covered chemicals. In 2002, the CSB issued a study on reactive hazards, identifying 167 prior reactive incidents (including a 1994 explosion at an ammonium nitrate ma nufacturer). The Board recommended that both OSHA and EPA expand their standards to include reactive chemicals and hazards. However, neither agency has yet acted upon the recommendations.

13) No federal, state, or local standards have been identified that restrict the siting of ammonium nitrate storage facili ties in the vicinity of ho mes, schools, businesses, and

health care facilities. In We st, Texas, there were hundreds of such buildings within a mile radius, which were exposed to seri ous or life-threatening hazards when the explosion occurred on April 17.

14) West volunteer firefighters we re not made aware of the e xplosion hazard from the AN stored at West Fertilizer, and were caught in harm’s way when the blast occurred. NFPA recommends that firefighters evacu ate from AN fires of “massive and uncontrollable proportions.” Federal DOT guidance contained in the Emergency Response Guidebook, which is widely used by firefighters, suggests fighting even large

ammonium nitrate fertilizer fires by “flood[ing] the area wi th water from a distance.” However, the response guidance appears to be vague since terms such as “massive,” “uncontrollable,” “large,” and “distance” are not clearly defined. All of these provisions should be reviewed and harmonized in light of the West disaster to ensure that firefighters are adequately protected a nd are not put into da nger protecting property

alone.

15) While U.S. standards for ammonium nitrat e have apparently remained static for decades, other countries have more rigorous standards covering both storage and siting of nearby buildings. For example, the U.K. ’s Health and Safety Executive states in guidance dating to 1996 that “ammonium nitr ate should normally be stored in single storey, dedicated, well-ventilated buildings that are constructed from materials that will not burn, such as concre te, bricks or steel.” 4 The U.K. guidance calls for storage bays

“constructed of a material that doe s not burn, preferably concrete.”

16) CF Industries, a principal manufacturer of AN that was one of the suppliers to West, also recommends more rigorous safeguards in its Material Safety Data Sheet (MSDS)

for the chemical. In the section entitled “Handling and Storage,” CF recommends that “Storage construction should be of non-combustible materials and preferably equipped with an automatic sprinkler system.” 5 Although companies are required to issue MSDS’s, the recipients of this information like West Fertilizer are not obligated to follow the recommended safety precautions. West lacked these safeguards.

17) The Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) has regulations for

ammonium nitrate used as an explosive but these do not apply to ammonium nitrate used as fertilizer. The U.S. Depart ment of Homeland S ecurity has reporting

4 U.K. Health and Safety Exec utive; “Storing and Handling Amm onium Nitrate;” Available from http://www.hse.gov.uk/pubns/indg230.pdf

5 http://www.cfindustries.com/pdf/Am monium-Nitrate-Amtrate-MSDS.pdfrequirements for companies that have a thre shold amount of fertilizer grade ammonium nitrate. However, the authority of DHS is to require security measures to protect against theft, diversion, or ot her intentional acts; DHS does not regulate the safety of ammonium nitrate to prev ent conditions leading to accidental detonation.

18) The Emergency Planning and Community Right-to-Know Act of 1986 (EPCRA) contains an exemption from hazardous chemical reporting for “fertilizer held for sale by a retailer to the ultimate customer.” The EPA has interpreted this provision as not applying to firms, like West, that make cust om blends of bulk fertilizer for customers’ use. In 2012, West Fertilizer filed an EP CRA Tier II report with the McLennan County Local Emergency Planning Committee (LEPC). West reported the presence of up to 270 tons of ammonium nitrate, as well as anhydrous ammonia, at the site. The company did not provide the LEPC or the We st Fire Department with an ammonium nitrate MSDS indicating the material’s h azards, nor does EPCRA automatically require that information to be provided. There is no indication that West’s filing with local

authorities resulted in an effort to plan for an ammonium nitrate emergency.