West's Unsatisfying Legacy

When some half-million pounds of ammonium nitrate fertilizer exploded in the small Texas town of West on Apr. 17, 2013, it not only killed fifteen first responders and other people, injured 160, and damaged or destroyed dozens of buildings.  It showed what can happen when critical information about explosive-material storage is not shared with local authorities.  The West fire department did not know what they were dealing with, and if they had, many or all of the fatalities could have been averted.

Largely as a result of this accident, in the last days of the Obama administration the U. S. Environmental Protection Agency (EPA) issued what became known as its "Chemical Disaster Rule."  According to a recent report in the Texas Tribune, this rule required that companies storing large quantities of potentially explosive chemicals make the fact known to local first responders and the public, and called for companies to make specific emergency plans and conduct meetings on a regular basis about emergency planning.

The rule was delayed until President Trump took office, and now the EPA is saying it's going to roll back many of its provisions.  After the rule was proposed, affected industries complained about it loudly, and so the modified rule eliminates the requirement for public access to information on dangerous chemical inventories.  Corporations claimed, with some justification, that making their inventory quantities public is an invasion of privacy, and could lead to increased threats by terrorist groups wanting to target locations where large quantities of explosive materials are kept.

One reason that news reports mentioned for the rollback was the finding of the accident's cause by the U. S. Bureau of Alcohol, Tobacco, and Firearms (ATF), which was made public to a limited extent in May of 2016.  The ATF concluded that the accident was caused by arson, but the way they concluded that is curious, to say the least. 

According to a 2017 Houston Chronicle article, the agency reportedly spent about $2 million on the investigation and interviewed hundreds of witnesses .  In this way, the ATF says it systematically eliminated any natural and accidental fire scenarios.  Having eliminated all natural and accidental causes, the agency's conclusion was that the fire was deliberately set by a person or persons unknown.  However, there is not a smidgen of direct evidence that indicates the fire was actually arson.

In science, there is an adage that goes, "Absence of evidence is not evidence of absence."  Logically speaking, the ATF is justified in concluding that arson was the cause if and only if they have actually eliminated absolutely every other conceivable possible cause of the fire.  For example, I suspect they did not consider any possible supernatural causes, as those are outside the purview of modern science.  However, since a supernatural cause is still a cause, it counts in the list of other causes they should have considered and actively eliminated, and they didn't.

Apparently, this sort of thing is so common in arson investigations it has a nice Latin legal name:  "negative corpus."  Meaning, I suppose, the body wasn't there, so you can draw some conclusions from its absence.  The Chronicle article says that negative corpus findings are no longer recommended by standards published by the National Fire Protection Association (NFPA) adopted in 2011.  But local and even federal arson investigators still use it.

The convenient thing about the conclusion that arson was at fault is that it absolves the facility operator from a large burden of responsibility.  It's one thing if your own faulty practices cause an accident, but legally it's quite a different thing if somebody sneaks in and sets your place on fire deliberately. 

To be fair, I would not have the slightest clue of how to investigate an explosion so violent that it left a large crater where the plant used to be and scattered it over a good part of a square mile.  It's quite possible that some tiny critical piece of evidence—a frayed extension cord, for example—would be entirely obliterated in the blast, making a successful investigation of the cause impossible.  But I would also not want to spend two million dollars on an investigation and end up saying, "We dunno." 

The West explosion revealed serious deficiencies in how ammonium nitrate and other explosive materials are stored and how such information is shared, or not shared.  Although I do not have direct access to the revised EPA rule, I can only hope by reading between the lines of the summaries that it still has some provision for informing local first responders about the presence of dangerous chemicals.  That was the most harmful missing factor in what led up to the tragedy at West. 

And as the NFPA now recommends, investigators should be able to say, "Look, we tried, but there's just no way to figure out what caused this," instead of defaulting to a spurious conclusion of arson simply because it's legally convenient and lets companies off the hook.  While arson is also one of the logical possibilities, it shouldn't be shoved to the front of the line simply because it alleviates liability problems.

The town of West was forever changed by the explosion in 2013, and I expressed the hope at the time that something good would come of the tragedy in the form of tightened regulation of facilities that were potential bombs, such as the West Fertilizer Company plant.  It's entirely possible that the original EPA regulations were excessively burdensome to companies that are already doing more or less what they should do because their private insurers keep them in line.  But I hope the newly revised regulations still make sure that the local first responders, whose lives will be on the line if anything goes wrong, at least have the information they need to take suitable precautions for their own safety and the safety of others.

Sources:   I referred to articles in the Texas Tribune at https://www.texastribune.org/2019/11/21/west-texas-fertilizer-explosion-spurred-safety-rules-trump-rescinding/ and https://www.texastribune.org/2016/05/11/west-fertilizer-plant-explosion-was-intentional-of/, and in the Houston Chronicle at https://www.houstonchronicle.com/news/houston-texas/houston/article/Experts-cast-doubt-on-ATF-s-arson-finding-in-West-11725989.php, as well as the Wikipedia article on the West Fertilizer Company explosion.

ATF Says West Explosion Deliberately Set

In an announcement last Wednesday, Robert Elder, Special Agent in Charge of the Houston Field Division of the Bureau of Alcohol, Tobacco, Firearms, and Explosives, announced his agency's finding that the explosion of Apr. 17, 2013 of a fertilizer storage facility in West, Texas was a "criminal act."  The agency has offered a $50,000 reward to anyone having information that leads to the arrest and conviction of those responsible.  No other details of the investigation's findings were released, but ATF says it has done over 400 interviews leading up to their determination that somebody deliberately set the fire that led to the explosion.

This bit of news raises more questions than it answers, not all of them technical ones.  But we can ask some technical ones for starters.

The explosion itself was so violent that it showed up on seismometers hundreds of miles away, left a crater over 90 feet (27 meters) wide, and scattered debris and other evidence for miles around, besides killing 15 people and injuring about 160.  How anybody could find enough evidence to conclude it was a deliberate act of arson is a good question.  But the ATF people are apparently well experienced and equipped to do that.  Unless and until their evidence comes out in a criminal trial, it's not possible to comment on the quality or quantity of their research and investigations.  But their findings are consistent with the conclusions of the U. S. Chemical Safety Hazard and Investigation Board, which released its final report on the explosion in January of this year.  In it, the Board stated that one possible cause of the fire was that it was intentionally set, although there were other possibilities as well.

If the West explosion turns out to be deliberately set, that does not reduce the need for fertilizer plants to store ammonium nitrate more safely.  (Ammonium nitrate was the fertilizer material that detonated at West and caused so much damage.)  A representative of the Texas Ag Industries Association made the news in April of 2015 by saying that until a definite cause for the explosion could be identified, there was no need to issue new regulations for the storage of ammonium nitrate.  One hopes that now the ATF has apparently determined a definite cause, the Texas Ag Industries Association will reconsider its stance, even if it is nothing more than increasing security around existing fertilizer plants.

To those who lost loved ones or were injured or lost property in the explosion, the news that the fire was intentional can only cause more grief.  We can only speculate about the motives of the perpetrator, although an ATF spokesman has ruled out terrorism as a motive.  If the arsonist knew that the ammonium nitrate stored at the plant was likely to explode, the culpability in the case is compounded, but in any case, I hope that if the culprit is still around to be found, that justice can be served.  I say that in the unlikely event that the person who set the fire was also a first responder who was killed in the explosion.

Such a situation is not unheard of, as the case of John Leonard Orr shows.  Orr was a fire captain and arson investigator in Glendale, California in the 1980s.  Following a series of suspicious fires, in 1991 a fingerprint recovered from one of the fires was found to match Orr's, and he was tried and convicted on three counts of arson.  Partly because two children died in one of the fires Orr allegedly set, he was sentenced to life in prison without the possibility of parole.

I also hope that the ATF's body of evidence will withstand scrutiny in a court of law.  With a special Maryland fire-investigation lab, the ATF is probably the cream of the fire-investigator crop in the U. S.  But not all fire investigations are equal, and there have been cases where people have been convicted of arson with evidence that was later shown to be shoddy and insubstantial, as a 2009 New Yorker article by David Grann called "Trial By Fire" described.  In that case, a man named Todd Willingham was convicted of arson in a Corsicana, Texas fire that claimed the lives of his three children.  After he was executed the arson evidence was re-examined by experts, one of whom said that the original investigation was more "characteristic of mystics or psychics" than of modern scientific methods. 

After all the time and effort spent on the West investigation, we can be fairly sure that the ATF would not conclude that the explosion resulted from a deliberate act unless they have strong and convincing evidence.  I'm sure the residents of West are eager to hear the details of the ATF's findings, which I hope will be released in due time.  But I'm sorry that after all the suffering those folks have had to go through, they now have to deal with the real possibility that someone, somewhere intended for the West explosion to happen.

Sources:  This news was reported in various sources, and in particular a Houston Chronicle article by  Mark Collette at http://www.chron.com/news/houston-texas/houston/article/ATF-says-West-explosion-was-a-criminal-act-7462148.php to which I referred.  A video of the news conference at which Robert Elder announced the ATF's findings was posted by the Dallas Morning News at https://www.youtube.com/watch?v=mJWa3tDEYL4.  The ATF's announcement of a reward in connection with the explosion can be found at https://www.atf.gov/news/pr/atf-announces-50000-reward-west-texas-fatality-fire.  I referred to the U. S. Chemical Safety Hazard and Investigation Board's final report on the explosion at http://www.csb.gov/assets/1/19/West_Fertilizer_FINAL_Report_for_website_0223161.pdf.  I also referred to the New Yorker website version of the article "Trial by Fire" at http://www.newyorker.com/magazine/2009/09/07/trial-by-fire and the Wikipedia articles on the West Fertilizer Company explosion and John Leonard Orr. 

West One Year Later: Will It Happen Again?

On April 22, the U. S. Chemical Safety Board held a news conference to present its recommendations about how to prevent another disaster such as the one in West, Texas that killed fifteen, injured over 200, and caused millions of dollars of property damage on April 17, 2013.  So far, not a lot has changed in terms of federal or state regulations pertaining to ammonium nitrate, the fertilizer chemical that exploded on that fateful day.  But a fertilizer trade organization has issued a set of recommendations that, if followed, will go some distance toward reducing the chances that another disastrous accident involving the chemical will happen again.

As long ago as 2002, the Chemical Safety Board recommended that ammonium nitrate be included in OSHA (Occupational Safety and Health Administration) and EPA (Environmental Protection Administration) regulatory programs, but these agencies have not yet chosen to act on these recommendations.  Ammonium nitrate falls in a gray area between chemicals such as nitroglycerin or TNT that are clearly dangerous, and others such as sand that are harmless.  Under most circumstances, ammonium nitrate can be handled with little or no risk.  But under certain combinations of heat, pressure, and/or shock, the chemical detonates, transforming many tons of solid matter into hot gases that expand explosively, as they did in West. 

In response to the West accident a trade organization called The Fertilizer Institute issued a fourteen-page booklet to its members last February with the title "Safety and Security Guidelines for the Storage and Transportation of Fertilizer Grade Ammonium Nitrate at Fertilizer Retail Facilities."  The title does not promise exciting reading, though the legalese and lengthy definitions of different types of ammonium-nitrate fertilizer are enlivened by color photos of fertilizer manufacturing and handling installations.  The pamphlet summarizes most of the precautions which, if followed, would have gone a long way toward preventing the West disaster. 

These measures fall into two categories: (1) ways to prevent ammonium nitrate from exploding in the first place, and (2) ways to avert death and destruction if a fire breaks out where ammonium nitrate is stored, and the stuff explodes anyway.  The prevention measures are more or less what you'd expect:  things like storing the material in non-combustible bins, rather than wooden ones as were used in the West firm; installing sprinkler systems or other fire-prevention and fire-fighting facilities; and treating places where ammonium nitrate is stored like flammable-material storage areas (no-smoking signs, no sparks or flames nearby, etc.).  Because an exact cause of the fire at West that led to the explosion may never be found, we cannot know for certain if these precautions would have prevented the tragedy.  But obviously, they are good things to do, and if fertilizer retailers around the country follow these prevention guidelines, the chances of another such accident will be reduced.

The second category of recommendations is more problematic.  It involves informing the wider community, including first-responder agencies, that ammonium nitrate is stored in the facility and should be treated with extra caution.  By the nature of the business, many fertilizer retailers are located in semi-rural or thinly populated areas.  These locales are often served by volunteer fire departments, and while volunteer firemen theoretically should be trained as well as full-time paid firefighters, the reality is that their training may be on the sketchy side.   The Chemical Safety Board concluded that the first responders in West did not know of the dangers presented by the large quantity of ammonium nitrate stored at the plant where they responded to what appeared at first to be an ordinary fire, and were much too close for safety.  Consequently, when the plant exploded, most of the people who died were firefighters.  The guidance handbook says "The rule of thumb is if outside emergency responders are necessary, do not fight AN [ammonium nitrate] fires.  For fires that have engaged AN, plans should focus on evacuation of the area."  In other words: don't fight, run. 

While the trade-association brochure's advice is good, it has no legal standing, and firms are free to adopt its recommendations or ignore them.  Simply as a matter of asset protection, I would hope that fertilizer retailers who sell ammonium nitrate are at least considering an upgrade of unsafe storage facilities, and the brochure provides good guidelines as to how to carry this out.  However, the informational side of the recommendations may be harder to implement.  A business owner may feel some reluctance in volunteering the information to local authorities that his facility harbors material that might reduce a wide swath of his neighborhood to rubble.  Nevertheless, there may be courageous and conscientious owners who will do such things. 

Both the Chemical Safety Board and various other authorities have called for tighter compulsory regulation of ammonium nitrate storage and transportation.  This is a political as well as a technical and ethical matter, and politics these days tends to go to polarized extremes.  On the one hand are those who favor centralized uniform federal regulations for all sorts of things, including ammonium nitrate.  On the other hand, a prominent plank in the Tea Party platform is the idea that government regulations have gone too far and are stifling free enterprise and economic growth.  The regulations contemplated with regard to ammonium nitrate vary from rules about how the stuff is stored to rules about notification and training of local first responders.  It seems to me that sensible regulations requiring the exchange of information, perhaps implemented by some sort of web-based registry, would be the least costly way to make sure that at a minimum, any firefighters responding to an ammonium-nitrate fire would know what they are dealing with and would take appropriate precautions. 

One way of dealing with this information problem is by the use of fire codes.  However, the state of Texas has a strong history of anti-regulatory bias.  In fact, counties with low population density in Texas are actually prohibited by state law from enacting fire codes at all.  So around July and December, you see roadside fireworks stands popping up for a few weeks with nary a concern for any safety beyond the immediate self-preservation of the owners in case a customer drops a burning cigarette. 

So far, the only concrete public action toward preventing more ammonium-nitrate fertilizer disasters has been the Fertilizer Institute's brochure.  While they deserve credit for their efforts, only time will tell whether enough has changed to keep another fertilizer plant from blowing up, or to save lives if it does.

Sources:  The news conference in Dallas on Apr. 22, 2014 held by the Chemical Safety Board was summarized by a UPI report at http://www.upi.com/Top_News/US/2014/04/22/US-investigators-Better-regulation-could-have-prevented-deadly-fertilizer-explosion/4731398190424/.  The Chemical Safety Board's own statements at the conference can be downloaded at http://www.csb.gov/assets/1/16/Statement_-_News_Conference_(Final).pdf.  The Fertilizer Institute recommendations can be found at http://www.tfi.org/ammonium_nitrate_guidelines.  And I blogged on the West explosion previously on Apr. 22 and May 20, 2013.

OSHA Fine for West Explosion: What's the Point?

Last April 17, when the West Fertilizer Company's facility in the Texas town of the same name exploded, killing 15 and laying waste not only to the plant but to a good chunk of the town as well, it had been more than 25 years since a federal Occupational Safety and Health (OSHA) inspector personally appeared at the plant.  But that did not stop OSHA from issuing a $118,300 fine against the company last week, on October 9, for a list of 24 safety violations.  This news came out despite the federal government's shutdown because Sen. Barbara Boxer's office found out about it and notified news media.  The company has fifteen days to either pay the fine or file an administrative appeal with OSHA, and company representatives said they were conferring with lawyers about their next step.

Depending on how you view the idea of punishment, OSHA's fine either looks pretty silly or seems like a sound and reasonable step for such an agency to take.  Let's examine the case for silly first.

Suppose you run a small fertilizer company that has gone through bankruptcy in the last few years and probably has total assets, land and facilities included, of at most a few million dollars, with a one-million-dollar liability insurance policy on the property.  Due to causes that even combined federal and state investigations cannot precisely determine, your plant blows up, killing fifteen of your fellow citizens, causing over a hundred million dollars' worth of damage to your town, and by the way, completely demolishing the physical assets of your business.  Half a year later, along comes OSHA and lays a fine of over $100,000 on you for various historical violations based on testimony of how the fertilizer that exploded was stored and for not having an emergency response plan.  How do you respond?

I am not running the West Fertilizer Company, but at the moment, hiring lawyers to file an administrative appeal will be a lot cheaper than paying the fine up front, which would probably suck up most of any remaining cash and possibly make the company go out of business altogether.  Not that they haven't had time to do anything more than deal with lawyers and lawsuits since April anyway.  Obviously, the better time for OSHA to have levied such a fine would have been before the April explosion, when the changes possibly stimulated by such a large penalty might have had the positive effect of preventing the explosion. At this point, the fine brings to mind a scene in the animated film Wallace & Gromit:  The Curse of the Were-Rabbit.  At one point, the brilliant but silent canine character Gromit, a skilled driver, goes on a wild car chase that winds up with his vehicle stalled out after a minor collision.  Sitting there silently on a dark road, Gromit seems lost in the depths of despair, thinking that things cannot possibly get worse.  And then they do:  the car's airbag deploys in his face.  OSHA's fine is timed as well as Gromit's airbag.

Whether the fine makes any sense depends on one's theory of punishment.  In How to Think About the Great Ideas, philosopher Mortimer Adler points out that there are two main opposing theories of punishment:  retribution and prevention.  As retribution, OSHA's fine would be laughable, were it not for the somber circumstances.  It is hard to imagine a retributive penalty for the West Fertilizer Company, which after all is a business firm, not an individual.  It has already been reduced to smithereens, and unless you contemplate something primitive like blowing up the houses of the owners in retribution for the explosion of their plant, it is hard to conceive of a punishment that would be purely retributive in character. 

OSHA fines appear to be based on the preventive theory of punishment, as are most administrative fines levied on corporations in general.  While it is clear that it is way too late for this fine to prevent what happened in West, it is by no means too late for other operators of fertilizer manufacturing and storage facilities to take note of the fine and the reasons why it was levied.  There are over a dozen similar fertilizer plants just in Texas alone, and it is a good bet that many of these are lacking in the same safety features that would have prevented or mitigated the accident in West.  One hopes that insurance companies will take the initiative to motivate their fertilizer-plant customers to upgrade their facilities and procedures to make it less likely that something like the West explosion will happen.  And there is always the chance that enlightened managers and owners will take it upon themselves to make the needed changes:  following existing federal guidelines about how ammonium nitrate should be stored, putting emergency procedures in place and even practicing fire drills, and taking other sensible precautions that are not rocket science but often get neglected when an organization skids by for years and avoids the very unlikely but disastrous chance that a normally well-behaved chemical like ammonium nitrate will explode. 

While it's true that the horse named the West fertilizer explosion has long since left the barn, there are many other horses of a similar nature who can be kept in place if fertilizer plants and facilities across the country learn from the sad experience of the Texas town that got famous for a reason nobody wanted.  I hope that OSHA's actions, however tardy, serve as a warning to prevent another tragedy like the one we saw last spring.

Sources:  The OSHA fine was described in a news article in the Waco Tribune that appeared in the online edition of Oct. 11 at http://www.wacotrib.com/news/business/west-fertilizer-co-cited-for-safety-violations/article_6d83a0cc-f28f-5763-ba23-f8229c0dfbae.html.  Mortimer Adler's How to Think About the Great Ideas (Chicago:  Carus Publishing, 2000) describes the great idea of Punishment on pp. 274-283.

What We Don't Know About Chemical Accidents

The fertilizer-plant explosion last April 17 in West, Texas that killed 15 and demolished a good part of the town was only the most recent of a number of accidents involving hazardous chemicals that have happened in Texas over the years.  Home to a large number of refining and petrochemical plants and other high-tech industries, Texas has had more of its share of explosions, fires, releases of toxic and polluting chemicals, and other chemical-related accidents.  But when a team of Dallas Morning News reporters tried to answer what they thought was a simple, straightforward question about the frequency of chemical accidents, they found a mare's nest of conflicting and incomplete statistics.  Is this a basic problem that leads to a higher rate of accidents than we would otherwise have?  Or is it just an inherent difficulty that comes about because of the nature of chemical accidents?

The News reporters were unable to find a single database of national scope that answered the question they were asking.  I think what they wanted to find was something like what the U. S. Center for Disease Control (CDC) maintains on statistics such as cases of measles or rabies, or the National Transportation Safety Board's database on fatal accidents involving air transport.  But what they found instead was a hodgepodge of things:  raw unfiltered lists of emergency calls to the U. S. Coast Guard, lists of incidents investigated by the Occupational Safety and Health Administration (OSHA), and data collected by the Chemical Safety Board, which relies primarily on media reports—in other words, the reporters themselves!  They found glaring inconsistencies among the numbers cited by the various sources of information, and although they were able to identify 24 potentially serious chemical accidents in Texas between 2008 and 2011, they were almost sure that the true number was higher.

The first question in compiling statistics on something is to define exactly what you are compiling statistics on.  The problem of defining a chemical accident is not a trivial one.  Clearly, if I'm working in my garage and accidentally knock over a can of used oil that spills into the ground, that is not something that should be treated with the same seriousness as the West explosion.  But by some definitions, both are chemical accidents.  So first, a line needs to be drawn defining how serious an accident should be before it is logged into a database.  But how do you draw that line?  Should you log only accidents that resulted in casualties (deaths or injury to persons), or a minimum amount of property damage, or all accidents that involve certain types of particularly hazardous chemicals?  There are millions of kinds of chemicals, and the hazard to humans of many of them are simply unknown. 

Even if we agree that casualty-only accidents are what we want, the problems of privacy and legal liability come into play. As noted by the Dallas Morning News reporters, private firms are reluctant to share details of their inner workings that might leave them open to lawsuits or might prove repellent to potential investors.  As the aftermath of the West explosion has shown, the legal environment of chemical accidents is complex, poorly defined, and is the result of a tangle of criminal, regulatory, and civil codes that do not produce the kind of clear-cut situations that are easy to record in databases.

Not mentioned by the investigative reporters is a powerful external force on chemical industries which makes most firms maintain and enforce strict internal safety rules and records of accidents.  This force is applied by insurance companies.  My brother-in-law is the chief safety officer for a large firm that operates refineries in several states.  One of his main jobs is to travel to the home offices of the company's main insurers annually, and present detailed reports of his firm's safety records and the measures they are taking to make sure lessons are learned from near-misses in order to prevent bigger accidents in the future.  While these matters are handled out of the public eye, the desire to keep insured is one reason that the chemical industry as a whole has a safety record that is much better than it could be, considering the millions of pounds of hazardous material that passes through its facilities every year.  And in conversations with my brother-in-law, I have learned that firms quickly learn about accidents at other firms, and take steps to make sure those types of incidents don't happen to them too.  In other words, a good bit of what a comprehensive nationwide database of chemical accident reports would do, is already taking place: namely, information-sharing among the plant operators themselves.

Of course, there are always exceptions, which often tend to be among the smaller independent operators that can't afford full-time safety officers and large staffs.  The West fertilizer plant was one such operation, but it is not clear that having an accurate national database of fertilizer-plant explosions would have made much difference in the way that particular accident transpired. 

More and better publicly accessible information about chemical accidents is a desirable thing, and I hope that the West explosion will lead to a better system of gathering and presenting such data nationwide.  But if this goal is achieved at the cost of burdensome, onerous, and unjustly harsh regulations of industries which already do a fairly good job of self-policing due to the economic interests of their insurers, the price tag may be more than we should pay.

Sources: The Dallas Morning News report appeared on that paper's website on Aug. 24-25 at http://www.dallasnews.com/news/west-explosion/headlines/20130824-after-west-disaster-news-study-finds-u.s.-chemical-safety-data-wrong-about-90-percent.ece.

Update on West: Causes and Consequences

Last Thursday, May 16, officials from the Fire Marshal’s Office of Texas and the federal Bureau of Alcohol, Tobacco, Firearms, and Explosives announced that the cause of the April 17 fertilizer-plant explosion in the town of West was “undetermined.”  However, they had eliminated a number of possible causes and narrowed the probable ones to three:  something to do with the 120-V electrical system in the plant, a golf cart stored in the same room with the ammonium nitrate bins, and arson. 

Considering the horrible jumble of wreckage that the explosion left behind, even this much progress in the investigation is laudable.  The investigators did determine that about 28 to 34 tons of ammonium nitrate, a fertilizer ingredient, exploded in the blast that dug a crater ten feet deep and 93 feet wide and caused seismometers to register the equivalent of a 2.1-magnitude earthquake.  It could have been worse:  another 140 tons of the material stored either onsite or in railcars at a nearby siding did not explode. 

The investigation revealed that the ammonium nitrate that exploded was stored in wooden bins next to bins of flammable seeds.  No sprinkler system was in place, and under current fire-code regulations none was required in the industrial facility. 

The reconstructed sequence of events is fairly brief.  At 7:29 PM on the evening of April 17, a fire was reported at the facility.  Unless there were personnel on site that late in the evening, it is likely that no one was present at the time and the first report was turned in only after smoke was visible outside the plant.  So the fire may have had some time to get going before it was reported.  This is significant, because when ammonium nitrate is heated, it can turn from a white powder into a solid mass that transmits shock waves well.

Nine minutes after the fire was reported, firefighters arrived and began to play water on the blaze, which the investigation stated did not contribute to the explosion.  Investigators speculated that as the fire progressed, a piece of heavy equipment might have come loose and fallen onto the now-solidified mass of ammonium nitrate, causing a detonation wave that led to two almost simultaneous explosions, 22 minutes after the fire was reported.  It was these explosions that killed fifteen people, most of them firefighters, and laid waste to 37 blocks of the small town. 

Not involved in the news conference at which these findings were announced, were members of the federal Chemical Safety Board (CSB), an agency charged with investigating chemical accidents with a view toward making recommendations about how to avoid them in the future.  A Dallas Morning News reporter interviewed members of the Board involved in the West investigation, and their work is still continuing.  Rather than focusing on the narrow question of exact causes, the CSB is examining the broader picture of how regulations affected the outcome of the incident and how community responses could have been improved.  Questions have been raised, for example, about the wisdom of storing so much explosive material literally across the street from an apartment complex, and not much farther from a school and a nursing home.  Any time a fire occurs at a facility where large amounts of ammonium nitrate are stored, prudence would dictate that at a minimum, the area within a possible explosion range should be evacuated. 

On July 30, 2009, a fire at a fertilizer plant in Bryan, Texas where large quantities of ammonium nitrate were stored led to the evacuation of thousands of residents of that college town (home to Texas A&M) as a precaution.  Fortunately, the fire burned itself out without incident and no damage outside the plant resulted.  But as the West explosion shows, things could have turned out very differently.  The Bryan incident also differs from West in that the people who accidentally started the fire were the ones who reported it promptly, giving more warning than otherwise.

While regulation is always a two-edged sword that can cause more harm than it alleviates, the West explosion will at least inspire re-examination of the whole complex of federal, state, and local laws, as well as insurance-company practices, that bear on the storage of ammonium-nitrate fertilizer.  Determining the appropriate level of regulation, as well as the appropriate agency or agencies to issue regulations, is not an easy task.  Local officials, especially in smaller towns such as West, rarely have the expertise to come up with customized, science-based regulations about hazardous materials that do not cause problems most of the time.  But federal regulations are a blunt instrument, and customarily matters such as fire codes are left to the states and local communities to decide on.  National organizations such as the National Fire Protection Association (NFPA) issue model guidelines and codes, but it is a state or local option as to whether these codes are made part of local laws. 

The deaths in the West explosion were preventable, and I for one hope that the memory of this tragedy will lodge in the minds of firefighters, code-enforcement officials, and governmental agencies who are in a position to keep such things from happening, or at least lower the chances of them happening, in the future.  The sharing of basic information and knowledge about how much of what stuff is stored where needs to be mandated so that first responders know both what they are dealing with and what is prudent to do in a given situation.  Firefighting is a hazardous job, and loss of life in the line of duty is one of the risks that firefighters take on when they join their companies.  But if better information and procedures, even if mandated by the federal government, will keep both firefighters and their communities safer in situations such as what happened in West last month, it may be time to change the way things are done.

Sources:  I referred to an article on the West investigation news conference published on the Dallas Morning News website on May 18 at http://www.dallasnews.com/news/west-explosion/headlines/20130518-in-west-investigators-focus-shifts-from-explosions-cause-to-closing-safety-gaps.ece.  I also used an article from the KRHD-TV website for information on the Bryan, Texas evacuation, found at http://www.abc40.com/story/10823244/ammonium-nitrate-fire-forces-mass-evacuation.