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.
