Ammonium Nitrate (AN) is made from ammonia and nitric acid. It is a heavily regulated chemical compound that has numerous positive uses across multiple industries. In commercial agriculture, for instance, AN is used as a fertilizer for crops. When used by the commercial explosives industry, ammonium nitrate, an oxidizing agent, can have energetic properties when combined with certain chemical compounds. When used to produce commercial explosives, end users include the mining, construction, and quarrying industries.
By itself, AN is a safe and stable compound that under normal storage conditions is extremely unlikely to detonate. The commercial explosives industry is governed by a stringent set of federal regulations and industry best practices to help ensure the safety of the workforce and nearby communities where AN is being stored, transported, or used. When these industry best practices and federal regulations are not followed, such as being accidentally contaminated by other chemicals or placed in proximity to other combustibles, there can be subsequent hazards. But by itself, AN will not burn.
With nearly 100 years of understanding the potential hazards associated with AN, we know that when federal regulations and best practices of the commercial explosives industry are followed, AN is safe to handle, transport and use.
The U.S. commercial explosives industry manufactures, handles, transports, stores, and uses ammonium nitrate in two forms. The first form is a liquid known as ammonium nitrate solution (ANS). The other form is solid and is referred to as technical grade ammonium nitrate (TGAN). TGAN has a bead-like shape called “prill."
Forty-seven percent of the AN manufactured in the United States is used for industrial purposes. Together, TGAN and ANS account for over 90 percent of the raw material feed used to manufacture modern commercial explosives.
Why Ammonium Nitrate?
The reason AN is used across the commercial explosives supply chain in such a high volume is that it's a much more stable compound to use and is a great safety improvement over the nitroglycerine-based products that were used in the past. Another reason AN is used as a main ingredient in commercial explosives is that the elements that make up its composition are both abundant and affordable.
How is Ammonium Nitrate Regulated?
Occupational Safety and Health Administration (OSHA)
OSHA regulates the storage and handling of AN and requires compliance with OSHA's hazard communication standard. OSHA also uses its General Duty Clause authority to address AN storage and handling practices that do not conform to accepted industry safety, such as those published by IME and the National Fire Protection Association (NFPA).
Pipeline and Hazardous Materials Administration (PHMSA);
The U.S. Department of Transportation’s Pipeline and Hazardous Materials Administration (PHMSA) regulates the transportation of AN. This includes making sure that transporters of AN receive the proper training, register with USDOT, and comply with all other USDOT requirements for transporting hazardous materials. Individual drivers who are responsible for the safe transport of AN must have a hazardous materials endorsement (HME) as part of their commercial driver’s license and pass a background check.
Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF)
When ammonium nitrate is mixed with fuel oil (ANFO) or other emulsifiers to take on explosive characteristics, the primary regulator of its storage and distribution then becomes the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). ATF’s role in regulating ANFO includes oversight of storage, the security of storage facilities, record keeping of inventory of commercial explosives, and conducting background checks of employees who manufacture, handle, or use commercial explosives, including ANFO.
U.S. Department of Homeland Security (DHS)
DHS regulates AN as a chemical of interest through the Chemical Facility Anti-Terrorism Standards (CFATS) program which aims to secure high-risk chemical facilities against terrorism. Requirements of the program include assessing and reporting security risks and vulnerabilities, developing security plans, and compliance with security measures. Any facility storing certain amounts of AN must submit a top-screen survey application to DHS.
U.S. Environmental Protection Agency (EPA)
EPA’s Environmental Planning and Community Right to Know Act (EPCRA) requires facilities that are storing AN to submit Safety Data Sheets (SDS) to state and local first responders.
Maritime Transportation Security Administration (MTSA)
MTSA regulates any waterfront facility handling AN, and these facilities are required to have an approved Coast Guard security plan and follow all USCG regulations.
National Fire Protection Association (NFPA)
The NFPA has developed codes for the safe storage of AN for state and local fire marshals.
Industry Best Practices and Guidelines for Ammonium Nitrate
The Institute of Makers of Explosives (IME) has developed a series of best practices and guidelines for the safe and secure storage, use, and transport of explosive materials – including AN – called Safety Library Publications (SLPs).
IME SLP-2, the American Table of Distances, has been around for nearly 100 years and is written into ATF regulations that govern the storage of explosive material when located near AN. You may download a free copy of SLP-2 from our online store.
Other SLPs that pertain to AN include:
- IME SLP-28, Recommendations for Accountability and Security of Bulk Explosives and Bulk Security Sensitive Materials
- IME SLP-30, Safe Handling of Solid Ammonium Nitrate
- IME SLP-31, Methods and Algorithms Used for Quantitative Risk Analysis