U.S. Department of Labor

Assistant Secretary for
Occupational Safety and Health
Washington, D.C. 20210

DOL Logo

February 10, 2014

Dear Fertilizer Industry Employer:

On April 17, 2013, a fire began in a warehouse at the West Fertilizer Company in West, Texas. About 20 minutes after the first report of a fire, during the initial mobilization of firefighting personnel, bulk ammonium nitrate stored in an adjacent warehouse exploded, killing 15 including 12 emergency response personnel.

On September 21, 2001, in Toulouse, France, a pile of off-specification granular ammonium nitrate exploded due to unknown causes killing 31 and causing billions of euros in damage.

On April 16, 1947, in Texas City, Texas, the transport vessel Grandcamp loaded with about 2600 tons of bagged ammonium nitrate caught fire. The fire spread to the sealed cargo hold and the ammonium nitrate stored within exploded killing 581 including all but one member of the Texas City fire Department.

These incidents, spanning 66 years, and many others not listed here, highlight the potential hazards involved in storing and handling ammonium nitrate. While millions of pounds of ammonium nitrate are safely shipped, stored, blended, and used nationally every year, these incidents remind us that ammonium nitrate can be deadly when the material is handled or stored poorly and not in accordance with industry safe practices.

The Occupational Safety and Health Administration (OSHA) is sending this letter to remind you of your responsibility as an employer to prevent these tragic explosions by manufacturing, storing, distributing, and using ammonium nitrate in a safe manner.  

In October, OSHA cited the owners of the West Fertilizer Company, with 24 serious safety violations including exposing workers ammonium nitrate fire and explosion hazards. The tragic loss of 15 lives, including 12 first responders, underscores the need for employers who store and handle hazardous substances like ammonium nitrate to ensure the safety of those material — not just for the workers at the facility, but for the lives and safety of emergency responders and nearby residents. A copy of the citations can be found at http://www.osha.gov/pls/imis/establishment.inspection_detail?id=901718.015.

Many information resources exist to assist you. The federal government, industry groups, and consensus standard organizations have all prepared standards or guidelines on safely storing and handling ammonium nitrate.

  • OSHA 29 CFR 1910.109(i) - Storage of Ammonium Nitrate,
  • Joint EPA-OSHA-ATF guidance - Chemical Advisory: Safe Storage, Handling, and Management of Ammonium Nitrate,
  • Joint Institute of Makers of Explosives and National Stone, Sand, and Gravel Association guidance - Safety and Security Guidelines for Ammonium Nitrate,
  • The National Fire Protection Association Hazardous Materials Code (NFPA 400) chapter 11 on ammonium nitrate.

You can find these and other resources on a web page OSHA prepared for your use. Go to http://www.osha.gov/dep/fertilizer_industry/index.html. The resources on the web page provide employers with the necessary requirements and recommendations for safely storing and handling ammonium nitrate including:

  • Building construction
  • Fire protection
  • Bulk storage to prevent contamination
  • Storage to prevent fires from impacting piles of ammonium nitrate
  • Storage building separation and siting
  • Emergency response

OSHA enforcement personnel will enforce the requirements of 29 CFR 1910.109(i) for storage of ammonium nitrate including those facilities in non-explosives industries. OSHA standards set minimum safety and health requirements; the standards do not preclude employers from adopting more stringent requirements.

I am calling on you today to take the necessary steps to prevent tragic ammonium nitrate incidents. If you are a small- or medium-sized business, free consultation programs are available to assist you in complying with OSHA standards. If you have further questions please contact your local OSHA area or state plan office. More information is available at www.osha.gov.



David Michaels, PhD, MPH