IME to Press UN to Clarify Definition of AN (UN 0222) to Prevent Misinterpretation & Misapplication


The Institute of Makers of Explosives (IME) officially declared its intent to press for an update to the definition of UN 0222 Ammonium Nitrate later this fall when it officially submitted a formal proposal for consideration at the 54th session of the United Nations Sub-Committee of Experts on the Transport of Dangerous Goods (TDG).  IME is a Non-Governmental Organization (NGO) participant of the TDG and will be present at the upcoming meeting in Geneva, Switzerland from November 26th through December 4th, 2018. 

The proposal clarifies the use of the UN 0222 Ammonium Nitrate (1.1D) Dangerous Goods List entry as a classification for ammonium nitrate.  For example, if one did not know that UN 0222 was for non-commercially available AN, then one could mistakenly believe the entry could cover ANFO.  In other instances, due to its place at the beginning of several entries for AN, UN 0222 has been found to be misapplied, leading to confusion and delay until the error is corrected.  If adopted by the TDG, the clarification will prevent misapplication, misidentification, and will help regulatory agencies clearly identify and define in their regulations the extent of their jurisdiction, if any, over AN. 

If adopted during the 54th Session, the proposed clarification would be published in the 21st revision of the TDG’s Model Regulations that should be available by mid-2019.   After publication, in order to make it effective in the United States, the clarification must then be included into the US Department of Transportation’s Hazardous Materials Regulations (HMR), following their normal notice and comment procedures.  While updating the HMR has become routine, IME would be expected to closely monitor the process to ensure the proper outcome. 

The proposal, document number ST/SG/AC.10/C.3/2018/68, may be downloaded from the TDG’s working document website at:

More information on the work of IME can be found at