a four digit number representing a particular chemical or group of chemicals (eg
a four-digit number assigned to hazardous material required by the DOT for highway transportation, by IMDG for water transit, and by ICAO for air. It is used to help designate the emergency response procedure in the event of a spill or release.
United Nations Substance Identification Number (for transport purposes).
United Nations substance numbers are four-digit numbers, which have been assigned by the United Nations Committee of Experts on the Transport of Dangerous Goods, to individual substances (e.g. sulphuric acid) or groups of similar substances (e.g. carbamate pesticides). The numbers are primarily intended to facilitate the identification of substances without the need for a knowledge of the language in which the chemical name is printed. They have also proved to be of great value for emergency services in the correct relaying of long or complex names of substances, thus allowing error-free identification
A numbering system recommended by the United Nations Committee of Experts on the Transport of Dangerous Goods for the aim of worldwide harmonization in this field. Up to Top
a four digit number assigned to a potentially hazardous material or class of materials. UN ( United Nations) numbers are internationally recognized and are used by fire fighter and other emergency response personnel for identification of materials during transportation emergencies. NA ( North American) numbers are assigned by Transport Canada and the US Department of Transport to materials they consider hazardous and to which a UN number has not been assigned.
The DOT (Department of Transportation) Number found on the Cylinder (bottle) label. For example UN1066, the "UN" prefix to this number indicates that 1066 is recognized throughout the world as identifying nitrogen. Sometimes "NA" (North America) will appear as a prefix. NA numbers are recognized in the USA and Canada.
UN numbers or UN IDs are four-digit numbers that identify dangerous goods hazardous substances and articles (such as explosives, flammable liquids, toxic substances, etc.) in the framework of international transport. Some hazardous substances have their own UN numbers (e.g. acrylamide has UN2074), while sometimes groups of chemicals or products with similar properties receive a common UN number (e.g. flammable liquid, not otherwise specified, have UN1993). A chemical in its solid state may receive a different UN number than the liquid phase if their hazardous properties differ significantly; substances with different levels of purity may also receive different UN numbers.