Finding Chemical Identifiers

You need identifying information—names or identification numbers—for chemicals in order to find their datasheets in CAMEO 365betÓéŔÖ. 

Note:Ěý´ˇ UN/NA numberUnited Nations-North American number. (Also UN number or DOT number.) Four-digit number identifying an individual chemical or group of chemicals with similar characteristics. Required on shipping papers; often shown on placards. The four-digit number is often preceded by UN (such as UN1219). doesn't always indicate a single chemical. To be sure of identification, look for other identifiersNames, identification numbers, and other information used to identify a chemical., such as the shipping name. In general, use multiple sources for identificationuse multiple sources for identification

Shipping documents, labels, and placards sometimes contain errors. Chemical names are often misspelled on shipping documents, and a small difference of a letter or two can make a big difference. (For example, sulfide and sulfate refer to chemicals that greatly differ in hazardousness.) Identification numbers can be incorrect, labels can be faded or torn, and placards may be missing.

To catch such problems:

  • Check more than one source of information. For example, review the DCM as well as the cargo manifestDocument describing the contents of a shipment., checking for differences in name spellings and identification numbers.
  • Check that the identifiersNames, identification numbers, and other information used to identify a chemical. for a chemical match. For example, check that the shipping nameOr 'proper shipping name'. Either: (a) the specific name of a hazardous material that is frequently shipped (e.g., 'Ammonia, anhydrous'), or (b) the generic name for a less frequently shipped hazardous material, which categorizes the material by its family, its use, or a key characteristic (e.g., 'Acids, n.o.s.' or 'Flammable solids, n.o.s.'). and the UN/NA numberUnited Nations-North American number. (Also UN number or DOT number.) Four-digit number identifying an individual chemical or group of chemicals with similar characteristics. Required on shipping papers; often shown on placards. The four-digit number is often preceded by UN (such as UN1219). are for the same chemical.

Click on the links below to see tips on where to look for identifying information based on where the chemical is stored or transported:

  • AircraftAircraft
    • Pilot notification. This document describes all hazardous materials on board the aircraft. It must be readily available to the pilot-in-command during flight, and must list the shipping name and UN/NA number for each hazardous material on the aircraft. (There is no standard format for pilot notification.)
    • Shipping papers. Look for the shipping papers, which should be in the possession of the pilot-in-command, and also should list the name and UN/NA number for each hazardous material on board.
  • Fixed FacilityFixed Facility
    • Placards and tags. Tanks containing hazardous materials must be labeled or marked with the identity of the material (name and identification numbers, such as the UN/NA number) and hazard warnings (such as "flammableEasy to ignite and burns readily." or "causes lung damage"). Look on each container or storage tank for a placard, label, marking, or tag.
    • Hazardous materials list. This list of on-site hazardous materials must be posted in a prominent place.
    • Safety Data Sheets (SDSs). SDSs must be posted prominently in the same workspace as the materials, and may be kept in the facility's computer system. Ask 24-hour staff for the SDSs for substances of concern or look for a binder in a central location, a clipboard on the wall, or other reasonable locations. Look in each SDS for the name, UN/NA number, and often the CAS numberOr CAS #. Chemical Abstracts Service Registry number. This chemical identification number, in the format XXX-XX-X, is assigned by the American Chemical Society (www.cas.org/support/documentation/chemical-substances/faqs). for the material.
    • Emergency plan. The facility may have prepared a chemical emergency plan.

    For more information on containers at fixed facilities, see the Storage Tanks Reference Guide and the Drums and Portable Containers Reference Guide.

  • Intermodal Shipping ContainerIntermodal Shipping Container
    • Document tube. This tube may be mounted on the frame near the dataplate. It may contain documentation for the transported substance. Look for the substance's name and identification numbers in the documents in the tube.
    • Shipping papers or cargo manifest. Look for these shipping documents for the vessel or vehicle carrying the intermodal tank; the documents should list the name and UN/NA number for each hazardous material. Where can I find shipping papers or cargo manifests?
    • Stenciled name. The shipping name of the hazardous material may be stenciled on the tank.
    • Placards. DOT placards on the tank indicate the substance's main hazard and may also display the UN/NA number. Look for identical, diamond-shaped placards on the front, rear, and both sides of the tank. Sometimes the UN/NA number is included on the placard (or on an orange panel just below it). However, note that placards may be missing, and tanks may be incorrectly placarded. 
      At left, a sample DOT placard for isopropanol, where the placard indicates that the substance is in hazard class 3 (flammable and combustible liquids) and the UN/NA number (1219) has also been added to the placard. At right, the placard is shown without a UN/NA number. In such cases, the UN/NA number may be identified in an orange panel near the placard.
    • Hazard identification panel. Some intermodal tanks are placarded with an orange hazard identification panel displaying an international hazard identification code along with the UN/NA number for the tank contents. A sample intermodal tank placard, with a 33 in the international hazard identification code section (top) and a 1203 in the UN/NA number section (bottom).

    For more information on intermodal shipping containers, see the Intermodal Tanks Reference Guide.

  • Portable Tank, Drum, or PackagePortable Tank, Drum, or Package
    • Attached label or tag. Look on each container for markings or an attached label or tag showing (a) the shipping name of the substance in the container and (b) the UN/NA number for the hazardous material it contains.
    • Hazard label. Any hazmatHazardous material. container also should display a diamond-shaped label—either a pictogram or a smaller version of a DOT placard (showing the enclosed material's hazard class or division number), either of which indicates its hazards.
    • Shipping papers or cargo manifest. Look for these shipping documents for the vessel or vehicle carrying the portable container; the documents should list the name and UN/NA number for each hazardous material. Where can I find shipping papers or cargo manifests?

    For more information on portable containers, see the Drums and Portable Containers Reference Guide.

  • TrainTrain
    • Train consist. The consistA document showing the current positions of cars in a train and their cargo, including hazardous materials. document is carried by the conductor or engineer, and also should be in the railroad's computer system. It lists all cars in the train and the current positions of cars carrying hazardous materials.
    • Waybills. A waybill is issued for each rail car. It lists the shipper, consigneePerson (or business) to whom a shipment is sent., and car contents. Waybills should be kept by the conductor.
    • Stenciled name. For certain chemicals, the name of the hazardous material in the rail car is stenciled on both sides in 4-inch-high letters. For example, as the stenciled name shows in the picture below, this tank car carries liquefied petroleum gas (LPG).
      Liquefied petroleum gas is stenciled on this rail car, which also has a placard showing the primary hazard and UN/NA number for the chemical.
    • Placards. DOT placards on the rail car indicate the substance's main hazard and may also display the UN/NA number. Look for identical, diamond-shaped placards on the front, rear, and both sides of the rail car. Sometimes the UN/NA number is included on the placard (or on an orange panel just below it). However, note that placards may be missing, and rail cars may be incorrectly placarded.
      At left, a sample DOT placard for isopropanol, where the placard indicates that the substance is in hazard class 3 (flammable and combustible liquids) and the UN/NA number (1219) has also been added to the placard. At right, the placard is shown without a UN/NA number. In such cases, the UN/NA number may be identified in an orange panel near the placard.
    • Reporting marks. Each rail car is identified by a unique reporting mark: a combination of letters followed by numbers that is stenciled on both sides and both ends of the car. The sequence of letters identifies the railroad or company that owns the car, and the sequence of numbers identifies the car. As you face the side of the car, the reporting mark is to your left. You can call a car's reporting marks into CHEMTREC (800-424-9300) to identify the car's owner and—eventually—its contents. For example, as indicated on the picture by the red oval, the reporting mark on this rail car is GATX 55674.
      A tank car with the reporting mark GATX 55674.
    • DOT tank car specification markings. These markings (on both sides of the car) identify the class of tank car, which tells you what it could be carrying. Review the diagram below for information on how to decode a specification marking. For example, the first sequence of numbers (111 in the example below) tells you the car's class: non-pressure, pressure, high pressure, or cryogenicVery low temperature..
      Diagram explaining what each of the values in the marking indicate.

    For more information on trains, see the Rail Cars Reference Guide.

  • TruckTruck
    • Placards. DOT placards on the cargo tank or trailer indicate the substance's main hazard and may also display the UN/NA number. Look for identical, diamond-shaped placards on the front, rear, and both sides of the cargo tank (or the trailer if the truck isn't carrying a cargo tank). Sometimes the UN/NA number is included on the placard (or on an orange panel just below it). However, note that placards may be missing, and trucks may be incorrectly placarded.
      At left, a sample DOT placard for isopropanol, where the placard indicates that the substance is in hazard class 3 (flammable and combustible liquids) and the UN/NA number (1219) has also been added to the placard. At right, the placard is shown without a UN/NA number. In such cases, the UN/NA number may be identified in an orange panel near the placard.
    • Shipping papers. These papers must list and identify hazardous materials carried on the truck. Look for shipping papersDocuments used for billing, accountability, and other day-to-day activities involving the transport of hazardous materials. in the truck's cab. They could be in a pouch on the driver's door, within reach of the driver while they are driving, on the driver's seat when they are out of the vehicle, or with the driver during an emergency. Also look for the shipping papers for the hazardous materials carried on the truck. They should be marked with a tab or placed on top of other shipping papers.
    • Labels and tags on containers carried in a boxed trailer. Look on each container (or on an attached label or tag) for the shipping name—which should match the name shown on the shipping paper—and the UN/NA number for the hazardous material it contains. Each package should also display a diamond-shaped label with either a pictogram or a smaller version of a DOT placard (showing the enclosed material's hazard class or division number), either of which indicates its hazards.
    • Truck type. The type of truck is also a clue to its possible contents.

    For more information on trucks, see the Trucks Reference Guide.

  • Vessel or BargeVessel or Barge
    • Dangerous Cargo Manifest (DCM). This document lists the shipping name and UN/NA number for all hazardous materials transported on a vessel or barge. Look for the DCM in a holder on (or near) the bridge, in the possession of the captain or master. The DCM may be in a marked, tube-like container. A vessel's DCM must be submitted to the National Vessel Movement Center in advance of the vessel's arrival at a U.S. port.

A Note About Shipping Papers

In many cases, locating the shipping papersDocuments used for billing, accountability, and other day-to-day activities involving the transport of hazardous materials. is a good way to start identifying unknown—and possibly hazardous—chemicals. A shipping paper is a document used for day-to-day activities involved in the transport of hazardous materials. Shipping papers include bills of ladingContracts for transportation and receipt for cargo that a carrier gives to a seller when the carrier transports that seller's goods., cargo manifestsDocument describing the contents of a shipment., waybillsDocument accompanying a shipment, containing instructions for handling the shipment, description of the shipment, shipper and consignee information, and other details., and similar documents.

Shipping papers come in a variety of formats, but each includes the following information about any hazardous material in the shipment: UN/NA number, proper shipping nameEither: (a) the specific name of a hazardous material that is frequently shipped (e.g., 'Ammonia, anhydrous'), or (b) the generic name for a less frequently shipped hazardous material, which categorizes the material by its family, its use, or a key characteristic (e.g., 'Acids, n.o.s.' or 'Flammable solids, n.o.s.')., hazard class or division, and packing groupMost hazardous materials are assigned a packing group, which indicates degree of hazard. Packing groups are indicated as either I, II, or III, with I representing the most severe hazard and III the least severe hazard. The packing group of a hazardous material must be shown on shipping papers.. An example is shown below. See the Shipping Papers Reference Guide and the Dangerous Cargo Manifests Reference Guide for more information.

An example of a shipping paper for benzene, with the UN/NA number, shipping name, hazard class, and packing group marked.