An explosive is any substance or article, including a device, which is designed to function by explosion, i.e. an extremely rapid release of gas and heat, or which, by chemical reaction within itself, is able to function in a similar manner even if not designed to function by explosion, unless it is otherwise classified under the provision of the regulations.
Explosives in Class 1 are further divided into six divisions:
Division 1.1 – Explosives that have a mass explosion hazard, i.e. a mass explosion affects the entire load instantaneously.
Division 1.2 – Explosives that have a projection hazard but not a mass explosion hazard.
Division 1.3 – Explosives that have a fire hazard and either a minor blast hazard or minor projection hazard or both, but not a mass explosion hazard.
Division 1.4 – Explosives that present minor explosion hazard. The explosive effects are largely confined to the package and no projection or fragments of appreciable size or range are expected. An external fire must not cause virtually instantaneous explosion of almost the entire contents of the package.
Division 1.5 – Very insensitive explosives that have a mass explosion hazard but are so insensitive that there is little probability of initiation or of transition from burning to detonation under normal conditions of transport.
Division 1.6 – Extremely insensitive articles that do not have a mass explosive hazard and that contain only extremely insensitive detonating substances and demonstrate a negligible probability of accidental initiation or propagation.
The following list contains some examples of explosives, but is not all inclusive:
If there is a question as to whether the material you wish to ship is an explosive, notify DRS and ask to have a determination made.
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Division 2.1 - Flammable Gas – A material that is a gas at 20º C or below and 101.3 kPa of pressure (ambient temperature and pressure), i.e. the material has a boiling point of 20º C at sea level and:
Division 2.2 - Non-Flammable/Non-Poisonous Compressed Gas – A material or mixture that exerts in the packaging an absolute pressure of 280 kPa (40.6 psi) or greater at 20º C and does not meet the definition of Division 2.1 or 2.3. This includes compressed gas, liquefied gas, pressurized cryogenic gas, comporessed gas in solution, asphyxiant gas and oxidizing gas.
Division 2.3 – Gas Poisonous by Inhalation – A material that is a gas at 20º C or below and 101.3 kPa of pressure (ambient temperature and pressure), i.e. the material has a boiling point of 20º C at sea level and:
LC50 is the concentration that will cause death to 50% of a sample population of laboratory animals under specified conditions.
The following list contains some examples of compressed gases, but is not all inclusive:
| Division 2.1 Flammable | Division 2.2 | Division 2.3 Poisonous |
| Aerosols | Aerosols | Ammonia, anhydrous |
| LPG (propane) | Carbon dioxide | Boron trichloride |
| Acetylene | Most refrigerant gases (R124, R133, etc) | Boron trifluroide |
| Butane | CO2 fire extinguishers | Hydrogen sulfide |
| Some refrigerant gases (R152a, R1132a, etc) | Helium | Carbon monoxide |
| Ethylene | Nitrogen | Compressed coal gas |
| Hydrocarbon gases | Nitrous Oxide (also an oxidizer) | Cyanogen |
| Hydrogen | Oxygen (also an oxidizer) | Chlorine |
| Lighters | Rare gases and nitrogen mixtures | Phosgene |
| Methane | Xenon | Silicon tetrafluoride |
If there is a question as to whether the material you wish to ship is a compressed gas, or what division compressed gas it is, notify DRS and ask to have a determination made.
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Flammable liquids are:
Combustible liquids are a liquid that does not meet the definition of any other hazard class and has a flash point of > 60.5º C (141º F) and ≤ 93º C (200º F).
The following are exceptions to the Class 3 definition:
When offered for ground transport, a flammable liquid with a flash point ≥ 38º C (100º F) that does not meet the definition of any other hazard class may be reclassified as a combustible liquid. This means that non-bulk packages will be exempt from regulation when offered by ground.
The following list contains some examples of flammable/combustible liquids, but is not all inclusive:
If there is a question as to whether the material you wish to ship is flammable/combustible, notify DRS and ask to have a determination made.
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Division 4.1 – Flammable Solids are:
Division 4.2 – Spontaneously Combustible materials includes the following:
Division 4.3 – Dangerous When Wet materials are materials that, when in contact with water, are liable to become spontaneously flammable or to give off flammable or toxic gas at a rate of > 1L/kg of material/hr.
The following list contains some examples of Class 4 materials, but is not all inclusive:
| Flammable Solids | Spontaneously Combustible | Dangerous When Wet |
| Matches | Activated carbon | Alkaline earth metal alloys |
| Nitrocellulose membrane filters | Lithium alkyds | Aluminum powder |
| Pentaborane | Barium | |
| Silicon powder | Phosphorus | Calcium Hydride |
| Wetted explosives | Potassium sulfide, anhydrous | Calcium |
| Sulfur | Oily rags | Calcium carbide |
| Titanium Powder, wetted | Seed cake | Magnesium |
| Zinc resinate | Sodium sulfide, anhydrous | Lithium |
| Naphthalene | Butyl lythium | Sodium |
| Sodium Borohydride |
If there is a question as to whether the material you wish to ship is a class 4 material, notify DRS and ask to have a determination made.
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Division 5.1 Oxidizers are materials that can, generally by yielding oxygen, cause or enhance the combustion of other materials.
Division 5.2 – Organic Peroxides are any organic compounds containing oxygen in a bivalent –O-O- structure and which may be considered derivatives of hydrogen peroxide, where one or more of the hydrogen atoms have been replaced by organic radicals. Refer to §173.128 for exceptions.
The following list contains some examples of oxidizers and organic peroxides, but is not all inclusive:
If there is a question as to whether the material you wish to ship is an oxidizer or organic peroxide, notify DRS and ask to have a determination made.
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Poisonous or Toxic Materials are materials, other than a gas, known to be so toxic to humans as to pose a health hazard during transportation, or which, in the absence of adequate human toxicity data:
Toxins that are extracted from a living source like plant, animal, or bacteria are called biotoxins and could be considered toxic if the LD50 meets the criteria stated above.
Some examples of a Division 6.1 poisonous/toxic material are listed below, but this list is not all inclusive:
If there is a question as to whether the material you wish to ship is poisonous, toxic, or a biotoxin, notify DRS and ask to have a determination made.
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The following categories of materials constitute Division 6.2:
Infectious Substances (Division 6.2): A material known or reasonably expected to contain a pathogen. A pathogen is a micro-organism (including bacteria, viruses, rickettsiae, parasites, fungi) or other agent, such as a proteinaceous infectious particle (prion) that can cause disease in humans or animals.
Culture: An infectious substance containing a pathogen that is intentionally propagated. Culture does not include a human or animal patient specimen. Cultures may be categorized as category A or B depending on the microorganism concerned.
Regulated Medical Waste: Waste derived from the medical treatment of humans, or animals, or from biological research. Typically, regulated medical waste is classified as category B.
Patient Specimens: Human or animal materials collected directly from humans or animals and transported for research, diagnosis, investigational activities, or disease treatment or prevention. Patient specimens include excreta, secreta, blood and its components, tissue and tissue swabs, body parts, and specimens in transport media (e.g. transwabs, culture media, and blood culture bottles). Patient specimens that have a minimal likelihood of containing pathogens via professional judgment are exempt from the hazardous materials regulation but do have packaging requirements.
Biological Products: Derivations of living organisms and manufactured for use in the prevention, diagnosis, treatment, or cure of diseases in humans or animals and are certified by the USDA, FDA, or other national authority. Examples of biological products include certain viruses, therapeutic serums, toxins, antitoxins, vaccines, blood, and blood products.
If you wish to ship biological materials, please consult the Division of Research Safety Biological Safety Section via e-mail or call 333-2755. Additional training may be required. See Transport of Biological Materials for more information.
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For DOT requirements, radioactive material means any material having a specific activity greater than 0.002 microcuries per gram (µCi/g). The specific activity of a radionuclide means the activity of the radionuclide per unit mass of that nuclide. The specific activity of a material in which the radionuclide is essentially uniformly distributed is the activity per unit mass of the material.
If there is a question as to whether the material you wish to ship is a radioactive material, notify the DRS Radiation Safety Group and ask to have a determination made.
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Corrosive materials are liquids or solids that cause full thickness destruction of human skin at the site of contact within a specified period of time; or a liquid that has a severe corrosion rate on steel or aluminum based on criteria in §173.137(c)(2). A liquid is considered to have a severe corrosion rate if it corrodes steel (SAE 1020) or aluminum (non-clad 7075-T6) faster than 6.25 mm (0.246 in.) a year at a temperature of 55º C (131º F).
Corrosive materials may be acid or alkaline, organic or inorganic. The following list contains some examples of corrosives, but is not all inclusive:
If there is a question as to whether the material you wish to ship is corrosive, notify DRS and ask to have a determination made.
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Miscellaneous Hazardous Materials are materials that present a hazard during transportation but don’t meet the definitions of hazard classes 1 – 8. This includes:
Some examples of Class 9 materials are, but not limited to:
Elevated temperature material means a material which, when offered for transportation or transported in a bulk packaging, is one of the following:
Hazardous Substances are materials found in Appendix A to the HMT, identified in CERCLA as environmentally hazardous substances. A hazardous substance is a material that is packaged in a quantity ≥ the reportable quantity (RQ) listed for it in the Appendix.
Marine Pollutants are listed in Appendix B to the HMT. Some of these are also listed in the HMT. There are two main types of marine pollutants:
Severe marine pollutants are noted with “PP” in the SMP column of the marine pollutant list.
EPA defines hazardous waste as a solid waste that displays a hazardous characteristic (ignitability, corrosivity, reactivity, and toxicity) or a waste that is on one of the hazardous waste lists.
If there is a question as to whether the material you wish to ship is Class 9 miscellaneous hazardous material, notify DRS and ask to have a determination made.
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Examples of some forbidden materials include, but are not limited to:
If there is a question as to whether the material you wish to ship is a forbidden from transportation, notify DRS and ask to have a determination made.