49 CFR § 173.2
Hazardous materials classes and index to hazard class definitions
November 18, 2020
The hazard class of a hazardous material is indicated either by its class (or division) number, its class name, or by the letters “ORM-D”. The following table lists class numbers, division numbers, class or division names and those sections of this subchapter which contain definitions for classifying hazardous materials, including forbidden materials.
Open Table
Class No. | Division No. (if any) | Name of class or division | 49 CFR reference for definitions |
---|---|---|---|
None | Forbidden materials | 173.21 | |
None | Forbidden explosives | 173.54 | |
1 | 1.1 | Explosives (with a mass explosion hazard) | 173.50 |
1 | 1.2 | Explosives (with a projection hazard) | 173.50 |
1 | 1.3 | Explosives (with predominately a fire hazard) | 173.50 |
1 | 1.4 | Explosives (with no significant blast hazard) | 173.50 |
1 | 1.5 | Very insensitive explosives; blasting agents | 173.50 |
1 | 1.6 | Extremely insensitive detonating substances | 173.50 |
2 | 2.1 | Flammable gas | 173.115 |
2 | 2.2 | Non-flammable compressed gas | 173.115 |
2 | 2.3 | Poisonous gas | 173.115 |
3 | Flammable and combustible liquid | 173.120 | |
4 | 4.1 | Flammable solid | 173.124 |
4 | 4.2 | Spontaneously combustible material | 173.124 |
4 | 4.3 | Dangerous when wet material | 173.124 |
5 | 5.1 | Oxidizer | 173.127 |
5 | 5.2 | Organic peroxide | 173.128 |
6 | 6.1 | Poisonous materials | 173.132 |
6 | 6.2 | Infectious substance (Etiologic agent) | 173.134 |
7 | Radioactive material | 173.403 | |
8 | Corrosive material | 173.136 | |
9 | Miscellaneous hazardous material | 173.140 | |
None | Other regulated material: ORM-D | 173.144 |
[Amdt. 173-224, 55 FR 52606, Dec. 21, 1990, as amended at 57 FR 45460, Oct. 1, 1992; Amdt. 173-234, 58 FR 51531, Oct. 1, 1993]