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Code of Federal Regulations Title 49. Transportation § 49.173.2 Hazardous materials classes and index to hazard class definitions

Current as of January 02, 2025 | Updated by Findlaw Staff

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.

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
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Cite this article: FindLaw.com - Code of Federal Regulations Title 49. Transportation § 49.173.2 Hazardous materials classes and index to hazard class definitions - last updated January 02, 2025 | https://codes.findlaw.com/cfr/title-49-transportation/cfr-sect-49-173-2/

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