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Below is a list of the sections that have interpretations available for the selected category. To view the interpretations for a given section, click on the subject link below. To return to the list of Parts, use the Parts link above. Finally, these interpretations are specific to the scenarios in which they are responding to and may not be applicable to different fact scenarios.

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Section Subject
172.502 Prohibited and permissive placarding
172.503 Identification number display on placards
172.504 General placarding requirements
172.505 Placarding for subsidiary hazards
172.506 Providing and affixing placards: Highway
172.508 Placarding and affixing placards: Rail
172.510 Special placarding provisions: Rail
172.512 Freight containers and aircraft unit load devices
172.514 Bulk packagings
172.516 Visibility and display of placards
172.519 General specifications for placards
172.522 EXPLOSIVES 1.1, EXPLOSIVES 1.2 and EXPLOSIVES 1.3 placards
172.532 FLAMMABLE GAS placard
172.540 POISON GAS placard
172.542 FLAMMABLE placard
172.544 COMBUSTIBLE placard
172.550 OXIDIZER placard
172.556 RADIOACTIVE placard
172.558 CORROSIVE placard
172.560 CLASS 9 placard
172.600 Applicability and general requirements
172.602 Emergency response information
172.604 Emergency response telephone number
172.606 Carrier information contact
172.700 Purpose and scope
172.701 Federal-State relationship
172.702 Applicability and responsibility for training and testing
172.704 Training requirements
172.800 Purpose and applicability
172.802 Components of a security plan
172.804 Relationship to other Federal requirements
173.1 Purpose and scope
173.2 Hazardous materials classes and index to hazard class definitions
173.2a Classification of a material having more than one hazard
173.3 Packaging and exceptions
173.4 Small quantities for highway and rail
173.4a Excepted quantities
173.4b De minimis exceptions
173.5 Agricultural operations
173.5a Oilfield service vehicles, mechanical displacement meter provers, and roadway striping vehicles exceptions
173.6 Materials of trade exceptions
173.7 Government operations and materials
173.8 Exceptions for non-specification packagings used in intrastate transportation
173.9 Transport vehicles or freight containers containing lading which has been fumigated
173.10 Tank car shipments
173.11 Exceptions for shipment of light bulbs containing hazardous materials
173.12 Exceptions for shipment of waste materials
173.13 Exceptions for Class 3, Divisions 4.1, 4.2, 4.3, 5.1, 6.1, and Classes 8 and 9 materials
173.21 Forbidden materials and packages