Colorado CDL Hazmat key terms

Any substance or material that the Secretary of Transportation has determined can pose an unreasonable risk to health, safety, or property when transported in commerce. This includes materials meeting any of the nine hazard classes.

One of nine categories (explosives, gases, flammable liquids, flammable solids, oxidizers, toxic and infectious substances, radioactive, corrosive, miscellaneous) used to group materials by their dominant transportation hazard.

A subdivision within a hazard class that further refines the type or degree of hazard, such as Division 1.1 for mass-detonating explosives or Division 6.1 for toxic materials.

A Roman numeral (I, II, or III) assigned to many hazardous materials indicating the degree of danger: I is great danger, II is moderate danger, and III is minor danger.

Materials regulated under environmental rules that are being shipped for disposal, treatment, or storage. They require a hazardous waste manifest, and placards may be required depending on the quantity and characteristics.

A hazardous material that regulations prohibit from being offered or transported in commerce under any circumstances, or only under specific exceptions. Carriers must refuse such shipments.

A person who directly affects hazardous materials transportation safety, including drivers, loaders, and those who prepare shipping papers or handle packaging. Such employees require general awareness, function-specific, and safety training.

A person or business that uses employees in hazardous materials transportation, including self-employed drivers. The employer must provide required training, certify compliance, and keep training records.

The documentation that accompanies a hazardous materials shipment, describing the material, quantity, and hazard. It must be readily accessible to the driver and to emergency responders during transport.

The required sequence on a shipping paper: the proper shipping name, hazard class or division, UN or NA identification number, and packing group in that order, followed by quantity information.

The recognized name of a hazardous material as listed in the hazardous materials table. Drivers and shippers must use this exact name rather than a common or trade name.

A four-digit number preceded by UN or NA that identifies a specific hazardous material or group of materials, such as UN1203 for gasoline. It appears on shipping papers and in some markings.

Information that must accompany a hazardous materials shipment and be available for use in an incident, describing immediate hazards, firefighting or spill response, and first aid measures.

A reference book organized by UN identification number and material name that provides initial isolation distances, protective actions, and fire or spill guidance for responders to hazardous materials incidents.

A diamond-shaped warning sign placed on the outside of a vehicle or container to identify the hazard class of its contents. Placards are required above certain quantity thresholds or for specific materials.

A placard required for a material listed in the placarding table regardless of quantity, such as certain explosives, poisonous gases, or dangerous when wet materials, unless a specific exception applies.

A placard used when a vehicle carries 1,001 pounds or more aggregate gross weight of materials from one hazard class, or when the material is in a bulk package, even if not listed in the placarding table.

A smaller warning sign affixed to individual packages identifying the hazard class of the contents. Labels communicate the hazard to handlers and must match the material inside.

Required text or symbols on packaging identifying the proper shipping name and UN identification number, along with required package specification markings. Markings differ from labels and placards.

A packaging with a capacity greater than 119 gallons for liquids, 882 pounds for solids, or 1,000 pounds of water capacity for gases. Bulk shipments trigger different placarding and handling rules.

A bulk packaging attached to or forming part of a motor vehicle, used to transport liquid or gaseous hazardous materials. Cargo tanks require special inspection, marking, and loading procedures.

A commercial motor vehicle with a cargo tank, portable tank, or other bulk container of 119 gallons or more used for liquids or gases. Drivers need a tank vehicle endorsement to operate one.

A bulk container not permanently attached to the vehicle, designed to be loaded and unloaded as a unit. It must meet specification requirements and be secured against movement during transport.

The practice of keeping incompatible hazardous materials apart during loading and transport to prevent dangerous reactions such as fire, explosion, or toxic gas release if packages leak or break.

Materials that could react dangerously if they mix, such as oxidizers with flammables or acids with cyanides. They must not be loaded together unless separated as regulations allow.

The use of tiedowns, blocking, bracing, or other devices to prevent packages and containers from shifting, sliding, or tipping during transport, which is critical for heavy and bulk hazmat loads.

Remaining within view of the vehicle and close enough to prevent unauthorized entry or movement. Hazmat loads often require the driver to attend the vehicle rather than leave it unattended.

Restrictions on where a placarded vehicle may be parked, generally prohibiting parking within 5 feet of the traveled portion of a public street or highway unless the vehicle is attended.

A rule prohibiting certain placarded hazardous materials vehicles from entering tunnels or requiring specific routing, based on posted signs and the hazard class being carried.

Selecting a travel path that avoids restricted tunnels, bridges, and densely populated areas where possible, and that follows any required designated routes for hazardous materials.

An intersection of roadway and train tracks where hazmat vehicles must stop before crossing unless exempted, and must never block the tracks while waiting in traffic.

The requirement to notify authorities after a hazardous materials release involving death, injury, evacuation, or specified quantities. Reports go to the National Response Center and state or local agencies.

Immediate actions after a release, including stopping the vehicle safely, keeping people away, preventing ignition, and contacting emergency services. Drivers should not attempt cleanup beyond their training.

The initial distance responders should keep people away from a hazardous materials release, often specified in the emergency response guidebook by material and incident size.

A special endorsement on a commercial driver license required to operate a vehicle carrying hazardous materials that require placarding. It requires a knowledge test and a security threat assessment.