Alabama CDL HazMat key terms

Any substance or material that the Secretary of Transportation has determined is capable of posing an unreasonable risk to health, safety, or property when transported in commerce.

One of nine broad categories into which regulated materials are grouped by their dominant hazard, such as explosives, flammable liquids, or corrosives. Some classes are further split into divisions.

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

A letter assigned to explosives within Class 1 that identifies materials considered safe to store or transport together without creating an added hazard.

A two- or three-digit code shown on some tank cars and bulk packages that tells emergency responders the general hazard type and, when doubled, the intensity of that hazard.

A four-digit number, often preceded by the letters UN or NA, that identifies a specific hazardous material on shipping papers, packages, and placards.

The official name of a hazardous material as listed in the hazardous materials table, used on shipping papers and package markings to identify the material precisely.

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

A Roman numeral (I, II, or III) assigned to a material showing its degree of danger, with I being the greatest hazard and III the least.

The documentation that must accompany a hazardous materials shipment, describing the material, quantity, shipper, and emergency response information for use during transport and in an incident.

Guidance that must accompany hazardous materials shipping papers, such as a guidebook page or emergency contact number, so responders know how to handle a spill or fire.

A reference book, carried by many hazmat drivers, that lists materials by identification number and gives initial isolation distances and first-response actions for incidents.

A diamond-shaped warning sign affixed to a vehicle or bulk package that communicates the hazard class of its contents to emergency responders and the public.

The regulatory chart that specifies, for each hazard class and quantity, whether a placard is required, may be used, or is forbidden.

The threshold under which a shipment of a Table 2 material weighing 1,001 pounds or more, including the packaging, must be placarded.

A placard used for materials in certain hazard classes when shipped in bulk or in large quantities, indicating the load carries regulated dangerous goods.

Required identification applied directly to a package, such as the proper shipping name, UN number, or orientation arrows, to inform handlers about its contents and handling needs.

A smaller warning decal placed on individual packages that shows the hazard class or division of the material inside, distinct from a vehicle placard.

A packaging, other than a vessel or barge, with a capacity greater than 119 gallons for liquids or 882 pounds for solids, used to hold large quantities of material.

A bulk packaging permanently attached to a motor vehicle, used to transport liquid or gaseous hazardous materials and subject to special loading, unloading, and driving rules.

A bulk packaging that is not permanently attached to a vehicle and can be loaded, unloaded, and carried as a unit, such as an intermodal tank container.

A vehicle that carries a cargo tank or portable tank with a capacity of 1,000 gallons or more, or multiple tanks totaling that capacity, triggering additional licensing and operating requirements.

The practice of keeping incompatible hazardous materials apart during loading and transport so that a leak, fire, or reaction in one does not endanger the other.

Materials that, if mixed or brought together, could react dangerously, such as by generating heat, fire, toxic gas, or pressure, and therefore must be kept separated.

The requirement that packages be blocked, braced, or otherwise restrained so they cannot shift, tip, or fall during normal driving, braking, or evasive maneuvers.

A person who stays with a parked vehicle carrying hazardous materials when required, remaining awake, alert, and able to move the vehicle if necessary.

Restrictions on where and how long a hazmat vehicle may be parked, generally requiring it to be off public roads, away from populated areas, and attended or secured.

A pre-designated location where a driver can stop and park a hazardous materials load during an emergency, breakdown, or severe weather, reducing risk to the public.

A written plan required for certain high-risk hazmat shipments that describes measures to protect the material from theft, sabotage, or other unlawful interference.

The driver's ongoing attention to suspicious persons, vehicles, or activity around a hazmat load, and the practice of reporting concerns to the carrier or authorities.

The amount of a hazardous substance released that triggers mandatory notification to the National Response Center and other authorities under environmental law.

The duty to notify the carrier and, in serious cases, emergency authorities after a hazmat release, fire, or accident, providing details such as location, material, and injuries.

The federal point of contact that receives reports of hazardous material releases and relays them to the appropriate response agencies.

A special addition to a commercial driver's license, requiring a knowledge test and a security threat assessment, that authorizes driving vehicles carrying hazardous materials.

A rule that limits hazmat vehicles to certain roads or prohibits them from tunnels, bridges, or populated areas to reduce risk to the public.

The rule that drivers and handlers must not smoke or carry lighted smoking materials near a vehicle carrying hazardous materials, especially flammables and oxidizers.