A placarded vehicle must have at least four identical placards: one on the front, one on the rear, and one on each side of the vehicle.

On a compressed gas tank, liquid discharge valves must always be kept closed, except during loading and unloading.

You must examine each tire on a motor vehicle at the beginning of each trip. The only effective way to check tire pressure is by using a tire pressure gauge.

Shippers of hazardous materials are required to warn drivers and others about the risks of the materials by putting hazard warning labels on packages, putting placards on the transporting vehicles, and providing proper shipping papers and emergency response information.

If you are involved in an accident while carrying hazardous materials, it is your responsibility as the driver to keep people away from the scene; limit the spread of material if you can safely do so; inform emergency response personnel of the dangers posed by the materials; and provide emergency personnel with the shipping papers and emergency response information. Unless you have protective equipment and the necessary training, do not try to fight hazardous materials fires yourself.

Among other information, shipping papers must include a description of the specific hazardous materials being transported.

A hazardous material will be placed into one of nine classes to explain the type of risks associated with the material.

The power unit of a placarded vehicle must be equipped with a fire extinguisher with an Underwriters Laboratories (UL) rating of 10 B:C or more.

Shippers package hazardous materials in a way that is meant to completely contain the materials. Vehicles should be placarded to communicate the risk of the cargo.

Diamond-shaped signs called placards are placed on bulk packages and on the outside of vehicles to warn drivers and others of the presence of hazardous materials. It is the responsibility of the shipper to place the placards, and it is the responsibility of the driver to verify that the correct placards have been placed.

Always protect containers of hazardous materials. When loading hazardous materials, never use equipment that could damage containers or packaging, such as hooks.

When applying for an original or renewed HazMat endorsement, you must undergo a federal security threat assessment done by the Transportation Security Administration (TSA).

If transporting chlorine in cargo tanks, a driver must have an approved gas mask in their vehicle.

Shippers should place applicable diamond-shaped hazard warning labels on hazardous materials packages. If a label will not fit entirely onto a package, shippers may instead place the label on a tag that is securely attached to the package.

If loading by hand, load breakable containers of corrosive liquid one by one. Keep them facing upright. Do not drop or roll the containers.

Information about hazardous chemicals is found in the Emergency Response Guide (ERG) provided by U.S. Department of Transportation (DOT). The ERG is indexed by the proper shipping names and identification numbers of substances.

If you need to refuel a vehicle carrying hazardous materials, you must first turn off the engine. While refueling, someone must be at the nozzle and controlling the fuel flow at all times.

Radiation will surround each package of radioactive materials and pass through to all nearby packages. The number of packages that can be loaded together is controlled.

When carrying Division 1.1, 1.2, or 1.3 explosives, do not park within 300 feet of a bridge, tunnel, or building; a place where people gather; or an open fire.

A material's ID number must appear on its accompanying shipping paper as well as on its packaging. It also must appear on cargo tanks and other bulk packaging.

Packages that contain liquid containers must have orientation markers. Arrows displayed on the box should be pointing in the correct upright direction.

While the manual includes all of the information required to pass the hazardous materials knowledge test, you should consider reading the manual as only the first step to learning about the topic. You can learn more by reading and understanding the federal and state rules about the transportation of hazardous materials, as well as by attending hazardous materials training courses.

When experiencing a cargo fire, it may be a bad idea to open the doors to the trailer. Doing so allows oxygen to enter the area, potentially causing the fire to flare up and expand.

Fighting a hazardous materials fire requires special training and protective gear. Unless you have the proper equipment and training, do not try to fight a hazardous materials fire yourself.

If a cargo of hazardous materials begins to leak, do not move your vehicle any more than safety requires. If you continue to drive, an even larger area will become contaminated. Instead, you should park your vehicle, secure it, stay with the vehicle, and contact the proper emergency personnel. If you do not have access to a phone, you should send someone else to get help.

You should use a floor lining when transporting Division 1.1, 1.2, or 1.3 materials. The floors must be tight and the liner must be made from either non-metallic material or non-ferrous metal. Non-ferrous metals are any metals that do not contain iron or iron alloys.

It is always a good idea to compare package markings and labels to accompanying shipping papers. Always make sure the shipper has displayed the correct basic description on the shipping paper and has provided the proper labels on the packages.

If you are experiencing a truck fire, you should not attempt to open trailer doors without first feeling the doors to see if they are hot. If the doors are hot, there may be a cargo fire. Leave the doors closed if there is a cargo fire.

If transporting any amount of chlorine, a driver must always stop at a railroad crossing 15 to 50 feet from the nearest track, regardless of the presence of a train.

If you discover a cargo leak while transporting hazardous materials, use the shipping papers, label, or package location to identify which materials are involved. Do not try to touch or smell the leaking materials to determine what they are because doing so could result in injury or death.