Nitric acid should not be stacked above any other product. Containers of nitric acid may be stacked, but no higher than two containers high.

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.

Hazardous materials placards are placed on the outside of a vehicle to identify the hazard classes of materials being carried.

Hazardous materials are products that pose risks to health, safety, and property during transportation. Materials that are considered hazardous include explosives; flammable and poisonous gases; and flammable and other hazardous solids.

You should examine your tires at the beginning of every trip and after every stop to ensure that they are properly inflated. The only acceptable way to check tire pressure is to use a tire pressure gauge.

When the vehicle is being driven, hazardous materials' shipping papers must be kept in a pouch on the driver's door or somewhere else that is in clear view and within the driver's reach. If the driver is outside of the vehicle, the shipping papers should be kept on the driver's seat.

When loading hazardous materials, do not use hooks or tools that could damage containers or other packaging.

For some hazardous materials, placards are only required to be used if 1,001 pounds or more are being carried by a vehicle. For others, including mass explosives, placards are required to be used when carrying any amount of the material.

Always turn the engine off before refueling a vehicle carrying hazardous materials. Someone must always be at the nozzle controlling the fuel flow.

You must have a commercial driver license with a hazardous materials endorsement before driving a vehicle of any size that is used to transport hazardous materials, even if the vehicle is not transporting hazardous materials at the time of operation.

It is the responsibility of a carrier to refuse improper shipments of hazardous materials.

There are nine different classes of hazardous materials. A class reflects the risks associated with a type of material.

When carrying Division 1.1, 1.2, or 1.3 explosives, you should never park within five feet of the traveled portion of the road. Except when parking for short periods to address vehicle necessities, you should not park within 300 feet of a bridge, tunnel, or building; a place where people gather; or an open fire.

The person in charge of loading or unloading a hazardous materials cargo tank must ensure that a qualified person is always supervising the process. The supervisor must be alert; have a clear view of the tank; be within 25 feet of the tank; know the hazards of the involved materials; know the procedures to follow in the case of an emergency; and be authorized to and capable of moving the tank.

A driver transporting chlorine in cargo tanks must keep an approved gas mask and an emergency kit in their vehicle.

Radiation surrounds packages of radioactive materials and passes through to other nearby packages. To address this, the number of radioactive packages that can be loaded together is limited.

Shippers of hazardous cargo must alert drivers and others to relevant hazards through proper shipping papers, hazard warning labels on packages, emergency response information, and placards.

Always turn off your vehicle's engine before loading or unloading explosive materials. Never drop, throw, or roll packages containing explosives.

A vehicle must be properly placarded before it can be driven. A vehicle that does not display the proper placards may not be moved unless doing so is necessary to protect life or property in an emergency.

A vehicle with tanks that are used to transport hazardous materials must always be stopped before being driven over railroad tracks, even if the tanks are empty.

While the manual contains all of the information needed to pass the written exam for a hazardous materials endorsement, it does not contain all of the information necessary to do the job safely. You can learn more by attending hazardous materials training courses.

If a cargo leak develops while you are carrying hazardous materials, do not continue driving any farther than safety requires. The farther you drive, the larger the contaminated area will become. You should park the vehicle, secure the area, and stay with the vehicle while sending someone else to get help.

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

Flammable gases are assigned to hazardous materials Class 2.

When hazardous materials placards are required, they must be placed on all four sides of the vehicle.

When marking hazardous materials in an "HM" column on a shipping paper, the letters "RQ" may be used instead of an "X" if a reportable quantity of the material must be identified.

Shipping papers for hazardous materials should always be easily accessible. When a driver is not in their vehicle, hazardous materials' shipping papers should be left on the driver's seat.

Many hazardous materials become more dangerous when exposed to heat. Hazardous materials should be loaded and unloaded away from heat sources.

If a shipping paper describes both hazardous and non-hazardous materials, the hazardous materials must be distinguished in one of three ways. They must be entered first on the shipping paper, highlighted in a contrasting color, or marked with an "X" in a column titled "HM."

Radioactive materials are categorized as Class 7 hazardous materials.