Who Does What & Communication Rules

9.1 – The Intent of the Regulations

9.1.1 – Contain the Material

Transporting hazardous materials can be risky. The regulations are intended to protect you, those around you, and the environment. They tell shippers how to package the materials safely and drivers how to load, transport, and unload the material. These are called “containment rules.”

9.1.2 – Communicate the Risk

To communicate the risk, shippers must warn drivers and others about the material’s hazards. The regulations require shippers to put hazard warning labels on packages, provide proper shipping papers, emergency response information, and placards. These steps communicate the hazard to the shipper, the carrier, and the driver.

9.1.3 – Assure Safe Drivers and Equipment

In order to get a hazardous materials endorsement on a CDL, you must pass a written test about transporting hazardous materials. To pass the test, you must know how to:

  • Identify what are hazardous materials.
  • Safely load shipments.
  • Properly placard your vehicle in accordance with the rules.
  • Safely transport shipments.

Learn the rules and follow them. Following the rules reduces the risk of injury from hazardous materials. Taking shortcuts by breaking rules is unsafe. Non-compliance with regulations can result in fines and jail.

Inspect your vehicle before and during each trip. Law enforcement officers may stop and inspect your vehicle. When stopped, they may check your shipping papers, vehicle placards, and the hazardous materials endorsement on your driver license, and your knowledge of hazardous materials.

9.2 – Hazardous Materials Transportation—Who Does What

9.2.1 – The Shipper

  • Sends products from one place to another by truck, rail, vessel, or airplane.
  • Uses the hazardous materials regulations to determine the product’s:
  • Identification number.
  • Proper shipping name.
  • Hazard class.
  • Packing group.
  • Correct packaging.
  • Correct label and markings.
  • Correct placards.
  • Must package, mark, and label the materials; prepare shipping papers; provide emergency response information; and supply placards.
  • Certify on the shipping paper that the shipment has been prepared according to the rules (unless you are pulling cargo tanks supplied by you or your employer).

9.2.2 – The Carrier

  • Takes the shipment from the shipper to its destination.
  • Prior to transportation, checks that the shipper correctly described, marked, labeled, and otherwise prepared the shipment for transportation.
  • Refuses improper shipments.
  • Reports accidents and incidents involving hazardous materials to the proper government agency.

9.2.3 – The Driver

  • Makes sure the shipper has identified, marked, and labeled the hazardous materials properly.
  • Refuses leaking packages and shipments.
  • Placards vehicle when loading, if required.
  • Safely transports the shipment without delay.
  • Follows all special rules about transporting hazardous materials.
  • Keeps hazardous materials shipping papers and emergency response information in the proper place.

9.3 – Communication Rules

9.3.1 – Definitions

Some words and phrases have special meanings when talking about hazardous materials. Some of these may differ from meanings you are used to. The words and phrases in this section may be on your test. The meanings of other important words are in the glossary at the end of Section 9.

A material’s hazard class reflects the risks associated with it. There are nine different hazard classes. The types of materials included in these nine classes are in Figure 9.1.

Hazardous Materials Class



Name of Class or Division




Mass Explosion



Projection Hazard



Fire Hazard

Display Fireworks


Minor Explosion



Very Insensitive

Blasting Agents


Extremely Insensitive

Explosive Devices



Flammable Gases



Non-Flammable Gases



Poisonous/Toxic Gases

Fluorine, Compressed


Flammable Liquids




Flammable Solids

Ammonium Picrate, Wetted


Spontaneously Combustible

White Phosphorus


Dangerous When Wet





Ammonium Nitrate


Organic Peroxides

Methyl Ethyl Ketone Peroxide



Poison (Toxic Material)

Potassium Cyanide


Infectious Substances

Anthrax Virus






Battery Fluid


Miscellaneous Hazardous Materials

Polychlorinated Biphenyls (PCB)


ORM-D (Other Regulated Material-Domestic)

Food Flavorings, Medicines

Combustible Liquids

Fuel Oil

Figure 9.1

A shipping paper describes the hazardous materials being transported. Shipping orders, bills of lading, and manifests are all shipping papers. Figure 9.6 shows an example shipping paper.

After an accident or hazardous materials spill or leak, you may be injured and unable to communicate the hazards of the materials you are transporting. Firefighters and police can prevent or reduce the amount of damage or injury at the scene if they know what hazardous materials are being carried. Your life, and the lives of others, may depend on quickly locating the hazardous materials shipping papers. For that reason the rules require:

  • Shippers to describe hazardous materials correctly and include an emergency response telephone number on shipping papers.
  • Carriers and drivers to quickly identify hazardous materials shipping papers, or keep them on top of other shipping papers and keep the required emergency response information with the shipping papers.
  • Drivers to keep hazardous materials shipping papers:
    • In a pouch on the driver’s door, or
    • In clear view within immediate reach while the seat belt is fastened while driving, or
    • On the driver’s seat when out of the vehicle.

9.3.2 – Package Labels

Shippers put diamond-shaped hazard warning labels on most hazardous materials packages. These labels inform others of the hazard. If the diamond label won’t fit on the package, shippers may put the label on a tag securely attached to the package. For example, compressed gas cylinders that will not hold a label will have tags or decals. Labels look like the examples in Figure 9.2

9.3.3 – Lists of Regulated Products

Placards. Placards are used to warn others of hazardous materials. Placards are signs put on the outside of a vehicle and on bulk packages, which identify the hazard class of the cargo. A placarded vehicle must have at least four identical placards. They are put on the front, rear, and both sides of the vehicle. See Figure 9.3. Placards must be readable from all four directions. They are at least 10 3/4 inches square, square-on-point, in a diamond shape. Cargo tanks and other bulk packaging display the identification number of their contents on placards or orange panels or white square-on-point displays that are the same size as placards.

Identification numbers are a four-digit code used by first responders to identify hazardous materials. An identification number may be used to identify more than one chemical. The letters “NA or “UN” will precede the identification number. The United States Department of Transportation’s Emergency Response Guidebook (ERG) lists the chemicals and the identification numbers assigned to them.

There are three main lists used by shippers, carriers, and drivers when trying to identify hazardous materials. Before transporting a material, look for its name on three lists. Some materials are on all lists, others on only one. Always check the following lists:

  • Section 172.101, the Hazardous Materials Table.
  • Appendix A to Section 172.101, the List of Hazardous Substances and Reportable Quantities.
  • Appendix B to Section 172.101, the List of Marine Pollutants.

The Hazardous Materials Table. Figure 9.4 shows part of the Hazardous Materials Table. Column 1 tells which shipping mode(s) the entry affects and other information concerning the shipping description. The next five columns show each material’s shipping name, hazard class or division, identification number, packaging group, and required labels.

49 CFR 172.101 Hazardous Materials Table


Hazardous Materials Description & Proper Shipping Names

Hazard Class or Division

Identification Numbers


Label Codes

Special Provisions (172.102)

Packaging (173. ***)


Non Bulk













Acetaldehyde ammonia





IB8, IP6




Figure 9.4

Six different symbols may appear in Column 1 of the table.

(+) – Shows the proper shipping name, hazard class, and packing group to use, even if the material doesn’t meet the hazard class definition.

(A) – Means the hazardous material described in Column 2 is subject to the HMR only when offered or intended for transport by air unless it is a hazardous substance or hazardous waste.

(W) – Means the hazardous material described in Column 2 is subject to the HMR only when offered or intended for transportation by water unless it is a hazardous substance, hazardous waste, or marine pollutant.

(D) – Means the proper shipping name is appropriate for describing materials for domestic transportation, but may not be proper for international transportation.

(I) – Identifies a proper shipping name that is used to describe materials in international transportation. A different shipping name may be used when only domestic transportation is involved.

(G) – Means this hazardous material described in Column 2 is a generic shipping name. A generic shipping name must be accompanied by a technical name on the shipping paper. A technical name is a specific chemical that makes the product hazardous

Column 2 lists the proper shipping names and descriptions of regulated materials. Entries are in alphabetical order so you can more quickly find the right entry. The table shows proper shipping names in regular type. The shipping paper must show proper shipping names. Names shown in italics are not proper shipping names.

Column 3 shows a material’s hazard class or division, or the entry “Forbidden.” Never transport a “Forbidden” material. Placard hazardous materials shipments based on the quantity and hazard class. You can decide which placards to use if you know these three things:

  • Material’s hazard class.
  • Amount being shipped.
  • Amount of all hazardous materials of all classes on your vehicle.

Column 4 lists the identification number for each proper shipping name. Identification numbers are preceded by the letters “UN” or “NA.” The letters “NA” are associated with proper shipping names that are only used within the United States and to and from Canada. The identification number must appear on the shipping paper as part of the shipping description and also appear on the package. It also must appear on cargo tanks and other bulk packaging. Police and firefighters use this number to quickly identify the hazardous materials.

Column 5 shows the packing group (in Roman numeral) assigned to a material.

Column 6 shows the hazard warning label(s) shippers must put on packages of hazardous materials. Some products require use of more than one label due to a dual hazard being present.

Column 7 lists the additional (special) provisions that apply to this material. When there is an entry in this column, you must refer to the federal regulations for specific information. The numbers 1-6 in this column mean the hazardous material is a poison inhalation hazard (PIH). PIH materials have special requirements for shipping papers, marking, and placards.

Column 8 is a three-part column showing the section numbers covering the packaging requirements for each hazardous material.

Note: Columns 9 and 10 do not apply to transportation by highway.

Appendix A to 49 CFR 172.101 – The List of Hazardous Substances and Reportable Quantities. The DOT and the EPA want to know about spills of hazardous substances. They are named in the List of Hazardous Substances and Reportable Quantities. See Figure 9.5. Column 3 of the list shows each product’s reportable quantity (RQ). When these materials are being transported in a reportable quantity or greater in one package, the shipper displays the letters RQ on the shipping paper and package. The letters RQ may appear before or after the basic description. You or your employer must report any spill of these materials, which occurs in a reportable quantity.

Appendix A to 49 CFR 172

List of Hazardous Substances and Reportable Quantities

Hazardous Substances

Reportable Quantity (RQ) Pounds (Kilograms)

Phenyl mercaptan @

100 (45.4)

Phenylmercury acetate

100 (45.4)


100 (45.4)


10 (4.54)


10 (4.54)


100 (45.4) *

Phosphoric acid

5,000 (2270)

Phosphoric acid, diethyl

4-nitrophenyl ester

100 (45.4)

Phosphoric acid, lead salt

10 (.454)

Figure 9.5

If the words INHALATION HAZARD appear on the shipping paper or package, the rules require display of the POISON INHALATION HAZARD or POISON GAS placards, as appropriate. These placards must be used in addition to other placards, which may be required by the product’s hazard class. Always display the hazard class placard and the POISON INHALATION HAZARD placard, even for small amounts.

Appendix B to 49 CFR 172.101 – List of Marine Pollutants. Appendix B is a listing of chemicals that are toxic to marine life. For highway transportation, this list is only used for chemicals in a container with a capacity of 119 gallons or more without a placard or label as specified by the HMR.

Any bulk packages of a Marine Pollutant must display the Marine Pollutant marking (white triangle with a fish and an “X” through the fish). This marking (it is not a placard) must also be displayed on the outside of the vehicle. In addition, a notation must be made on the shipping papers near the description of the material: “Marine Pollutant.”

9.3.4 – The Shipping Paper

The shipping paper shown in Figure 9.6 describes a shipment. A shipping paper for hazardous materials must include:

  • Page numbers if the shipping paper has more than one page. The first page must tell the total number of pages. For example, “Page 1 of 4.”
  • A proper shipping description for each hazardous material.
  • A shipper’s certification, signed by the shipper, saying they prepared the shipment according to the regulations.

9.3.5 – The Item Description

If a shipping paper describes both hazardous and non-hazardous products, the hazardous materials will be either:

  • Entered first.
  • Highlighted in a contrasting color.
  • Identified by an “X” placed before the shipping description (ID#, Shipping Name, Hazard Class, Packing Group) in a column captioned “HM.” The letters “RQ” may be used instead of “X” if a reportable quantity is present in one package.

The basic description of hazardous materials includes the identification number, proper shipping name, hazard class or division, and the packing group, if any, in that order. The packing group is displayed in Roman numerals and may be preceded by “PG.”

Shipping name, hazard class, and identification number must not be abbreviated unless specifically authorized in the hazardous materials regulations. The description must also show:

  • The total quantity and unit of measure.
  • The letters RQ, if a reportable quantity.
  • If the letters RQ appear, the name of the hazardous substance (if not included in the shipping name).
  • The number and type of packages (example: “6 Drums”)
  • For all materials with the letter “G” (Generic) in Column 1, the technical name of the hazardous material.

Shipping papers also must list an emergency response telephone number. The emergency response telephone number is the responsibility of the shipper. It can be used by emergency responders to obtain information about any hazardous materials involved in a spill or fire. The telephone number must be:

  • The number of the person offering the hazardous material for transportation (if the shipper/offer is the emergency response information (ERI) provider); or
  • The number of an agency or organization capable of, and accepting responsibility for, providing the detailed information. The person who is registered with the ERI provider must be identified by name, or contract number or other unique identified assigned by the ERI provider, on the shipping paper.

Shippers also must provide emergency response information to the motor carrier for each hazardous material being shipped. The emergency response information must be able to be used away from the motor vehicle and must provide information on how to safely handle incidents involving the material. It must include information on the shipping name of the hazardous materials, risks to health, fire, explosion, and initial methods of handling spills, fires, and leaks of the materials.

Such information can be on the shipping paper or some other document that includes the basic description and technical name of the hazardous material. Or, it may be in a guidance book such as the Emergency Response Guidebook (ERG). Motor carriers may assist shippers by keeping an ERG on each vehicle carrying hazardous materials. The driver must provide the emergency response information to any federal, state, or local authority responding to a hazardous materials incident or investigating one.

Total quantity and number & type of packages must appear before or after the basic description. The packaging type and the unit of measurement may be abbreviated. For example:

  • 10 ctns. UN1263, Paint, 3, PG ll, 500 lbs.

The shipper of hazardous wastes must put the word WASTE before the proper shipping name of the material on the shipping paper (hazardous waste manifest). For example:

  • UN1090, Waste Acetone, 3, PG ll.

A non-hazardous material may not be described by using a hazard class or an identification number. Shippers must keep a copy of shipping papers (or an electronic image) for a period of 2 years (3 years for hazardous waste) after the material is accepted by the initial carrier.

If one provides a carrier service only and is not the originator of the shipment, a carrier is required to keep a copy of the shipping paper (or electronic image) for a period of 1 year.

9.3.6 – Shipper’s Certification

When the shipper packages hazardous materials, he/she certifies that the package has been prepared according to the rules. The signed shipper’s certification appears on the original shipping paper. The only exceptions are when a shipper is a private carrier transporting their own product and when the package is provided by the carrier (for example, a cargo tank). Unless a package is clearly unsafe or does not comply with the HMR, you may accept the shipper’s certification concerning proper packaging. Some carriers have additional rules about transporting hazardous materials. Follow your employer’s rules when accepting shipments.

9.3.7 – Package Markings and Labels

Shippers print required markings directly on the package, an attached label, or tag. An important package marking is the name of the hazardous material. It is the same name as the one on the shipping paper. The requirements for marking vary by package size and material being transported. When required, the shipper will put the following on the package:

  • The name and address of shipper or consignee.
  • The hazardous material’s shipping name and identification number.
  • The labels required.

It is a good idea to compare the shipping paper to the markings and labels. Always make sure that the shipper shows the correct basic description on the shipping paper, and verifies that the proper labels are shown on the packages. If you are not familiar with the material, ask the shipper to contact your office.

If rules require it, the shipper will put RQ, MARINE POLLUTANT, BIOHAZARD, HOT, or INHALATION-HAZARD on the package. Packages with liquid containers inside will also have package orientation markings with the arrows pointing in the correct upright direction. The labels used always reflect the hazard class of the product. If a package needs more than one label, the labels must be close together, near the proper shipping name.

9.3.8 – Recognizing Hazardous

Learn to recognize shipments of hazardous materials. To find out if the shipment includes hazardous materials, look at the shipping paper. Does it have:

  • An entry with a proper shipping name, hazard class, and identification number?
  • A highlighted entry, or one with an X or RQ in the hazardous materials column?

Other clues suggesting hazardous materials:

  • What business is the shipper in? Paint dealer? Chemical supply? Scientific supply house? Pest control or agricultural supplier? Explosives, munitions, or fireworks dealer?
  • Are there tanks with diamond labels or placards on the premises?
  • What type of package is being shipped? Cylinders and drums are often used for hazardous materials shipments.
  • Is a hazard class label, proper shipping name, or identification number on the package?
  • Are there any handling precautions?

(IMPORTANT NOTE: To view complete regulatory requirements for the transportation of hazardous materials one should refer to the Code of Federal Regulations, Title 49, Parts 100-185.)

9.3.9 – Hazardous Waste Manifest

When transporting hazardous wastes, you must sign by hand and carry a Uniform Hazardous Waste Manifest. The name and EPA registration number of the shippers, carriers, and destination must appear on the manifest. Shippers must prepare, date, and sign by hand the manifest. Treat the manifest as a shipping paper when transporting the waste. Only give the waste shipment to another registered carrier or disposal/treatment facility. Each carrier transporting the shipment must sign by hand the manifest. After you deliver the shipment, keep your copy of the manifest. Each copy must have all needed signatures and dates, including those of the person to whom you delivered the waste.

9.3.10 – Placarding

Attach the appropriate placards to the vehicle before you drive it. You are only allowed to move an improperly placarded vehicle during an emergency, in order to protect life or property.

Placards must appear on both sides and both ends of the vehicle. Each placard must be:

  • Easily seen from the direction it faces.
  • Placed so the words or numbers are level and read from left to right.
  • At least three inches away from any other markings.
  • Kept clear of attachments or devices such as ladders, doors, and tarpaulins.
  • Kept clean and undamaged so that the color, format, and message are easily seen.
  • Be affixed to a background of contrasting color.
  • The use of “Drive Safely” and other slogans is prohibited.
  • The front placard may be on the front of the tractor or the front of the trailer.

To decide which placards to use, you need to know:

  • The hazard class of the materials.
  • The amount of hazardous materials shipped.
  • The total weight of all classes of hazardous materials in your vehicle.

9.3.11 – Placard Tables

There are two placard tables, Table 1 and Table 2. Table 1 materials must be placarded whenever any amount is transported. See Figure 9.7.

Placard Table 1
Any Amount

If your vehicle contains any amount of……

Placard as…

1.1 Mass Explosives

Explosives 1.1

1.2 Project Hazards

Explosives 1.2

1.3 Mass Fire Hazards

Explosives 1.3

2.3 Poisonous/Toxic Gases

Poison Gas

4.3 Dangerous When Wet

Dangerous When Wet

5.2 (Organic Peroxide, Type B, liquid or solid,
Temperature controlled)

Organic Peroxide

6.1 (Inhalation hazard zone A & B only)

Poison/toxic inhalation

7 (Radioactive Yellow III label only)


Figure 9.7

Except for bulk packaging, the hazard classes in Table 2 need placards only if the total amount transported is 1,001 pounds or more including the package. Add the amounts from all shipping papers for all the Table 2 products you have on board. See Figure 9.8.

Placard Table 2
1,001 Pounds Or More

Category of Material (Hazard class or division number and additional description, as appropriate)

Placard Name

1.4 Minor Explosion

Explosives 1.4

1.5 Very Insensitive

Explosives 1.5

1.6 Extremely Insensitive

Explosives 1.6

2.1 Flammable Gases

Flammable Gas

2.2 Non- Flammable Gases

Non-Flammable Gas.

3 Flammable Liquids


Combustible Liquid


4.1 Flammable Solids

Flammable Solid

4.2 Spontaneously Combustible

Spontaneously Combustible

5.1 Oxidizers


5.2 (other than organic peroxide, Type B, liquid or solid, Temperature Controlled)

Organic Peroxide

6.1 (other than inhalation hazard zone A or B)


6.2 Infectious Substances


8 Corrosives


9 Miscellaneous Hazardous Materials

Class 9**



Figure 9.8

Placards used to identify the primary or subsidiary hazard class of a material must have the hazard class or division number displayed in the lower corner of the placard. Permanently affixed subsidiary hazard placards without the hazard class number may be used as long as they stay within color specifications.

Placards may be displayed for hazardous materials even if not required so long as the placard identifies the hazard of the material being transported.

Bulk packaging is a single container with a capacity of 119 gallons or more. A bulk package, and a vehicle transporting a bulk package, must be placarded, even if it only has the residue of a hazardous material. Certain bulk packages only have to be placarded on the two opposite sides or may display labels. All other bulk packages must be placarded on all four sides.

Test Your Knowledge

  • Shippers package in order to (fill in the blank) the material.
  • Driver placard their vehicle to (fill in the blank) the risk.
  • What three things do you need to know to decide which placards (if any) you need?
  • A hazardous materials identification number must appear on the (fill in the blank) and on the (fill in the blank). The identification number must also appear on cargo tanks and other bulk packaging.
  • Where must you keep shipping papers describing hazardous materials?

These questions may be on your test. If you can’t answer them all, re-read subsections 9.1, 9.2 and 9.3.