Study guide
CDL hazmat: placards, shipping papers, distances
Hazmat rules are about telling people what you carry. Learn when a load needs placards, what the shipping paper says and the distances the rules set.
- Who takes it
- Anyone who wants the hazardous materials endorsement. A TSA background check is required as well.
- To pass
- 80 percent.
- Questions
- 30 in Michigan and Pennsylvania. Check your state's manual.
- What it covers
- Placards, shipping papers, loading, parking, driving and emergencies.
On this page
The nine hazard classes
A material's class names its risk. The number is on the label, the placard and the shipping paper. Manual 9.3
- Class 1
- Explosives. Divisions 1.1, 1.2 and 1.3 carry the strictest rules for parking, routes and loading.
- Class 2
- Gases: flammable (2.1), non-flammable (2.2) and poisonous (2.3).
- Class 3
- Flammable liquids.
- Class 4
- Flammable solids (4.1), spontaneously combustible materials (4.2) and materials that are dangerous when wet (4.3).
- Class 5
- Oxidizers (5.1) and organic peroxides (5.2).
- Class 6
- Poisons (6.1) and infectious substances (6.2).
- Class 7
- Radioactive materials.
- Class 8
- Corrosives.
- Class 9
- Miscellaneous hazardous materials.
Worked example: does this load need placards?
Two tables decide. Table 1 materials are placarded in any amount. As a general rule, Table 2 materials that are not in bulk packaging need placards once they total 1,001 pounds, packages included: add up the Table 2 products on all your shipping papers. The rule has exceptions. Class 9 needs no placard in transport within the United States. And a material marked INHALATION HAZARD, or one with a subsidiary hazard of dangerous when wet, needs that placard at any weight. Manual 9.3
600 pounds of a flammable liquid in drums (Class 3, Table 2). Nothing else on board.
No placards. The Table 2 total is under 1,001 pounds.
The same 600 pounds, plus 500 pounds of a corrosive in drums (Class 8, Table 2).
Placards. 600 and 500 make 1,100 pounds. Use FLAMMABLE and CORROSIVE placards, or DANGEROUS placards in place of both.
50 pounds of a material that is dangerous when wet (Division 4.3, Table 1).
Placards. Table 1 materials are placarded whenever any amount is transported.
Table 1: placards in any amount
The federal placard table lists these. Everything else that needs a placard is in Table 2.
- 1.1, 1.2, 1.3
- Explosives of these three divisions.
- 2.3
- Poison gas.
- 4.3
- Dangerous when wet.
- 5.2
- Organic peroxide, Type B, liquid or solid, temperature controlled.
- 6.1
- Poison inhalation hazard only. Other poisons are in Table 2.
- 7
- Radioactive, Yellow III label only.
The shipping paper description, in its fixed order
The papers ride in one of three places: a pouch on the driver's door, in clear view within reach while you are belted in, or on the driver's seat when you are out of the cab. The basic description on them always runs in this order. Manual 9.3
Identification number
Four digits after the letters UN or NA. Responders look the number up in the Emergency Response Guidebook.
Proper shipping name
As Column 2 of the Hazardous Materials Table prints it. Names in italics are not proper shipping names.
Hazard class or division
From Column 3 of the table. If Column 3 says Forbidden, never transport the material.
Packing group
In Roman numerals, sometimes after the letters PG. Not every material has one.
The distances and limits
- 25 feet
- No smoking within this distance of a placarded cargo tank used for Class 3 or Division 2.1, or of any vehicle carrying Class 1, Class 3, Division 4.1, Division 4.2 or Class 5. Manual 9.6
- 100 feet
- The person attending a placarded vehicle is in it, awake and not in the sleeper berth, or within 100 feet with the vehicle in clear view. Manual 9.6
- 300 feet
- With Division 1.1, 1.2 or 1.3 explosives, do not park this close to a bridge, tunnel, building, place where people gather or open fire, except briefly for something like fueling. Never within 5 feet of the traveled part of the road. Manual 9.6
- 15 to 50 feet
- Where to stop before the nearest rail when you are placarded, carry any amount of chlorine, or have a cargo tank used for hazardous materials, loaded or empty. Manual 9.6
- 50
- The highest total transport index of radioactive packages allowed in one vehicle. Manual 9.4
- 10 B:C
- The least UL rating of the fire extinguisher on the power unit of a placarded vehicle. Manual 9.6
Five common mistakes
Common answerUnder 1,001 pounds, no load needs placards.
The manual 9.3Table 1 materials need them in any amount. So does anything marked INHALATION HAZARD, and so does a material whose subsidiary hazard is dangerous when wet.
Common answerWith two Table 2 classes on board I must use DANGEROUS placards.
The manual 9.3You may. It is an option, not a requirement. And a class of which you loaded 2,205 pounds or more at one place needs its own placard.
Common answerIf something leaks, I can follow the smell to find it.
The manual 9.7Never use smell. Toxic gases can destroy your sense of smell, and some injure or kill without any odor. Identify the material from the shipping papers, the labels or where the package sits.
Common answerIf the load is leaking, drive on to the next truck stop and call from there.
The manual 9.7Park, secure the area, stay with the vehicle and send for help. Do not move it more than safety requires.
Common answerA look at the tires is enough.
The manual 9.6Examine every tire at the start of each trip and each time you park. A tire pressure gauge is the only acceptable way to check pressure.
Three practice questions
Pick an answer. The reason and the manual's own sentence follow.
You load 400 pounds of one Table 2 material in boxes and 700 pounds of another Table 2 material in drums. The weights include the packages. Do you need placards?
Show the answer
The answer is B. The 1,001 pounds is the total of all Table 2 materials on the vehicle, packages included. 400 and 700 make 1,100 pounds.
Commercial driver manual, section 9.3Except 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.
You are attending a placarded vehicle parked on the shoulder of a road. Where may you be?
Show the answer
The answer is B. Attending means you could act at once: awake and out of the sleeper berth, or close enough to see the vehicle and reach it.
Commercial driver manual, section 9.6Be in the vehicle, awake, and not in the sleeper berth, or within 100 feet of the vehicle and have it within clear view.
In what order does the basic description of a hazardous material appear on a shipping paper?
Show the answer
The answer is B. The number comes first because it is what responders look up. The name, the class and the packing group follow, always in that order.
Commercial driver manual, section 9.3The 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.
Sources
- Oregon Commercial Driver Manual, section 9: Hazardous MaterialsThe edition this page is checked against. It carries the national model text that state manuals share.
- 49 CFR 172.504: the placard tables and their exceptions
- 49 CFR 172.505: placards for subsidiary hazards
- 49 CFR 173.2: hazard classes and divisions
- 49 CFR 383.135: the passing score of 80 percent
- Michigan Commercial Driver License Manual: number of questions
- PennDOT Commercial Driver's License Fact Sheet: number of questions
Reviewed by CDL Greenlight on October 13, 2026. CDL Greenlight writes and checks this page. Every figure is the one the commercial driver manual prints, with its section named beside it. Where your state has a rule of its own, your state's manual decides.
Found a mistake? Write to support@cdlgreenlight.com. Corrections we have published