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Placarding Requirements and Placement

Placards are the diamond-shaped signs that warn everyone around your vehicle about the hazard class of your cargo. This chapter explains when placards are required, how they must be placed and maintained, and how to read the color, symbol, and number on each one. Correct placarding is both a legal requirement and a critical safety communication.

Purpose and Appearance of Placards

Placards communicate the hazard class of the cargo to other drivers, the public, and emergency responders. They are standardized in shape, color, and symbol so they can be recognized instantly. Understanding what a placard shows helps everyone respond correctly to the hazard.

Diamond shape

Placards are squares displayed on a point so they appear as a diamond.

Class number

The number at the bottom shows the hazard class or division, such as 3 for flammable liquid.

Color and symbol

Standardized colors and symbols indicate the hazard, such as red with a flame for flammables.

Identification number

Bulk packagings and cargo tanks may display the four-digit ID number on or next to the placard.

When Placards Are Required

Two placard tables determine when placards are needed. Table 1 materials always require placards, while Table 2 materials require them only above a weight threshold. Knowing which table applies tells you when your vehicle must be placarded.

Table 1 materials

The most dangerous materials must be placarded for any amount, no matter how small.

Table 2 threshold

Placards are required when 1,001 pounds or more combined of Table 2 materials are aboard.

DANGEROUS placard

May be used for mixed Table 2 loads of different classes totaling 1,001 pounds or more.

Endorsement link

The hazmat endorsement is generally required whenever a load must be placarded.

Placement on the Vehicle

Placards must be visible from every direction and positioned so they read correctly. They must be kept clean, undamaged, and separated from other markings. Proper placement ensures the hazard is clear no matter which side of the vehicle is approached.

All four sides

Display placards on the front, rear, and both sides of the vehicle.

Readable orientation

Turn placards so words and numbers are level and read left to right, points up and down.

3-inch clearance

Keep placards at least 3 inches from other markings that could reduce their effectiveness.

Match the cargo

Ensure placards correspond to the hazardous materials listed on the shipping papers.

Maintaining Placards During Transport

Placards must stay in place and legible from loading until the material is unloaded and the container is cleaned or purged. Drivers must replace lost, torn, or dirty placards as soon as it is safe. Well-maintained placards keep the hazard communicated throughout the trip.

Keep until cleaned

Placards remain from loading until the material is unloaded and the container is cleaned, purged, or reloaded safely.

Replace damaged placards

Replace or clean lost, torn, faded, or dirty placards as soon as it is safe.

Durable material

Placards must be weather-resistant and keep their color and readability throughout transport.

Empty but uncleaned

An emptied but uncleaned tank may still require placards until it is purged.

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Safe Loading, Unloading, and Segregation

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Last updated: July 2026