Class 6 poison / infectious substances

Black and white skull and crossbones placard meaning cdl

A skull and crossbones on a white placard means poison. It is used for Division 6.1 (poison solids and liquids) with a 6, and for Division 2.3 (toxic gas) with a 2. The symbol is black on white. Read the class number at the bottom to tell whether it is a poison (6) or a poison gas (2).

Black and white skull and crossbones placard meaning cdl · CDL Placards Hazmat placard practice

The skull means poison

The skull and crossbones is the universal warning for a poisonous material, and on a hazard placard it appears as a black skull on a white background. It tells you the material can poison you, whether by swallowing, absorption, or breathing, which is why it is reserved for the most directly toxic substances.

Two classes share the skull

The same skull appears on two placards. Division 6.1 is poison, for toxic solids and liquids, with a 6 at the bottom point. Division 2.3 is toxic gas, with a 2. Both warn about poisoning; the difference is the physical state of the material, shown by the class number.

Reading the skull placard

The number is the tell:

Poison 6.1Toxic gas 2.3
BackgroundWhiteWhite
SymbolSkull and crossbonesSkull and crossbones
Number62
StateSolid or liquidGas

Same skull; the number tells you poison (6) or poison gas (2). Confirm in your official manual.

Do not confuse it with Class 8

Some people mix the skull placard up with the black-and-white Class 8 corrosive, but they are different. The skull is on a white background and warns of poisoning. Class 8 is split white-over-black and shows a liquid corroding a hand and metal, warning of chemical burns. Different symbol, different danger.

How to study it

Train your eye to drop to the number whenever you see a white skull placard: a 6 means a poison solid or liquid, a 2 means a toxic gas. Drill the pair together since that is where confusion happens. As always, confirm the exact details and any edge cases in your official state CDL manual.

Frequently asked questions

What does a skull and crossbones placard mean?
It means a poisonous material. A skull on white with a 6 is poison (Division 6.1, solid or liquid); with a 2 it is toxic gas (Division 2.3). Read the number to tell them apart. Confirm in your official manual.
Is the skull placard the same as corrosive?
No. The skull on white warns of poisoning. Class 8 corrosive is split white-over-black with a symbol of liquid burning a hand and metal. Different symbol and different hazard.
What is the difference between poison and toxic gas?
Both use the skull on white. Poison 6.1 is a solid or liquid (number 6); toxic gas 2.3 is a gas (number 2). The class number is the difference.

Practice this before test day

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