Federal law requires that any household product containing hazardous substances must be labeled accordingly. They are rated through a system of the following four words: POISON - DANGER - WARNING - CAUTION

POISON: Indicates the highest hazard level of the group, and means that a product is highly toxic, and can cause injury or death if ingested, inhaled, or absorbed by the skin.

DANGER: Means that a product is either highly toxic, flammable or corrosive.

WARNING OR CAUTION: Both indicate that a product is toxic, corrosive, reactive or flammable.