A warning label is a label attached to a product, or contained in a product's instruction manual, warning the user about risks associated with its use, and may include restrictions by the manufacturer or seller on certain uses. Most of them are placed to limit civil liability in lawsuits against the item's manufacturer or seller (see product liability). That sometimes results in labels which for some people seem to state the obvious. Lack of a warning label can become an informational defect, which is a type of product defect.

Government regulation

In the United States, warning labels have been instituted under a number of different government organizations. For instance, the Federal Food, Drug, and Cosmetic Act of 1938. Cigarettes were not required to have warning labels in the United States until Congress passed the Federal Cigarette Labeling and Advertising Act (FCLAA) in 1965. Other organizations that create label standards in the U.S.—the Occupational Safety and Health Administration (OSHA) and American National Standards Institute (ANSI)—govern their use. The U.S. organizations pull from international organizations such as the Globally Harmonized System of Classification and Labelling of Chemicals and the International Standards Organization. In the EEA, a product containing hazardous mixtures must have a Unique formula identifier (UFI) code. This is not a warning label per se, but a code that helps poison control centres identify the exact formula of a hazardous product.

Hazard level warning labels

In the US or elsewhere: The terms Danger, Warning and Caution are regulated by the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) ANSI Z535. Graphic symbols are regulated by ISO 7010.

Abnormal warning labels

Some companies hold competitions to find particularly strange warning labels, such as Michigan Lawsuit Abuse Watch's "Wacky Warning Labels" contest. The 2004 winner was "If you do not understand, or cannot read, all directions, cautions and warnings, do not use this product." While many safe products intended for human consumption may require warning labels due to the health risks associated with using them, it is only tobacco products that have strongly worded warnings on their health risks.