Safety hazard symbols serve as warnings to the unwary. Thoughtful concern for the welfare of others has prompted the development of these symbols. Astute minds have endeavoured to devise symbols that are readily understood, and the standardisation of these symbols has meant immediate comprehension by people of different nationalities. Because many hazards are present in the world, many different of hazard symbols exist.
Advantage of Symbols
An effectively worded warning conveys precise information concerning hazards. If the word "poison" appears on a bottle, most people know what it means. However, not everyone understands English. A French speaker might even mistake it for "poisson," the French word for fish. And some people cannot read and write. A universally understood symbol solves the problem. When a skull with two crossed bones appears on a bottle, the symbol effectively conveys the information that the contents of the bottle are poisonous.
Globally Harmonized System
Different countries have developed their own safety hazard symbols for chemicals. However, the United Nations has been promoting a globally harmonised system, or GHS, of hazardous chemical labelling, including standardised symbols. GHS attempts to give an exact description of hazards. For example, GHS still uses the skull and crossbones for poisons that are fatal or dangerously toxic when swallowed, inhaled or applied to the skin, but it uses an exclamation mark if the poison is less dangerous. Such agencies as the U.S. Environmental Protection Agency are wrestling with the problem of changing their own established systems of symbols to conform to GHS.
Chemical Hazard Symbols
Some chemicals can burst into flames, cause corrosion on contact, or react explosively when exposed to heat, water or air. Various symbols issue an appropriate warning. For example, in the United States, a red diamond with a picture of a flame and the word "FLAMMABLE" delivers a self-explanatory message. In the United Kingdom, a black and white flame on a square orange background issues the same warning. Also in the United Kingdom, the picture of a black, dead tree and a black, dead fish show that a chemical is dangerous to the environment. GHS uses the same symbol, but instead of the orange UK background, it has a white diamond-shaped background with a thin red border.
Road Hazard Symbols
Traffic hazard symbols alert motorists to phenomena that might cause accidents. In the United States, road hazard symbols are fairly uniform from state to state. A picture of a deer on a diamond-shape yellow sign warns motorists to watch for deer. A red octagonal sign warns drivers to stop. If a symbol pictures a pair of children, a school zone is at hand. Other symbols mark the presence of a sharp curve, a steep hill or construction work.
Other Interesting Symbols
A jagged lightning-like symbol warns of high voltage. Foods treated with radiation must display a radura, a picture of a green plant inside a nearly continuous green circle. The U.S. Occupational Safety and Healthy Administration has fabricated some interesting triangular hazard symbols, such as ice cracking under a man's weight to indicate thin ice.