The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) provides a globally consistent approach to communicating chemical hazards. The standard GHS pictogram is a square set on a point, giving it the appearance of a diamond. This diamond features a distinctive red border, a white background, and a contrasting black symbol in the center. The red diamond instantly communicates a degree of hazard to anyone who encounters it.
The Purpose of GHS Pictograms
These standardized symbols function as a universal language for chemical safety, ensuring that hazard information is communicated clearly and consistently across different countries and languages. The United Nations developed the system to streamline numerous national and regional hazard communication systems into one cohesive framework. This global standardization is particularly useful for international trade, allowing chemicals to be shipped and handled safely worldwide. Ultimately, the pictograms serve to enhance workplace safety by providing quick, visual warnings about the potential dangers of a substance.
Anatomy of a GHS Pictogram
The physical design of the GHS pictogram is specified to maximize visibility and clarity. The “diamond” shape, a square rotated 45 degrees, is defined by a thick, solid red frame. This red border is a regulated component of the GHS standard, acting as the primary identifier that a significant hazard is present. Inside this red boundary, the background is stark white, providing high contrast against the black hazard symbol. The black graphic placed centrally represents the specific type of danger, such as a flame or a skull and crossbones.
Understanding the Nine Hazard Categories
The GHS system utilizes nine distinct pictograms to communicate a wide range of physical, health, and environmental hazards.
- The Exploding Bomb represents explosive substances, including unstable chemicals and self-reactive materials that pose a risk of fire, blast, or projection.
- The Flame pictogram is used for flammable materials, such as gases, liquids, and solids that can easily ignite, or pyrophoric substances that self-ignite upon contact with air.
- Oxidizers are identified by the Flame Over Circle symbol, indicating chemicals that can cause or intensify a fire by yielding oxygen.
- The Gas Cylinder pictogram identifies gases under pressure, including compressed, liquefied, or dissolved gases, posing a physical hazard.
- Corrosive substances, which can cause severe skin burns, eye damage, or be corrosive to metals, are marked with the Corrosion symbol.
- Acute toxicity, indicating a substance is fatal or highly toxic if swallowed, inhaled, or absorbed through the skin, is represented by the Skull and Crossbones symbol.
- The Exclamation Mark pictogram marks substances with lower-level toxicity or irritation, covering hazards like skin or eye irritation and respiratory tract irritation.
- The Health Hazard symbol is reserved for the most serious chronic health dangers, such as carcinogens, mutagens, reproductive toxicants, and respiratory sensitizers.
- The Environment pictogram, a tree and fish, indicates a substance hazardous to aquatic life and ecosystems, though this symbol is not mandatory in all jurisdictions.