GHS is the global system for the classification and labelling of dangerous substances. Dangerous substances are subdivided into twenty-nine hazard classes.
These twenty-nine hazard classes are subdivided as follows:
16 classes for physical hazards;
10 classes for health hazards;
3 classes for environmental hazards.
Nine pictograms are available for indicating these different hazard classes.
The hazard classes are further subdivided into sub-hazard categories 1, 2, 3 or 4.
Sub-hazard category 1 is the most dangerous.
The classification category also contains a signal word.
The signal words are: hazard or warning.
The 9 available pictograms with the description and explanation are shown below.
Substances and preparations which may explode (very fast combustion) even without the participation of oxygen are marked with this symbol.
For example, flammable liquids are divided into three categories:
Category 1 extremely flammable (signal word 'danger’)
Liquids with a flashpoint < 23°C and initial boiling point <= 35°C
Category 2 highly flammable (signal word 'danger’)
Liquids with a flashpoint < 23°C and initial boiling point > 35°C
Category 3 flammable (signal word 'warning’)
Liquids with a flashpoint ≥ 23°C and ≤ 60°C. This category also includes gas oil, diesel and light fuel oil with a flashpoint range between ≥ 55°C and ≤ 75°C.
These are substances and mixtures which, in contact with other substances and/or mixtures (especially flammable substances), can cause or contribute to fire.
This group comprises compressed gases, liquefied gases, refrigerated liquefied gases and dissolved gases.
This group includes all substances that are corrosive to metals and the skin, as well as substances that can cause serious eye damage.
Substances and mixtures which, even in low quantities, may cause harm or death within a few hours or a day if inhaled or absorbed via the mouth or skin.
Substances and mixtures which, in direct prolonged or repeated contact with the skin or mucous membranes, can cause inflammation. This group also comprises narcotic and skin-sensitising substances. These are substances which, absorbed through the skin, may give rise to such a reaction of hypersensitisation (hypersensitivity) that subsequent exposure to the substance or preparation will cause characteristic adverse effects.
This includes carcinogenic, mutagenic and reprotoxic (CMR) substances which may cause cancer, give rise to hereditary genetic disorders or have an effect on the fertility of men and/or women or which harm the unborn child (signal word Danger) or which are suspected of having such effects (signal word Warning).
This group also includes respiratory sensitisers, substances with aspiration hazard and substances with specific target organ toxicity (STOT).