Graphology - the study of handwritings; autograph - written with one's own hand; seismograph - a machine noting strength and duration of earthquakes. marina - a harbor for pleasure boats; maritime - relating to the sea; submarine - an undersea boat; aquamarine - color of sea water.
Chemicals are classified into various hazard classifications in accordance with their physiochemical properties and health hazards. Each class of chemical has a pictorial symbol called a danger symbol.
GHS describes the nature and severity of a chemical hazard by hazard class and hazard category: 1  GHS hazard class represents the nature of a chemical hazard, i.e., flammable liquids, carcinogen. 2  GHS hazard category is the division of criteria within each hazard class. For example, hazard class flammable liquids can be divided into 4 categories among which flammable liquids category 1 represents the most severe hazard.