Summary of CLP classification from first principles

CLP classification from first principles is based on obtaining data from published sources, or by testing, and working through the various classification methods in the CLP regulation.  There are several types of test used:

• physical properties of a substance or mixture, and calculating the hazards from the results
• direct measurement of physical hazards
• health hazards inferred from in physical or chemical properties, or using vitro animal testing
• health hazards inferred from live animal tests
• environmental hazards on vertebrate animals (fish)
• environmental hazards on invertebrate animals, insects or plants

CLP classification for physical hazards is the most common type of first-principles classification carried out in industry, as mixtures often require this testing.

Health and environmental hazards are usually classified when a substance goes through REACH registration, and it is usually carried out by the Lead Registrant, or their consultants.  However, it may also be required for novel substances, or mixtures which have been, or need to be tested.