Physical hazard classification of mixtures

Once you have identified all of the component substances in a mixture, the physical hazards can be derived from:

• the physical properties of the component substances and
• any new physical hazards which have been created by mixing incompatible materials together

The document on screening physical hazards of mixtures will enable you to identify which physical hazards require testing: Screening questions for physical hazards of mixtures v1.3 03-02-2018.

There are several scenarios where testing for physical hazards of mixtures may not be required:

• flammability of gaseous mixtures and oxidising potential of gaseous mixtures, where the calculation method ISO 10156:2010 should be used.  This standard can be purchased from the BSI at http://shop.bsigroup.com/ProductDetail/?pid=000000000030232773 .
• flash point of flammable liquids, although this can be more costly than simply carrying out a flash point test, see https://ttenvironmenta.wpengine.com/clp-knowledgebase/flammability-of-liquid-mixtures-calculation/ .
• organic peroxide classification, which can be calculated using the method given in the physical hazards screening document at: Screening questions for substance physical hazards v1.2

Once you have finalised the list of physical hazards of your mixture which require testing, the tests should be carried out either in-house, if you have the equipment and personnel to provide good quality data, or at an external lab.  The test results should then be classified from first principles, see https://ttenvironmenta.wpengine.com/clp-knowledgebase/clp-classification-from-first-principles/ .