Canadian Centre for Occupational Health and Safety
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GHS Classification of Mixtures: An Introduction
Presenter:  CCOHS
Availability:  On demand – Watch it now

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Product Description

Understand how mixtures are classified according to the Globally Harmonized System of Chemical Classification and Labelling (GHS), and get guidance on how to assign GHS classifications to products.

This webinar describes the tiered approach to classifying mixtures for the GHS as outlined in the “purple book”*. You will learn when it is appropriate to classify using data for the complete mixture, what the bridging principles are and when they can be used, and the different methods that can be used to estimate hazards based on ingredient information. The discussion will provide guidance on classifying mixtures according to the GHS. Examples will be provided.

Topics include:

  • Tiered Approach to Classifying Mixtures
    • Data available for complete mixture
    • Bridging principles
      • Dilution
      • Batching
      • Concentration of mixtures of the highest category
      • Interpolation within one category
      • Substantially similar mixtures
      • Aerosols
    • Estimation of Hazards
      • Cut-off values/concentration limits
      • Summation (additivity)
      • Proportionality (additivity formula)
  • Additional considerations
  • Resources

*Globally Harmonized System of Classification and Labelling of Chemicals (GHS), United Nations

You may also be interested in the other webinars in our series on GHS classification and labelling:

Target Audience

This webinar is intended for individuals who are charged with classifying mixtures according to GHS.

Length: 47 minutes

This webinar was recorded in December 2013.

For a PDF copy of the presentation slides, please contact

System Requirements

You must have Windows Media 9.0 or higher to view the recorded webinar. You do not need a microphone or a telephone to listen to this webinar - just listen to the presentation through your computer's speakers or headphones.

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