The UN GHS regulations are a great step forward in providing a universal system for assessing and communicating hazards of substances and mixtures, but it does not provide perfect harmonization for several reasons, including:
- Differing implementations of the GHS regulation
- Implementations of different revisions of the GHS standards
- County-specific additions of hazard categories not included in the GHS regulation
- Inconsistent assessments of substance hazards by different countries
The UN GHS regulation uses what is known as a “building-block” approach. That is, it provides a framework, but individual countries are free to choose which aspects of the regulation meets their specific regulatory requirements. So, this means that the EU chose to not include Acute Toxicity, category 5, Flammable liquids, category 4, and a few other hazard categories. Likewise, the US HCS regulation does not include the same CLP categories plus also excludes all Aquatic Hazards (because those are the purview of the US EPA, not OSHA). Consequently, this leads to slightly differing classifications depending on which GHS implementation you are using (called “GHS Flavors” in ProductVision).
Also important is which revision of the UN GHS Purple Book that the specific country is using. In the case of EU CLP, it started with Revision 3, but has now been adjusted to include changes in later UN GHS revisions. In the US, the US HCS 2012 standard is based upon Revision 3, but it has remained frozen at this level, even though the regulation claims to be a “living-standard” which will be updated periodically as the UN GHS is updated (we will see). Other countries implemented the UN GHS standards directly and “float” with the current revision, thus effectively ceding their hazard labeling regulations to the whims of the UN.
Some countries have gone beyond the Purple Book to add new hazards. For example, in the EU (and Australia), they have hazard classifications for “Explosive when dry” and “Toxic by eye contact” which are not in UN GHS. Likewise, in the US, they have added “Combustible Dusts”, “Asphyxiate Gases” and “Hazards Not Otherwise Classified”. Not to be outdone, Canada has added categories for “Biohazardous Infectious Materials” and “Water Activated Toxicity”. So, when doing an assessment for these countries, you may have additional hazards that you are required to report.
Finally, different countries may assign different GHS Hazard Statements to the same substance. For example, New Zealand and Taiwan assign hazard statement H319 “Causes serious eye irritation” to Formaldehyde whereas the EU and Korea do not. This is but another area where the GHS assessment can go awry.
So, in summary, “Is it Harmonized?”. The answer is a firm “maybe/sort of”. You can get different GHS assessments for the same product in different countries/jurisdictions. Certainly, GHS is a big step in the right direction, but it is clear that the complexities it creates requires a robust system to ensure that products are properly and accurately assessed.