Establishing substance sameness
Companies manufacturing and importing the same substance have to register jointly. If the substances are not the same they should not register jointly. How can you decide when two substances are the same?
For a well-defined substance, apply the general principles from the guidance
Use the general principles described in section 5 of the Guidance for identification and naming of substances under REACH and CLP:
- Well-defined substances are considered the same if they consist of the same main constituents: their composition determines sameness.
- A mono-constituent substance is a substance where the main constituent is present at or above 80%.
- A multi-constituent substance is a substance where at least two constituents are present in amounts between 10% and 80%, and none of them above 80%.
- The degree of purity of a substance does not affect the sameness.
- Impurities resulting from the production process may differ for same substances.
- Technical grades, analytical grades or pure substances are the same as long as they consist of the same main constituent(s).
- Same substances may have a different purity/impurity profile depending on their grade.
When you are assessing whether you can register jointly with other companies, you may come to three different conclusions:
- You can definitely register jointly as your substances consist of the same main constituent(s);
- You definitely cannot register jointly as your substances do not consist of the same main constituent(s);
- A joint registration of the substances is possible, if justified. For example, where substances are on the border of being mono- and multi-constituent substances.
For a UVCB substance, look for examples and sector-specific guidance
If you have a substance of unknown or variable composition, complex reaction products or biological materials (UVCB), there is no common baseline which entitles the joint registration of substances.
Check the Guidance for identification and naming of substances under REACH and CLP for more detailed information on when two UVCB substances can and cannot be registered together. The composition, source and manufacturing process are critical factors for determining this.
You can also consult sector-specific support pages on ECHA's website. The sector-specific guidance, together with the official ECHA guidance, can help you to identify your substance correctly and achieve compliance with REACH in respect of substance identification. It will also help you make decisions on substance sameness.
See also under the Legislation section
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