(34)Specific concentration limits for substances should be assigned to a substance by a manufacturer, importer or downstream user in accordance with the criteria referred to in this Regulation, provided the manufacturer, importer or downstream user is able to justify the limits and informs the European Chemicals Agency (hereinafter referred to as ‘the Agency’) accordingly. However, specific concentration limits should not be set for harmonised hazard classes or differentiations for substances included in the harmonised classification and labelling tables annexed to this Regulation. Guidance should be provided by the Agency for the purpose of setting the specific concentration limits. In order to ensure uniformity, specific concentration limits should also be included, where appropriate, in cases of harmonised classifications. Specific concentration limits should take precedence over any other concentration limit for the purpose of classification.