The purpose of technical equivalence is to determine the similarity with regards to the chemical composition and hazard profile, of substances produced from a source different to the reference source or from the reference source but following a change to the manufacturing process and/or manufacturing location compared to the substance of the reference source in respect of which the initial risk assessment was carried out.

The technical equivalence of an active substance needs to be assessed in the context of biocidal product authorisation when there has been a change in regard to the source of the active substance. Relevant companies' obligations are described in Commission Delegated Regulation (EU) No 837/2013 amending Annex III to Regulation (EU) No 528/2012.

ECHA is responsible for assessing technical equivalence. The assessment is divided into two tiers and the applicant needs to indicate when submitting the application whether the application is for Tier I or for Tier II. In Tier I substance identity, chemical composition, analytical profile of five representative batches, description of the analytical method used for the determination of the substance and absorption spectra are assessed. If technical equivalence cannot be established based in Tier I, the applicant may ask ECHA to perform a Tier II assessment based on the hazard profile using toxicological and eco-toxicological data.

To assess the technical equivalence, companies need to submit an application through R4BP 3 to ECHA. Once ECHA has made the assessment, the applicant is given the opportunity to comments regarding the outcome of the assessment.  ECHA will take the final decision within 90 days from the date in which the application fee has been paid.