The ZDHC MRSL V3.1 has been updated in response to queries from stakeholders and after discussion with the MRSL Council. The document has been updated to reflect changes in supplier guidance, formulation limits and in the note about the testing procedure for specific substances.

Also, a few frequently asked questions (FAQs) have been added to the ZDHC Knowledge Base to guide the stakeholders in the interpretation of test results and notes related to formulation limits helping them in certifying chemical formulation samples.

The different updates are as follows:

1. O-Phenylphenol (+salts) (CAS No. 90-43-7)

• The supplier guidance for the ‘Leather applicability’ of this substance in the category ‘1B. Anti-microbials and Biocides’ has been amended to:

"Use is permitted for chemical preservation for transportation and storage of raw hides as well as tanned semi-finished products (wet-white, wet-blue). Chemical preservation of coated or uncoated finished leather shall not be permitted."

• It is also permitted as an 'in-can preservative’ in leather chemical formulations under the BPR PT6 up to the formulation limit 5000 mg/kg.

2. Chlorophenols

To provide clarity to test laboratories and prevent misleading results, a ‘Note on testing’ is added in the introductory text of ‘1E. Chlorophenol’ category:

"If monochlorophenols or dichlorophenols are identified in a sample prepared for evaluation of Chlorophenols using KOH extraction, the results should be confirmed in accordance with Annex C of DIN-50009."

Please refer to this ZDHC Knowledge Base MRSL V3.1 and Conformance Guidance V2.0 - Frequently asked questions (Certifiers/Formulators) for more information.