It is not mandatory to use Supplier to Zero. However, most of the Signatory Brands require Supplier to Zero implementation of their suppliers.
It is highly recommended for suppliers to start with Supplier to Zero, as it supports them with the implementation of a sustainable chemical management system. Suppliers can start with Supplier to Zero Level 1 free of charge and without prerequisites.
Effective June 2023, some of the terminology is changed to align with the 2030 Impact Strategy. Certification levels within Supplier to Zero for non-signatory suppliers terminology has changed from Foundational, Progressive, and Aspirational Level to Supplier to Zero Levels 1, 2, and 3.
For more information regarding the updated terminology, please refer to the following Knowledge-Base article: New Terminology.