Definition of ZDHC certification

The Zero Discharge of Hazardous Chemicals (ZDHC) Foundation is a non-governmental environmental organisation. As part of its efforts to raise environmental standards in the fashion, textiles, and leather industries, it runs a three-step certification scheme that certifies products contain no hazardous chemicals.

What is ZDHC certification?

ZDHC certification is a comprehensive method for assessing the amounts of hazardous chemicals that a company discharges in wastewater streams. There are three levels of compliance: 1,2 and 3. The higher the level, the greater the confidence that environmental standards have been met. 

The organisation advocates for three main principles: safer chemicals, smarter processes, and better outputs. Testing is conducted by third-party service providers, who work through the audit process alongside chemical manufacturers. For Level 3 testing, this means using MRSL testing and on-site chemical management audits to verify chemical and stewardship processes. 

As of 25 January 2024, Stahl has achieved ZDHC Level 3 certification for 2,151 products in our portfolio.

Why is ZDHC certification important?

In recent years, there has been growing concern about carbon centricity – the popular tendency to focus on carbon emissions at the expense of other issues. Emissions are certainly important, but they are just one of several factors affecting the health of our planet. In response to growing concerns about toxic water pollution, ZDHC was founded in 2011.

By achieving ZDHC certification, companies in the footwear, textile, and fashion industries can demonstrate their commitment to responsible chemistry management, progressing towards the goal of zero discharge of hazardous chemicals. As a leading partner of these industries, Stahl can make a significant impact through our specialty coatings and treatments.

What are the challenges associated with ZDHC certification?

Applying for ZDHC certification is voluntary, and many organisations are still reluctant to submit their products and facilities for testing – particularly if their environmental credentials are unverified. Organisations that do apply for ZDHC certification, therefore, face a significant challenge: how can they inspire their peers and others in their value chain to do the same? 

What is the future of ZDHC certification?


Two trends are likely to shape the future of ZDHC certification. First, we can expect to see growing customer concern over waste chemicals; in response to this, companies will take greater measures to guarantee their responsible practices, and ZDHC certification will become more commonplace. 

Second, the methodologies and technologies used in ZDHC certification will grow more advanced in the coming years. As the testing process becomes quicker, cheaper and easier, companies should be more motivated to get ZDHC-verified.

At Stahl, we are on a journey towards sustainable chemical management. As part of our ESG Roadmap to 2030, we have set a target for 100% of the Stahl portfolio in the footwear, garment and accessories segment to be ZDHC-certified by 2030.