textile manufacturing processes (MRSL, manufacturing restricted substance list) – specified in the STeP standard. A compilation of threshold concentration requirements for groups of chemicals and individual substances is included in the Eco Passport Standard. Analytical verification: Compliance with the restricted substance list's threshold concentration requirements is verified in a laboratory analysis of a product probe in an Oeko-Tex member institute. The Eco Passport by Oeko-Tex label can be issued to producers, traders and resellers of chemicals and is valid for one year. Certification process and control tests To have a textile or leather product certified by Oeko-Tex, manufacturers must supply samples of all components (including accessories like buttons, zips, studs, sewing threads, labels or prints) for analysis to a laboratory at one of the Oeko-Tex member institutes. The Oeko-Tex certificate is issued after successful testing of the materials for compliance with the Oeko-Tex standards and the signing of a declaration of conformity. Part of the certification process is also a company audit at the certified item's production facility, conducted shortly prior or after the issuing of the certificate. Later on, audits take place at least every three years. To verify continued compliance with the required limit values, the Oeko-Tex Association carries out annual checks for at least 25% of all issued Standard 100 and Leather Standard certificates. These checks involve unannounced company visits and laboratory tests of labelled product samples acquired from stores and production sites. Current information about withdrawn certificates is provided on the Oeko-Tex website. To ensure continued compliance with the requirements in the case of STeP certificates, Oeko-Tex carries out unannounced on-site visits at the production facilities. Other services by Oeko-Tex Detox to Zero by Oeko-Tex Detox to Zero is a service by Oeko-Tex that assesses the quality of a textile manufacturer's chemical management, chemicals used and waste water and sludge performance. The Detox to Zero status report is not a certificate, but a way for manufacturers to have their efforts towards reaching the goals of the Greenpeace Detox campaign verified, evaluated and documented by an independent institution. The Detox to Zero assessment evaluates the professional and transparent management of chemicals, the reduction respectively elimination of harmful substances from the production process and the quality of waste water and sludge. The status report can be issued for production facilities that use chemicals to manufacture, dye, print, coat or otherwise treat textile materials and textile products, and for