Q: Which REACH Annex XVII entries affect zipper hardware?
Annex XVII restricts substances in articles rather than in the whole product. The entries most often relevant to a zipper are nickel release from parts in prolonged skin contact, azo colourants that can cleave to listed aromatic amines, polycyclic aromatic hydrocarbons in rubber or plastic parts, cadmium in plating and pigments, and lead in metallic components and coatings. Each entry has its own scope and its own limit.
For nickel, the limit is 0.5 micrograms per square centimetre per week, measured by the release method after wear simulation. For azo dyes the limit is commonly 30 mg/kg per listed amine on the dyed tape. PAH limits are set per substance and depend on whether the part is touched. Do not assume a limit applies to your part until you have read the entry's scope, and refer to the standard text for the test conditions.
The practical control is a material declaration per part plus spot testing on the finishes that carry risk: plated sliders, dyed tape, printed pulls and rubberised grips. Re-check when a coating or dye changes.