Chlorine Resistance Solutions for Swimwear: Sourcing Checklist for Buyers
Questions to put to any mill supplying swimwear with chlorine resistance specified.
Capability questions
Ask for the test equipment list and the standards used. The relevant method here is ISO 105-E03 chlorine water, and the mill should be able to show recent reports. Because the fabric stays wet, stretched and chemically exposed for hours, target checks are made on a worn sample rather than flat fabric alone.
Documentation
Request the technical data sheet, composition certificate and previous results for less than 15% modulus loss after 100 hours at 1 ppm chlorine. Consistent paperwork usually reflects consistent process control. Keep ISO 105-E03 chlorine water named in the tech pack so every lot is measured the same way.
Mill visit checks
Look at finishing conditions and testing frequency. Problems such as elastic loss and colour change after pool exposure often come from process drift rather than design. Where swimwear is worn for pool training and beach use, set tolerances around that range of movement.
Commercial terms
Confirm minimum quantity, lead time and the cost impact noted as premium elastane adds 8-12% to yarn cost before development work starts. Any change to nylon and polyester knits at 190-230 GSM with high elastane requires re-testing against less than 15% modulus loss after 100 hours at 1 ppm chlorine before bulk is released.
Warning signs
Be careful where samples perform differently from bulk, or where reports are only issued on request. Past reports from ISO 105-E03 chlorine water help the mill reproduce the same recipe on the next order.
