Overview
ISO 17608:2015 specifies a standardized laboratory method to determine the resistance of bare elastane yarns to chlorinated water (swimming‑pool water). The test evaluates how exposure to chlorinated aqueous environments affects yarn strength by measuring breaking force retention before and after treatment. This standard applies to bare elastane yarns only - results must not be used to predict fabric or finished garment performance.
Key topics and requirements
- Test principle: Measure breaking force retention (λ = F_after / F_before × 100%) of elastane yarns after exposure to chlorinated solutions.
- Exposure conditions: Three active‑chlorine concentrations are specified and two exposure durations are considered (24 h and 72 h). Temperature during exposure is controlled at 27 ± 2 °C.
- Apparatus: A water bath with a rotatable shaft and sealed stainless steel containers (rotated at 40 ± 2 r/min), a CRE (constant‑rate‑of‑extension) tensile machine, and a pre‑tension winding frame for yarn mounting.
- Reagents and solutions: Use deionized water (ISO 3696) and sodium hypochlorite stock solutions. Working solutions are prepared to contain 100 mg/L, 50 mg/L, or 20 mg/L active chlorine at pH 7.50 ± 0.05; all hypochlorite solutions should be prepared immediately prior to use.
- Specimen preparation & testing: From each package two samples are prepared - one for baseline (before exposure) and one for exposure. At least five specimens per sample are tested under prescribed gauge length, pre‑tension, and extension rate. Breaking force values are averaged and reported.
- Reporting: Test report must reference ISO 17608 and include sample identification, chlorine concentration, exposure time, pre‑tension, breaking forces before and after exposure, calculated retention (rounded to 0.1%), and any deviations or unusual observations.
Applications and users
ISO 17608:2015 is practical for:
- Yarn manufacturers assessing chlorine durability of elastane (spandex) yarn batches.
- Textile testing laboratories performing standardized comparative tests for supplier verification or quality control.
- R&D teams developing chlorine‑resistant elastane formulations or improvements.
- Procurement and specification writers who require objective test data when selecting elastane yarns for swimwear and aquatic textiles.
Note: Because yarn-level results do not predict fabric performance, fabric makers and garment manufacturers should complement yarn testing with appropriate fabric‑level tests.
Related standards
- ISO 105‑E03 - Colour fastness to chlorinated water (swimming‑pool water)
- ISO 5079 - Determination of breaking force and elongation of individual fibres
- ISO 139 - Standard atmospheres for conditioning and testing
- ISO 3696 - Water for analytical laboratory use
Keywords: ISO 17608:2015, bare elastane yarns, chlorinated water resistance, swimming‑pool water, breaking force retention, chlorine resistance testing, elastane testing, textiles standard.