Overview
ISO 22958:2021 - Textiles - Water resistance - Rain tests: exposure to a horizontal water spray - defines a standardized laboratory method to measure the water resistance of textile fabrics against impact (rain). The test predicts probable rain penetration by directing a controlled horizontal water spray at a fabric specimen and measuring the amount of water that penetrates onto a weighed blotting paper backing. It is especially suited to apparel fabrics and highly water‑resistant materials where small amounts of penetration are critical.
Key topics and technical requirements
- Test principle: A fabric specimen backed by a pre‑weighed blotter is exposed to a horizontal water spray for 5 minutes; the blotter is reweighed to determine water penetration.
- Specimen and blotter sizes: Typical specimen ≈ 200 × 200 mm; blotter ≈ 150 × 150 mm.
- Spray geometry: Specimen positioned centrally at 305 mm from the spray nozzle.
- Pressure head / spray intensity: Typical heads range from 610 mm to 1 830 mm. If unspecified, 600 mm can be used initially. Varying the head in 300 mm increments helps determine maximum no‑penetration head, penetration change with head, and the minimum head causing “breakdown” (> 5 g water).
- Test media and instrumentation: Use grade 3 water per ISO 3696 at specified temperatures (20 ±2 °C or 27 ±1 °C) and a laboratory balance accurate to 0.1 g.
- Conditioning and atmosphere: Follow ISO 139 for specimen and blotter conditioning (minimum 4 h).
- Evaluation and reporting: Report individual results and the mean for at least three specimens; include test parameters, water temperature, conditioning/ testing atmosphere, and any deviations.
Applications and users
ISO 22958:2021 is used to:
- Assess rain penetration performance of outdoor apparel, rainwear, lightweight coated fabrics, laminated composites, and certain textile combinations.
- Compare finishes (water‑resistant vs water‑repellent) or production lots during quality control.
- Support product specification, R&D, and claims about rain resistance for manufacturers, test labs, material scientists, and apparel designers.
Typical users: textile testing laboratories, outdoor and performance apparel manufacturers, quality assurance teams, technical designers, and standards compliance officers.
Related standards
- ISO 9865 - Bundesmann rain‑shower test (comparison/alternative method)
- ISO 139 - Conditioning and testing atmospheres for textiles
- ISO 3696 - Water for analytical laboratory use
- AATCC TM 35 - Rain resistance test method
Keywords: ISO 22958:2021, water resistance, rain tests, horizontal water spray, textile testing, apparel fabrics, pressure head, blotting paper, penetration resistance.