Overview
ISO 24231:2024 - Protective clothing - Protection against rain - Test method for ready-made garments against high‑energy droplets from above defines a laboratory method to evaluate the liquid tightness of rain protective garments. The method uses a static adult‑sized manikin exposed to a simulated heavy shower of high‑energy droplets (approximately 5 mm diameter) generated from a tower device. It applies to jackets, trousers, coats and one‑ or two‑piece suits and is intended to assess water ingress under intense vertical rainfall (not for snow, hail or strong wind resistance). Annex A gives background on the rain simulation and Annex B covers textile absorbency testing used for the manikin underwear.
Key topics and technical requirements
- Test principle: Dress a static manikin in absorbent underwear and the test garment, expose it to droplets from above, then inspect for wet areas and optionally record timing of ingress with humidity sensors.
- Tower device: Circular tub (≥1 000 mm diameter) mounted ≈5 000 mm above floor, with ≈682 nozzles (0.6 mm holes at 34 mm centres) delivering a droplet field ~932 mm diameter and a droplet density of ~2 000 droplets/m². Water depth in tub maintained at (45 ± 5) mm.
- Manikin and underwear: Manikin dimensions ~1 820 mm tall, chest girth ~1 000 mm. Underwear must be absorbent and show a mean wicking time ≤ 2 s when tested (Annex B).
- Test conditions: Water temperature within ±5 °C of room temperature; low‑calcium water to avoid nozzle blockage. Standard test duration is one hour, then a 2‑minute drain before inspection.
- Measurements and reporting: Record location and size of wet areas on the underwear, wicking lengths per relevant product standard, sensor timing (if used), test temperature, pre‑treatment, specimen count and any deviations. Minimum two specimens per garment type; if one fails, test a third.
Applications and who uses it
- Manufacturers: design validation, quality control and comparative performance claims for rainwear.
- Test laboratories / certification bodies: standardized method for product assessment and reporting.
- Procurement and specification teams: objective data for selecting protective clothing for outdoor work or emergency services.
- R&D and textile engineers: evaluate seam sealing, closures (zippers), hoods and fabric treatments (water repellency) under intense vertical rainfall.
- Useful for benchmarking against simulated cloudburst conditions and for identifying design weaknesses (zippers, hoods, hems, pockets).
Related standards
- ISO 11610 (vocabulary for protective clothing) - referenced for terms and definitions.
- Product‑specific standards may define pass/fail criteria (e.g., maximum wicking length) and additional pre‑treatments.
Keywords: ISO 24231:2024, protective clothing, rain protection, test method, manikin, liquid tightness, rain simulation, high‑energy droplets, tower device, waterproof testing.