Overview
ISO 17491-3:2008 - “Protective clothing - Test methods for clothing providing protection against chemicals - Part 3: Determination of resistance to penetration by a jet of liquid (jet test)” specifies a repeatable, pass/fail test method for measuring inward liquid penetration of chemical protective clothing (Type 3, liquid-tight assemblies). The standard defines test liquids, apparatus, human test‑subject procedures, and reporting requirements for the jet test used to assess resistance to forceful liquid projection. It does not cover chemical permeation of materials.
Key topics and technical requirements
- Scope: Applies to clothing with liquid‑tight connections (seams, joins, interfaces with gloves/boots/hoods). Intended for clothing exposed to forceful liquid jets.
- Test principle: A water-based jet containing a fluorescent or visible dye is directed at selected test spots while a wearer dons an absorbent overall underneath to collect any inward leakage.
- Test liquid: Water (~20 ± 2 °C) with a water‑soluble dye (e.g., methyl blue), a surfactant and optional stabilizer. Surface tension must be (30 ± 5) × 10^-3 N/m and verified before and after each test.
- Jet nozzle and pressure:
- Nozzle opening dimensions: 4 ± 0.1 mm (length and diameter), inner tube ~12.5 ± 1 mm.
- Supply pressure at the nozzle: 150 ± 15 kPa (pump must supply ≥ 400 kPa capability).
- Nozzle distance to target: 1.0 ± 0.10 m, jet duration 5 ± 0.5 s per spot.
- Absorbent overall & calibration stain:
- One‑piece hooded absorbent overall collects penetrations; absorbency uniformity required.
- A calibration stain (25 ± 5 µL) producing a minimum area of 1 cm² is used as the reference for pass/fail evaluation.
- Test spots: Focus on critical areas - seams, seam crossings, zips/covered zips, overlaps and interfaces with other PPE. Each spot is marked and tested.
- Safety & test subjects: Tests use human subjects; the standard warns of hazards to eyes, face and body and requires subjects whose body dimensions fit the suit size.
- Reporting: Detailed test report required (test conditions, liquid composition, spot locations, number and area of penetration spots, pressure, temperature, preconditioning and photos).
Applications and users
- Useful for manufacturers and testers of chemical protective suits (Type 3) to verify liquid‑jet resistance of assemblies and connections.
- Employed by certification laboratories, quality assurance teams, PPE procurement specialists, and safety officers assessing PPE for industrial, emergency response, and hazardous‑materials operations.
- Supports compliance demonstrations for product standards and purchaser specifications.
Related standards
- EN 14605 - Performance requirements for Type 3/Type 4 protective clothing
- EN 340 - General requirements for protective clothing
- CEN/TR 15419 - Guidance on selection, use and maintenance of chemical protective clothing
Keywords: ISO 17491-3, jet test, protective clothing, chemical protective clothing, liquid penetration resistance, Type 3, absorbent overall, calibrated stain, nozzle pressure, test method.