Overview
ISO 9150:1988 specifies a standardized test method for evaluating the behaviour of materials used in protective clothing when struck by small splashes of molten metal. It forms part of a series of standards on clothing designed to protect against heat and fire. The procedure quantifies heat transfer through a test specimen by measuring the number of molten metal drops required to raise a sensor temperature behind the material by 40 K, enabling comparative assessment of pliable protective materials against small molten-metal splashes (commonly molten steel particles).
Key topics and technical requirements
- Scope and limitation: Applies to pliable materials or assemblies designed to protect workers from small splashes of molten metal; not intended to predict garment performance under all industrial conditions or behaviour with large molten-metal pools.
- Principle: Project molten-metal drops onto a vertically mounted specimen and record the number of drops required to produce a 40 K rise in an internal temperature sensor.
- Standard test specimen: Cut specimens 120 mm × 20 mm; prepare at least 10 specimens; condition per ISO 139 (standard atmospheres).
- Drop generation and control:
- Molten drops produced by fusion of steel rods in an oxy-acetylene torch.
- Target drop mass: m = 0.50 g ± 0.03 g.
- Drop frequency: f = 20 drops per 60 s ± 3 s.
- Steel rods: linear density ≈ 0.5 g/cm ± 0.2 g/cm.
- Sensor and support:
- Platinum-resistance sensor conforming to NFC 42-330 (100 Ω at 0 °C) embedded in a refractory insulating support block with specified thermal properties.
- Sensor discrimination capability: ±0.5 K.
- Apparatus details: Drop guide (PTFE funnel), adjustable specimen holder with counterweights, specified rod-to-sensor and rod-to-burner distances, and recommended gas flows to control drop size.
- Safety and environment: Tests must be in a draught-free room with adequate local exhaust; molten metal can pyrolyse organics - use protective gloves and eye/face protection when required.
- Reporting: Include sample description (surface density), reference to ISO 9150, individual and mean results for 10 specimens, noteworthy observations (smoke, flames), and any procedural deviations.
Applications and users
ISO 9150:1988 is valuable for:
- PPE manufacturers and textile developers comparing heat transfer resistance of fabrics against molten-metal splashes.
- Independent testing laboratories performing PPE testing and material qualification.
- Safety engineers and occupational health professionals specifying protective clothing for welding, foundry, and metalworking environments where molten steel particles may occur.
- Regulatory bodies and procurement teams requiring objective, repeatable test data for material selection.
Related standards
- ISO 139 - Standard atmospheres for conditioning and testing (referenced for specimen conditioning).
- NFC 42-330 - Platinum resistance temperature sensors (referenced for sensor specification).
- Prepared by ISO/TC 94 (Protective clothing and equipment).
Keywords: ISO 9150:1988, protective clothing, molten metal splashes, test method, PPE testing, molten steel particles, heat transfer resistance.
Open preview (PDF)Protective clothing — Determination of behaviour of materials on impact of small splashes of molten metal
