ISO 10263-5:2009

Overview

ISO 10263-5:2009 defines a standardized test method for windscreen defrosting systems on earth‑moving machinery operator enclosures. The standard specifies how to prepare, execute and report laboratory or field tests that measure a defroster’s ability to remove ice/frost and maintain visibility on the windscreen under controlled cold‑weather conditions.

Key topics and technical requirements

• Scope: Tests apply to earth‑moving machines fitted with an operator enclosure and a windscreen defrosting device; tests may be performed in an environmental chamber or an appropriate outdoor environment.
• Test conditions: Maximum ambient temperature for heating tests is −15 °C with ambient wind speed up to 5 m/s. The machine is warmed per manufacturer procedure and run at rated speed under ≤20% rated net engine power.
• Heat transfer medium (HTM): HTM can be engine coolant, hydraulic oil or auxiliary heat source (air/liquid). HTM temperature is measured at the heater inlet.
• Ice application: Ice coating is created by spraying distilled water at 0.050 ± 0.005 ml/cm² using a nozzle ~1.7 mm diameter and ~345 kPa pressure, followed by a 30–40 min soak.
• Instrumentation & equipment: Environmental chamber (or outdoors), spray device, thermometer (±0.5 °C), anemometer (±0.5 m/s), rpm gauge (±2%), stopwatch, device to record defrosted area (tracing or digital camera).
• Procedure: After thermal soak and ice application, start the engine/heat source and run defroster at maximum blower speed. At 5‑minute intervals for 60 minutes, outline or photograph the defrosted areas.
• Performance criteria: Minimum percentage of defrosted area after 60 min is specified by windscreen type and area classification. Example minimums: one‑piece windscreens - Area A 99%, B 94%, C 80%; multiple‑piece - A 84%, B 70%, C 65%. Non‑defrosted portions must be confined to frame/moulding.
• Test report: Must include machine ID, ambient conditions, time to meet minimum area, defrosted‑area patterns (traced or photos), control settings and other test parameters.

Applications and who uses it

• Equipment OEMs validating cab HVAC and defroster designs
• Independent test laboratories performing cold‑weather certification
• Component suppliers (heater cores, blowers, auxiliary heaters)
• Fleet managers and safety regulators specifying minimum visibility performance
• R&D teams benchmarking heater/ducting effectiveness

Keywords: ISO 10263-5:2009, windscreen defrosting system test, earth‑moving machinery, operator enclosure, defrosting test method, HVAC, environmental chamber, HTM, defrosted area.

Related standards

• ISO 10263 series (Parts 1–6) - operator enclosure environment
• ISO 5353 - seat index point (SIP)
• ISO 9249 - engine net power test code
• ISO 5006, ISO 6165 - complementary ergonomic and machine classification standards