Overview
ISO 16850:2007 specifies a standardized child head impact test method for evaluating pedestrian protection on the bonnet top of passenger cars and some light trucks (as defined in ISO 3833). The procedure simulates a frontal vehicle impact to a child pedestrian’s head using a free‑flight spherical head form impactor and computes the Head Injury Criterion (HIC) to assess head injury risk for impact velocities up to 11 m/s. The method focuses solely on head impact and does not address other body regions or full-body kinematics.
Key topics and technical requirements
- Purpose: Simulate lateral/frontal bonnet impacts to reduce child pedestrian head injury risk.
- Head form impactor:
- Spherical contact surface, 165 mm ±1 mm diameter (represents a 6‑year‑old head).
- Mass 3.5 ±0.07 kg; specified center of gravity and moment of inertia limits.
- Instrumentation: triaxial (or three uniaxial) accelerometers installed near geometric centre; CFC and calibration requirements per ISO 6487 and Annex B.
- Impactor temperature at impact: 20 ±2 °C.
- Impact geometry and conditions:
- Impact angle of the velocity vector: (53 ±2)° downward and rearward (see Annex C).
- Vehicle impact velocity simulated up to 11 m/s; launch to free flight with velocity measured per ISO 3784 (±0.1 m/s accuracy).
- Tests conducted on a flat, hard surface; vehicle in normal ride attitude.
- Impact area boundaries: bonnet top defined by wrap‑around distance (WAD) (1 000 mm front) and bonnet side reference lines; rear boundary by WAD 1 700 mm or bonnet rear reference line (BRRL).
- Data and metrics:
- Record acceleration time histories in line with ISO 6487.
- Compute HIC from resultant acceleration to quantify head injury risk.
- Report impact point, impact velocity, angle, atmospheric conditions and test instrumentation details.
Practical applications and who uses it
ISO 16850 is used by:
- Automotive OEMs and design engineers to evaluate and optimize bonnet geometry and front‑end compliance for child pedestrian safety.
- Independent crash test laboratories conducting repeatable child head impact testing.
- Regulatory bodies and certification programs assessing pedestrian protection performance.
- Research institutions studying vehicle–pedestrian interactions and head injury biomechanics.
Practical uses include bonnet design validation, comparative testing of vehicle models, and supporting safety improvements that may also benefit bicyclists in frontal impacts.
Related standards
- ISO 3784 - Measurement of impact velocity in collision tests
- ISO 3833 - Road vehicle types, terms and definitions
- ISO 6487 - Measurement techniques in impact tests (instrumentation)
Keywords: ISO 16850, pedestrian protection, child head impact test, HIC, head form impactor, bonnet top, wrap-around distance, bonnet side reference line, BRRL, vehicle impact velocity, test labs.