Overview
ISO 6003:2017 specifies a laboratory measurement method for the mass and polar moment of inertia of alpine skis. The standard provides a repeatable test setup, conditioning and calibration procedures, and tolerance limits so that measurements published by manufacturers or testing bodies are comparable across laboratories.
Key practical points from the standard include controlled conditioning of the measurement device, a defined sampling strategy for representative ski lengths, and a verification/calibration step using a reference steel bar.
Key Topics
- Scope: Laboratory procedures for measuring mass and the polar moment of inertia of finished alpine skis (no accessories).
- Apparatus & conditioning:
- Accurate balance (±0.02 kg), knife to find the centre of gravity, accurate timing device (±0.1 s).
- Measurement device comprised of a suspension plate, two wires and a fixation element; wires should be low‑elasticity and high‑strength (diameter ≤ 1.0 mm).
- Devices and samples must be conditioned in an atmosphere of (20 ± 2) °C and (65 ± 1) % relative humidity for at least 24 hours prior to testing.
- Sampling: Recommended ski lengths for published results are 150 cm, 165 cm or 180 cm; choose the length most representative of the model tested.
- Calibration: Determine a correction factor c by comparing measured and theoretical polar inertia of a reference steel bar; c should lie between 0.9 and 1.1. If not, the measurement device must be adjusted.
- Measurement procedure:
- Measure mass, locate and mark the centre of gravity, mount the ski on the fixture centered at the CG.
- Rotate the ski to an angle of about 25° and release; record the time for five oscillation cycles.
- Compute the oscillation period and derive the polar moment of inertia using the period, ski mass and the suspension geometry (wire length and half‑spacing).
- Tolerances:
- Measurement repeatability: mass ±0.02 kg; polar moment of inertia ±0.02 kg·m².
- Published values relative tolerance: ±10 % for both mass and polar moment of inertia.
Applications
ISO 6003:2017 is used by ski manufacturers, test laboratories and certification bodies to:
- Produce comparable, calibrated mass and inertia data for product datasheets.
- Verify production consistency and report model‑level measurement values within defined tolerance bands.
- Support design validation, handling analysis and consumer information where mass and rotational inertia are relevant.
Related Standards
- ISO 6003:2017 should be cited in test reports and accompanied by required test details: reference to the standard, manufacturer name, model designation, nominal length and serial/production number, plus any deviations from the standard procedure.
Keywords: ISO 6003:2017, alpine skis, mass measurement, polar moment of inertia, laboratory method, calibration, tolerances, centre of gravity, test report.