ISO 20283-3:2006

Overview

ISO 20283-3:2006 - Mechanical vibration - Measurement of vibration on ships - Part 3: Pre-installation vibration measurement of shipboard equipment provides guidance, requirements and procedures for measuring vibration produced by individual shipboard equipment during the factory acceptance test (FAT). The standard covers vibration measurements that represent structure‑borne sound sources to be transmitted into a ship’s structure and is applicable to passenger ships, merchant ships, yachts and high‑speed craft. It is a framework for producing representative, comparable test results but does not specify numerical acceptance limits.

Key topics and technical requirements

• Scope & purpose: Pre‑installation (FAT) measurement of translational vibration from machinery and equipment intended for shipboard installation; rotational vibration is not considered a primary contributor to structure‑borne sound in this part.
• Test frequency range: One‑third‑octave mid‑frequencies between 10 Hz and 10 kHz (modifiable by agreement).
• Measurement parameters: Vibration acceleration measurements (typically during steady‑state operating conditions); provisions for transient measurements if agreed.
• Measurement locations: On equipment feet or base (above mounts/isolators); for valves, on outlet flanges/nozzles and other structural connections (inlet excluded).
• Transducer mounting & orientation: Measurements in three orthogonal directions (one vertical); valves may be measured in two directions (parallel and perpendicular to flow). Accelerometer mounting follows ISO 5348 guidance.
• Mounting conditions: Defines practically free condition (soft/resilient mounts to approximate free suspension) and distinguishes rigid, compound and resilient mounts; discusses foundations, subbases and testbeds.
• Supporting requirements: Calibration, ambient vibration assessment, test system configuration, equipment operating conditions, data evaluation and test report content are all covered.
• Use of results: Measurements serve as inputs for shipbuilders to predict structure‑borne sound when combined with installation mount/foundation impedance.

Practical applications

• Select and compare low‑vibration machinery during procurement and FAT.
• Provide contractually agreed vibration data for shipbuilders and classification bodies.
• Supply representative source vibration data used to predict onboard structure‑borne sound and passenger/crew noise impact.
• Validate supplier test rigs, resilient mounting and alignment prior to delivery.

Who should use this standard

• Shipbuilders and naval architects
• Equipment suppliers and manufacturers (generators, HVAC, pumps, auxiliaries)
• Test laboratories and FAT engineers
• Vibration, acoustics and NVH specialists involved in shipboard installations
• Quality assurance and procurement teams specifying vibration acceptance criteria

Related standards

• ISO 31‑7, ISO 1683 (acoustic quantities/reference values)
• ISO 2041 (vibration vocabulary)
• ISO 5348 (accelerometer mounting)
• ISO/TR 13298 (ships & marine vocabulary)
• ISO 9611 (transducer locations - laboratory focus)
• Other parts of ISO 20283 (structural vibration, future parts on propulsion machinery)

Keywords: ISO 20283-3, ship vibration measurement, pre-installation vibration, factory acceptance test, structure-borne sound, shipboard equipment vibration, accelerometer mounting, vibration testing.