scope:

This Guide outlines the process and acceptance criteria to obtain the optional classification notation VIB-M based on vibration measurements. Compliance with the vibration acceptance criteria is to be verified to the satisfaction of the attending Surveyor through the measurement of the vibration of

i) Local structures

● Structures supporting the main propulsion system or other machinery and equipment, as well as nearby structures

● Structures in compartments of machinery and equipment that may be affected by the operation of the associated machinery and equipment

ii) Machinery and equipment specified in this Guide

Where major modifications to the vessel result in changes to the vibration characteristics of the vessel, new measurements are to be taken to maintain the notation. For sister vessels, measurements are to be carried out for each vessel.

The additional requirements provided in the Guide do not alter the mandatory class requirements of the ABS Rules for Building and Classing Marine Vessels (Marine Vessel Rules).

For aluminum structures as well as offshore units and installations, special consideration by ABS may be required to obtain this optional classification notation.