Skip to content

Class notations – Noise and Vibration

We offer three voluntary class notations: Comfort, vibration of machinery/equipment and underwater noise.

How can you show that you are truly committed to combatting noise and vibration?

Class notations are assigned to vessels in order to determine applicable rule requirements for assignment and retention of class. We offer three such notations on a voluntary basis.

Comfort Class

The Comfort Class is a systematic evaluation of the comfort on board different ship types. A rating from 1 to 3 reflects “high” to “acceptable” comfort standards. Ships are assigned a class notation COMF-V for noise and vibration and COMF-C for indoor climate.

Vibration Class

The Vibration Class includes procedures for where and how to measure vibration levels on different machinery, equipment and structures. It is based on values gained through numerous measurements. Ships meeting the requirements will be assigned class notation VIBR.

Silent Class

The Silent Class provides owners of acoustically sensitive vessels concise, realistic criteria regarding underwater noise emission. It also gives environmentally conscious owners an opportunity to demonstrate a low eco footprint. Compliant ships are given the SILENT notation.

DNV is your reliable partner:

  • Benefit from a trusted, recognised and independent partner on your side
  • Our class notations are recognised and accepted around the world
  • Boost your image as an environmentally friendly company
  • Increase your ship’s value on the market

Get more information on our class notations

  Comfort Class

Comfort Class

Download the flyer

  Vibration class

Vibration class

Download the flyer

  Silent class

Silent class

Download the flyer