LR has released a new underwater noise notation and ShipRight procedure on underwater radiated noise with the intention of helping shipowners minimise underwater noise emissions when operating in sensitive environments.

Increased focus is being placed on underwater noise emissions from vessels and this is creating the need for a means of controlling underwater noise radiation. New international standards and regulations are anticipated, which will restrict access to environmentally sensitive areas and limit the types of vessels calling at ports to only those complying with stringent noise level standards.

Several countries and ports have already introduced speed restrictions in sensitive areas. Some ports even offer discounts in port fees if the ship has an underwater noise notation that certifies compliance with a set of underwater noise limits.

LR’s new underwater noise notation is based on the new ISO 17208 standards. LR actively participated in the development of these standards. The notation defines three criteria curves: Transit, Quiet and Research. The notation also includes a speed indication, e.g. ‘UWN-L(T20)’, which would mean that a vessel meets the underwater noise criteria in transit (T) at a speed of 20 knots.

In addition to testing and certifying vessels, LR will also work with shipowners during the design phase to predict and control the underwater noise emissions from vessels.

LR’s Per Trøjgård Andersen, Technical Lead – Engineering Dynamics, commented: “This new notation will not only help shipowners to reduce underwater noise radiation in sensitive environments. It will also demonstrate a commitment to environmentally friendly practices, and even has the added benefit of potential discounts in port fees.”

The ShipRight document can be downloaded here