Operators of offshore support vessels are now recognising DNV’s additional Class Notations Clean/Clean Design and Comfort, aimed at improving working conditions onboard.

Ships under construction with the Clean Notation now total close to 50. It focuses on operational issues to reduce risk of emissions to sea and air. DNVs Environmental Class consists of requirements focusing on cost-effective operational measures to minimise environmental impact.

The Comfort Class Notation COMF gives a standard for noise, vibration and indoor climate onboard ships, and aims at controlling the internal environment. It has proved useful for offshore support vessels operating for long periods at sea. The increase in number of incidents after long hours on watch, and several days in operation, indicates a need to control the crews work environment.

Analyses of several designs of offshore support vessels show noise levels higher than recommended by IMO and the new EC directive, unless several noise-reducing measures are taken. Using the COMF notation is an effective way to specify requirements and verify compliance through measurement of different environmental parameters. More than 15 offshore vessels will operate with the COMF Notation during 2002.