For these ships the class notation Offshore Service Vessel will be assigned, complemented by optional further notations, such as HNLS for ships carrying hazardous and noxious liquid substances, AH for anchor handling tug/supply ships, WSV for well stimulation vessels, and WTIS for wind turbine installation/construction support ships.
Design and operation of offshore vessels differ significantly from those of general cargo ships. Comprehensive international regulations are needed to specifically account for practical demands of OSVs. The new rules reflect today's offshore support vessels.
Compared to their predecessors, these ships are larger, more specialized, and technically more sophisticated to meet demands of complex deepwater field developments.
The latest review of the OSV rules are intended to support design and build safer and more robust offshore service vessels while minimizing operational risks.
Today, the term "supply" substitutes the broader term "support" or “service,” referring to an expanded definition of an OSV that includes not only traditional supply boats, but also anchor handling tug/supply ships, well stimulation ships, standby ships, and even ships built to carry hazardous and noxious substances, to fight fires, or to occasionally recover oil.