Concept

The concept is simple and certainly not a new one; in fact, considerable thought has been given over the years to having support vessels plying between platforms with personnel living onboard and transferring from the boat to the platform and vice versa. The concept, although eminently workable in many parts of the world where the waters are generally benign, has simply not been able to get off the ground in the North Sea purely because there was no truly safe means of transfer available to satisfy the Statutory Authorities. All of that has now changed with the introduction of the Offshore Access System, a system capable of providing safe "walk to work" access in varying sea state conditions of up to 2.5m significant wave height.

In 2003, the prototype of the OAS was successfully demonstrated in Amsterdam harbour but without a heave-compensation system being fitted. As a result of this, the unit was shipped to Qatar by an enthusiastic operating company, mounted on a vessel and operated successfully for a number of months.

It returned in 2004 to be fitted with a heave compensation system whereupon it was demonstrated offshore to potential clients, including a representative from ONEgas (Shell/NAM). ONEgas’ recognition of the potential productivity gains which could be achieved by this concept led to the development of the first operational Southern North Sea (SNS) OAS unit.

The OAS was designed and installed on the SMIT Kamara. After sea trials, performance reviews and acceptance testing, including competency assessment of the OAS operators, the unit was accepted into SNS operations in May 2006. The first operational unit has been working since then and has made over 1500 connections and disconnections without incident or accident.