Experiences of U.K. safety changes

David Knott
London

Legislation requires U.K. offshore operators to submit a safety manifesto for each of their installations to the Health & Safety Executive (HSE) by Nov. 30 (OGJ, Dec. 14, 1992, p. 25).

Safety cases for less than a quarter of the U.K.'s 200 plus fixed and mobile installations have so far been submitted. Hence the heightened interest of delegates in experiences of preparing safety cases during the Offshore Europe conference Sept. 7-10 in Aberdeen. John Kearns, Ian Sharp, and Donald Taylor of Hamilton Oil Co. Ltd., London, raised concerns that safety management system (SMS) concepts were borrowed from quality management practices without considering specific benefits.

Some work practices and initiatives are instigated because they are expected rather than because of need, they said in a conference paper.

Complacency warning

Formal procedures of all safety work made it easier to show that a system was safe, the Hamilton authors said. But too many procedures can lead to complacency.

Hamilton sought a balance by providing broad guidelines on individual safety responsibilities, backed up by rigorous staff selection and training.

"This approach provides a degree of confidence in an individual's ability to apply good judgement in his or her day to day work," the authors said. "This confidence allows a relaxation of the need for otherwise detailed procedural controls."

John Spittal of Amerada Hess Ltd. told delegates how the North Sea's Ivanhoe/Rob Roy field production unit underwent a trial safety case submission, which was reviewed by HSE and revamped before formal submission in June.

The Block 15/21a fields were developed via subsea manifolds tied back to AHOOI, a Sedco 700 series semisubmersible drilling rig converted to a floating production unit.

Floater's benefits

Spittal called AHOOI a good starting point in preparing a safety case. Wells are remote from production facilities, it is not high rise and therefore requires few lifting operations, and design changes were made after the 1988 Piper Alpha platform blast and before oil flow in July 1989.

Identification of major hazards on AHOOI was whittled down to fire or explosion, major structural damage, helicopter collision, failure of diving systems, and any event killing or injuring five or more crew members. These were further boiled down to two groups: loss of containment and dropped object hazards.

The main modifications arising from the safety case program were the fitting of two transverse pontoons and removal of all redundant deck equipment to provide space for process facilities.

"Identified hazards should be designed out, but where this is not practicable the hazards should be controlled by operational provisions," Spittat explained. "If neither design nor operational controls are effective, personal protective equipment should be provided."