Safe Diving on DP: Operational, Technical, and Regulatory Concerns and a Guidelines Standard
Authors: Beyerstein G.L. , Overland Terry 
Published: October 2008

This paper will introduce those concerned to the special Considerations that DP Diving Operations requires. It introduces regulatory, technical, operational and safety concerns and details a source of specific information for the safe and legal conduct of diving operations from a dynamically positioned diving platform.

INTRODUCTION

In North Sea waters it is routine to conduct diving operations from a dynamically positioned vessel. Domestically, the practice will become more prevalent, but experience is lacking. Safe diving operations from a DP vessel present a unique set of operation a land regulatory considerations, More than normal vessel, crew and adjacent structure safety considerations must be in effect. The diver?s life is directly in jeopardy from catastrophic events such as a power-off or rapid drift-off.

The Association of Diving Contractors has addressed these concerns and set out "Guidelines for the Specification and Operation of Dynamically Positioned Diving Support Vessels." These consensus standards draw heavily on the Guidelines issued in 1983 by the UK Department of Energy and the Norwegian Petroleum Directorate, but are tailored to domestic diving conditions. The DP vessel must be selected to match the work scope and to meet the requirements of the Guidelines. The capabilities of the vessel must be determined and operating limits established. Procedures must be developed covering normal operation, alerts, and emergency situations. Vessel and dive personnel capabilities also must be addressed. There must be sufficient crew having suitable training and experience to ensure safe operations. Lines of authority, responsibilities and communications must be Carefully detailed. The ADC Guidelines address these vital factors to foster the safe conduct of DP diving operations.

BASIC CONSIDERATIONS

Conducting diving operations from a dynamically positioned Support vessel involves four basic considerations:Regulatory ConstraintsVessel SpecificationOperating ProceduresPersonnel Capability

REGULATORY CONSTRAINTS

Commercial diving on the OCS falls under United States Cost Guard jurisdiction. The Federal Register Diving Regurecognizes four specific diving modes, SCUBA, surface-supplied air diving, surface-supplied mixed-gas diving, and Iive boating. The Coast Guard considering on DP as live boating. This mode prohibits diving operations from dusk to dawn or in restricted visibility, such as fog, making DP diving uneconomical. The regulations also have several other restrictions that combine to make DP diving impractical and illegal under the existing rules. The vessel?s propellers must be stopped before the diver enters or exits the water, and diving below 220 feet of sea water is prohibtied. Clearly. and diving from a DP platform is a special case outside existing regulations. Therefore, on DP, a variance, must be obtained.

The ADC Guidelines are the only standard recognized by the USCG. To date, it has been possible to obtain a variance from Coast Guard by agreement to accept and comply with the ADC Guidelines.