Health and Safety Executive. Hazard assessment of well operations from vessels

Prepared by Team Energy Resources Limited. 2002y -30 pages. ISBN 0717625532 The use of dynamically positioned vessels rater than mobile drilling units is becoming more prevalent for intervention and maintenance of subsea wells. Recently the range of vessels being considered to perform this work has expanded to include diving vessels, ice breakers, ROV support vessels and other specialised vessels in order to minimise costs. The study identifies the risks associated with general well intervention and for various complexities of well intervention operations ranging from subsea xmas tree repairs to coiled tubing drilling and hydrocarbon storage. The main conclusions are: Operations from a dynamically positioned vessel should be safer than from a moored vessel Personnel competency in all aspects of the operations from technicians to management is critical Safety and management systems must be implemented and adhered to Proper planning, procedures and contingencies are essential for safe operations Isolations and barriers must be designed to cope with all contingencies Contents: Introduction Summary Objectives Methodology Conclusions Discussion Inventory of vessel requirements for Various operations Tabulated hazards.