ABSTRACT
A method has been developed for performing Hazard and Operability studies of drilling systems and procedures. The need for such a technique is explained and its development and application are described. Although the Drillers' HAZOP uses the same basic method as the traditional "process" HAZOP, novel features have been introduced for the analysis of those drilling operations which are essentially sequences of mechanical and manual handling operations by teams of people. For these cases, a new type of master document, the Multiple Activity Chart, has been developed and refined to be the basis for critical study by deviation analysis. It has been found that the set of guide word-variable combinations used in the classical HAZOP study is not suitable for analysis of Multiple Activity Charts; an alternative set has been developed and is described. The experience gained in development of the new method through a programme of case studies, and by virtue of its first practical application, is reviewed. This experience has demonstrated that use of the method can result in improved safety and efficiency in drilling operations. Finally, the authors discuss their plans for the future use and development of the technique.
