It has been recognized for some time that quantitative risk analysis (
QRA) studies have historically shown a higher degree of variability in
result than is generally the case with other engineering analyses. Th
e European Benchmark Study on QRA technology highlighted several areas
of inconsistency. There has been a major increase in the emphasis on
quality, under the banner of either ISO 9000 or total quality manageme
nt. This paper discusses approaches which we have adopted to address b
oth the management of quality and the development of tools for offshor
e QRA which are compatible with the needs of formal quality assurance.
The management of quality is achieved partly by ISO 9000 business pro
cedures, but more importantly by a hierarchy of technical documents: a
consultancy policy, four guidelines and 17 technical notes, and a pro
cedure for deviations. These define the basic procedures, methods, dat
a and parameters that are the 'default set' for all QRA studies undert
aken by the company. While flexibility is retained to meet specific cl
ient needs, a greater degree of consistency and quality should result.
Unwanted variability should be eliminated and agreed deviations will
be properly documented. The use of formal standards such as these in r
isk studies will allow greater emphasis to be given to hazard identifi
cation and risk-reduction activities within a given budget. The tool e
nhancement relates to development of the Offshore Hazard and Risk Anal
ysis (OHRA) Toolkit, which is enabling the traditional spreadsheet app
roach for QRA, with its inherent quality assurance problems, to be pha
sed out. This paper summarizes specific features of the OHRA Toolkit w
hich assist in quality assurance.