TSA Insight Magazine Issue 6 - Magazine - Page 35
Figure 5: Human Reliability Rating
Making Improvements
Where the human error failure risk is high (poor reliability) then action must be taken to reduce the chance
of a critical error. This can be done by automating the task or where this is not practicable, by reducing the
PIF score or increasing the opportunity for recovery. This is shown in Figure 6.
Figure 6: Making improvements
A list of example improvement actions is available on request from the author.
Conclusions
The methodology outlined combines prioritisation of safety critical tasks to ensure that attention is focused
on the most critical safety related tasks and a two-stage reliability analysis looking at likelihood of error and
opportunity for recovery. This systematic approach has been shared with HSE and included attendance of
inspectors at a company workshop where the analysis was being applied to a large range of safety critical
tasks.
References
1.
COMAH Competent Authority Inspecting Human Factors at COMAH Establishments, (Operational Delivery Guide). https://www.
hse.gov.uk/comah/guidance/hf-delivery-guide.pdf
2.
Bow Ties in Risk Management – A concept book for process safety. Centre for Chemical Process Safety, CCPS, Energy Institute.
American Institute of Chemical Engineers and John Wiley & Sons, Inc. ISBN: 978-1-119-49039-5. https://publishing.energyinst.
org/__data/assets/file/0009/579888/Sample-pages-Bow-ties-in-risk-management-A-concept-book-for-process-safety.pdf
I s s u e
3
35