Using Process Safety Management techniques, we design and implement multiple layers of protection for our hazardous plants. For these barriers to remain effective over the life of the asset is a challenge, particularly with aging assets. We know barriers deteriorate over time without proper, preventative maintenance and inspection. Often a lack of focus on critical barriers can result in activities being deferred or cancelled without recognizing the potential consequence.
There is generally a lack of understanding in our organizations of process safety techniques and approaches. While the criticality of these barriers maybe well-understood in the Process Safety department, this is unlikely true through other organizations, including Operations and Maintenance.
With so much equipment being tagged “safety critical” on our facilities, it is often difficult to ensure safety barriers receive the focus they need to ensure their effectiveness at protecting against high consequences events when needed. Operators need to manage the health of their barriers in near real-time and mitigate the impact arising from any impairments.
By understanding dynamic aspects of cumulative risk, all members of an organization can easily identify barrier impairments. This level of visibility helps make better operational activity management decisions on account of operational activities’ potential impact on Major Accident Hazard barriers.
This paper will examine the traditional approach to barrier design and assumptions on reliability, the approach to maintenance, and the reality of operational dynamics. It will introduce the concept of cumulative risk impacts on safety barriers and examine operational dynamics which impact barrier performance.