2025 Spring Meeting and 21st Global Congress on Process Safety
(33n) Temporary By-Pass of Protection Layers: Risk Assessment and Management
Author
Perform process risk analysis studies allows the identification of existing protection layers for the risk scenarios raised. Regarding protection layers, CCPS (2012) highlights the relevance of some of them, such as: instrumented safety systems, relief or vacuum systems or devices, detection and alarm systems, etc.
Some situations, such as intervention/maintenance services, start-ups and shutdowns of operational units, may require the temporary deviation of protection layers, impacting the degree of risk of an existing scenario - affecting the relationship between frequency and consequence of a hazard becoming an accident.
Diverting a protection layer requires the adoption of a specific analysis, approval and communication protocol, which is capable of ensuring an adequate risk review, proposing the implementation of provisional measures for risk control whenever applicable.
In this case study, a management standard is proposed for temporary bypasses of protection layers according to the criticality of the scenarios to which these layers are associated - critical and non-critical, in an Oil Refinery, implemented through the use of a custom application created via Power Apps. It is worth noting that the bypass of a protection layer should always be considered as the last alternative, and when it is essential, it should remain installed for the shortest possible time.
Some situations, such as intervention/maintenance services, start-ups and shutdowns of operational units, may require the temporary deviation of protection layers, impacting the degree of risk of an existing scenario - affecting the relationship between frequency and consequence of a hazard becoming an accident.
Diverting a protection layer requires the adoption of a specific analysis, approval and communication protocol, which is capable of ensuring an adequate risk review, proposing the implementation of provisional measures for risk control whenever applicable.
In this case study, a management standard is proposed for temporary bypasses of protection layers according to the criticality of the scenarios to which these layers are associated - critical and non-critical, in an Oil Refinery, implemented through the use of a custom application created via Power Apps. It is worth noting that the bypass of a protection layer should always be considered as the last alternative, and when it is essential, it should remain installed for the shortest possible time.