TECHOP Addressing C3EI2 to Eliminate Single Point Failures
Technical and Operational Guidance Notes
Evidence from DP incident data and learnings from incidents (LFIs) confirms that cross-connections, commonality, external interfaces, and external influences (in and on all parts of the DP system) continue to be significant causal and contributory factors in DP incidents. They are often the reason that failure effects exceed anticipated consequences and sometimes the worst-case failure design intent. This TECHOP contains examples from actual DP incidents associated with:
1. Cross-connections between redundant equipment groups.
2. Commonality shared between redundant groups.
3. External interfaces & influences (affecting DP system as a whole).