In today’s cyber security threat environment, we should consider adding cyber security considerations to our hazards analysis.
Process Hazards Analysis (PHA) or Hazard and Operability (HAZOP) studies of processes seek to identify malfunctions that might harm the people, process, or the environment. Quantitative and Qualitative Risk Analysis (QRA) is used to evaluate the actual risk to measurable criteria like financial exposure or the probability of failure.
Since many machines and processes are built with nothing more than a health and safety consideration, maybe we should start doing more analysis to determine if the machine or process can protect not only the people, but the machine itself, the process, and the environment. In fact, we should insure that the protections are valid even in the event of a hack, malware, or loss of network communications from a poorly performing industrial network.
By doing more analysis of the machine design, its implementation or the process, we might find that a simple protective device could prevent serious concern in the event of a malfunction or cyber security breach. For instance, by simply adding a mechanical over speed device to rotating machinery, the machine could be protected from over speed, even if a hacker managed to alter the speed of the machine undetected.
Realizing that building economical machines is important, but coming from a submarine nuclear power background, it strikes me that not considering these types of malfunctions, and protecting against them, has gotten us into the position we are today with cyber security threats.