IEC 61511 is undergoing revision and one of the more welcome changes is inclusion of cyber security clauses. According to a presentation held by functional safety expert Dr. Angela Summers at the Mary Kay Instrument Symposium in January 2015, the following clauses are now included in the new draft – the standard is planned issued in 2016:
- Clause 8.2.4: Description of identified [security] threats for determination of requirements for additional risk reduction. There shall also be a description of measures taken to reduce or remove the hazards.
- Clause 11.2.12: The SIS design shall provide the necessary resilience against the identified security risks
What does this mean for asset owners? It obviously makes it a requirement to perform a cyber security risk assessment for the safety instrumented systems (SIS). Such information asset risk assessments should, of course, be performed in any case for automation and safety systems. This, however, makes it necessary to keep security under control to obtain compliance with IEC 61511 – something that is often overlooked today, as described in this previous post. Further, when performing a security study, it is important that also human factors and organizational factors are taken into account – a good technical perimeter defense does not help if the users are not up to the task and have sufficient awareness of the security problem.
In the respect of organizational context, the new Clause 11.2.12 is particularly interesting as it will require security awareness and organizational resilience planning to be integrated into the functional safety management planning. As noted by many others, we have seen a sharp rise in attacks on SCADA systems over the past few years – these security requirements will bring the reliability and security fields together and ensure better overall risk management for important industrial assets. These benefits, however, will only be achieved if practitioners take the full weight of the new requirements on board.