ISA/IEC 62443 recognizes that some industries require sector-specific interpretations of cybersecurity controls. For the energy sector, ISO/IEC 27019 fills this role.

Step 1: Scope of ISO/IEC 27019

ISO/IEC 27019 provides information security controls specifically tailored for energy utility process control systems, including power generation, transmission, and distribution.

Step 2: Alignment with ISA/IEC 62443

ISO/IEC 27019 complements ISA/IEC 62443 by adapting ISMS-based controls to OT and ICS environments, addressing availability, safety, and real-time constraints.

Step 3: Why other options are less suitable

ISO/IEC 27001 is general-purpose and not ICS-specific. NIST SP 800-53 is broad and IT-centric. IEC PAS documents are not comprehensive sector standards.

Therefore, ISO/IEC 27019 is the most appropriate choice.