GICSP vs. ISA/IEC 62443 Certification: Which OT Security Credential Should You Get in 2026?
GICSP is the better fit if you're coming from an IT/cybersecurity background and moving into hands-on OT defense work, especially in government- or defense-adjacent environments — it's a single proctored exam. ISA/IEC 62443 certificates are the better fit if you're a control-systems engineer, or you do design, governance, or compliance work — it's a four-tier certificate program with a mandatory prerequisite, not one exam. The two credentials test different things and target different job functions, so "which one" mostly comes down to what your job title already is, not which one is "harder" or "more respected." By The Whitepaper Skeptic — OT security architecture reviews and TCB/IR documentation prep Quick Facts Question Answer What is GICSP? A single proctored-exam credential from GIAC/SANS (82-115 questions, 3 hours, 71% pass bar), valid 4 years What is ISA/IEC 62443 certification? A four-tier certificate program (Fundamentals →...