IEC 62443 Assessment and IACS Security

Service scope

• Definition of scope, roles, and applicable parts of the standard
• Risk assessment, zones-and-conduits design, and SL-T definition
• Assessment of system, process, and product-lifecycle requirements

Practical deliverables

• Clause-compliance and evidence matrix
• Gap and maturity report by accountable role
• IEC 62443 roadmap with priority, ownership, and acceptance criteria

What the IEC 62443 family addresses

IEC 62443 is not one document or a generic checklist; it is a family of standards for industrial automation and control system security. It addresses security programs, system risk assessment, technical requirements, secure product development, and service processes across distinct roles.

Asset owners, service providers or integrators, and product suppliers do not share identical responsibilities. The first step is to establish the role, IACS scope, system boundary, and applicable parts; otherwise an assessment becomes a collection of disconnected controls.

Risk, Zones and Conduits, and Security Levels

Assets with shared security needs are grouped into Zones, and communication between Zones crosses defined Conduits. The design must be grounded in assets, observed data flows, operational roles, threats, and consequences; a network diagram alone does not demonstrate effective segmentation.

A target Security Level, or SL-T, follows the risk analysis for each Zone. SL-C describes implemented capabilities and SL-A the assessed capabilities. These concepts should not be reduced to a marketing score or one uniform level for an entire site.

IACS security lifecycle and testable evidence

Security must continue from concept and design through procurement, integration, commissioning, operation, maintenance, and decommissioning. System security requirements, control ownership, acceptance criteria, change management, and evidence retention must remain explicit throughout the lifecycle.

ANP assessment outputs can include scope and roles, an evidence-based gap register, a Zone/Conduit model, SL-T review, a prioritized roadmap, and acceptance criteria. The service does not itself confer IEC 62443 certification or guarantee compliance.

Related guidance and services

IEC 62443 assessment for IACS security lifecycle, roles, risk analysis, Zones and Conduits, Security Levels, and an actionable roadmap—without certification claims.