ISA-95 Architecture

ISA-95 levels

ISA-95 defines five levels: Level 0 (process), Level 1 (basic control), Level 2 (supervisory control: SCADA, HMI), Level 3 (manufacturing operations: MES), and Level 4 (business planning: ERP).

Functional hierarchy

The ISA-95 functional hierarchy defines the equipment, the process cell, the area, the site, and the enterprise.

Integration patterns

The integration patterns between the levels are defined per the data type, the frequency, the criticality, and the validation requirements.

Implementation roadmap

The ISA-95 implementation roadmap is a phased approach that builds the architecture layer by layer.

How to use this page

Use this ISA-95 Architecture page as a planning checkpoint before vendor selection, architecture review, validation scoping or implementation sequencing. The strongest next step is to compare the guidance with your current SOPs, system inventory, batch records, data flows and QA review routines so the discussion starts from evidence instead of assumptions.

Evidence to prepare

For ISA-95 Architecture, prepare the records, owners, risks and decision criteria linked to isa-95 levels, functional hierarchy, integration patterns, implementation roadmap. Useful evidence includes current process maps, interface lists, audit trail expectations, exception workflows, data retention rules and the business reason for changing the current operating model.

Frequently asked questions