KPIs that are not part of ISO 22400 are fine to use, but they should be clearly distinguished from the ISO-defined indicators so people do not confuse local metrics with standardized ones.
Use a clear naming convention
In most plants, the simplest approach is to treat ISO 22400 KPIs as a “core” set and layer everything else on top:
- Label standard KPIs explicitly, for example: “OEE (ISO 22400-2)” or “Availability (ISO 22400-2)”.
- Label non-standard KPIs as custom or site-specific, for example: “Custom KPI – Setup Adherence” or “Site KPI – Rework Hours per Shipset”.
- Avoid implying ISO backing for anything not actually defined in ISO 22400. Do not call it “OEE” or reuse ISO KPI IDs unless the calculation matches the standard.
Differentiate by KPI family or domain
For clarity in dashboards and data models, group labels by type rather than trying to force everything into the ISO 22400 structure:
- ISO 22400 KPIs: Keep the names and calculation logic aligned with the standard wherever you claim ISO conformity.
- Operational extensions: Metrics that are plant-specific but still process/production focused (for example: “Fixture Changeovers per Day”, “NCR Cycle Time”). Label them as “Operational KPI – <name>”.
- Financial/COGS metrics: For example, COPQ, overtime cost, expedited freight cost. Label as “Financial KPI – <name>” and do not present them as ISO 22400 indicators.
- IT/availability metrics: For example, “MES Uptime”, “Interface Error Rate”. Label as “IT/Systems KPI – <name>”.
This makes it easier for quality, operations, and IT leadership to see what is standardized versus what is local or cross-functional.
Document definitions and data sources
In regulated and audit-prone environments, labeling alone is not enough. For any KPI outside ISO 22400:
- Maintain a KPI catalog with a unique ID, name, owner, calculation formula, data sources, and refresh frequency.
- Log differences from ISO 22400 where names overlap. For example, if you use a local definition of OEE, explicitly note that it is not the ISO 22400 calculation.
- Track system of record (MES, ERP, historian, QMS) so that disagreements about numbers can be traced back to a specific system and transformation logic.
This catalog should be under change control, especially if KPIs are used in management reviews, incentive schemes, or customer reporting.
Handle brownfield system coexistence
Because most plants already have KPIs baked into legacy MES/ERP/BI reports, you will often need to relabel existing metrics rather than redesign them:
- Map, do not overwrite: Keep legacy KPI names visible for a transition period, but add a label such as “Legacy KPI – <name> (not ISO 22400)” in your catalog and dashboards.
- Use calculated views in your BI layer to expose ISO 22400-aligned indicators alongside existing ones, each clearly labeled.
- Avoid disruptive renames in source systems (MES/ERP) that would require revalidation or extensive regression testing; adjust labeling and definitions in the reporting layer instead.
Full replacement of existing KPI logic in core systems is often high risk in regulated environments due to validation burden, traceability expectations, and the need to preserve long-term trending. It is usually safer to introduce ISO 22400 as an overlay and converge over time.
Practical labeling pattern
A pragmatic pattern that works across mixed-system environments is:
- Prefix or suffix all ISO KPIs with an “ISO 22400” tag in the name or description.
- Tag all others as custom/site-specific in both the data model and the dashboard (for example, description field: “Type: Custom KPI, not defined in ISO 22400”).
- Use KPI IDs (for example, “KPI-ISO-001”, “KPI-CUST-017”) so users can reference them consistently across MES, ERP, and BI tools.
This keeps the distinction auditable and reduces confusion when people compare metrics between plants, systems, or customer reports.
Governance and change control
Whatever label scheme you choose, treat it as part of your KPI governance model:
- Approve new custom KPIs through a cross-functional review (operations, quality, IT/data) before production use.
- Place KPI definition changes under formal change control if they affect regulatory submissions, customer SLAs, or management incentives.
- Version KPI definitions so you can explain historical shifts in trend lines when formulas or source data change.
This approach keeps flexibility for site-specific needs while maintaining clarity about which KPIs are ISO 22400-based and which are not.
