DEXPI Standard
P&ID Exchange Format Explained

DEXPI (Data Exchange in the Process Industry) is the open standard for P&ID data exchange between process plant engineering software. Defined as an XML schema with explicit class hierarchy (ProcessBuilding → PipingNetworkSystem → ProcessInstrumentationFunction → Equipment + topological connections), DEXPI lets engineering tools export and ingest P&ID data without bespoke per-vendor format conversion. Maintained by the DEXPI working group, an independent industry initiative founded by AVEVA, BASF, Bayer, and other process industry stakeholders.

Not directly. DEXPI is an industry-managed open standard, maintained by the DEXPI working group rather than ISO. However, DEXPI aligns with and references ISO 15926 (the broader process plant lifecycle data semantic model maintained by ISO TC 184/SC 4 WG 3). DEXPI's RDL (Reference Data Library) sits on top of ISO 15926 reference classes. For P&ID exchange specifically, DEXPI is more practical than ISO 15926 because it has a defined XML schema; ISO 15926 is a semantic model that requires further specification for actual data exchange.

The DEXPI XML schema (XSD) defines the structure of a DEXPI document: which elements are valid, which attributes each element accepts, and which parent-child relationships are allowed. Current published version is DEXPI 1.4 with DEXPI 2.0 in working-group review (target finalisation 2026). The schema files are publicly available on the DEXPI working group repository. Key root element is ProcessBuilding; nested elements include PipingNetworkSystem (piping), ProcessInstrumentationFunction (instruments), Equipment (vessels / pumps / exchangers), and Connection (topology).

Different scopes. DEXPI is a P&ID exchange format: how P&ID data is encoded for exchange between engineering tools. CFIHOS 2.0 is an EPC-to-operations handover specification: which classes, attributes, and relationships an asset register must contain at handover. CFIHOS 2.0 sits on top of ISO 15926 (semantic model) and operates at a broader scope (full asset register, not just P&ID data). DEXPI handles the P&ID exchange layer specifically; CFIHOS handles the broader asset handover layer that includes equipment, instruments, lines, and operational metadata. Most asset owners use both: DEXPI for P&ID-tool-to-P&ID-tool exchange during engineering, CFIHOS for EPC-to-operations handover at the broader asset register level.

The DEXPI working group is an independent industry initiative founded by process plant operators (BASF, Bayer, Evonik, Covestro), engineering tool vendors (AVEVA, Hexagon, Siemens), and academic partners. It maintains the DEXPI specification, schema, and reference data library. Working group meets approximately quarterly; specification updates published openly. Pathnovo participates in DEXPI-aligned data exchange via output format support; broader working-group participation is on the Pathnovo standards-engagement roadmap.

Yes. AVEVA was a founding member of the DEXPI working group. AVEVA Diagrams (modern P&ID authoring module) and AVEVA Engineering / E3D suite support DEXPI export. DEXPI is one of the standard exchange formats AVEVA supports for interoperability with non-AVEVA engineering tools (Hexagon, Bentley OpenPlant, Siemens COMOS).

No. DEXPI is voluntary; adoption depends on owner-operator and EPC contractor specification. However, increasingly major owner-operators (BASF, Bayer, ADNOC, Aramco) specify DEXPI-compliant P&ID exchange as a project requirement. EPC contractors that cannot deliver DEXPI exchange increasingly lose competitive position on tier-1 owner-operator projects. For Pathnovo customers, DEXPI 2026 native output is included by default; no additional configuration required.

DEXPI XML output validates against the published DEXPI XSD schema using standard XML schema validation tools (xmllint on Linux / macOS, MSXML on Windows, equivalent libraries in any language). DEXPI working group also publishes example DEXPI files and validation tooling. Pathnovo's DEXPI output is validated automatically against the latest DEXPI schema version before delivery; validation report provided with every DEXPI deliverable.