PMEF — Plant Model Exchange Format

The open, cross-discipline 3D plant model exchange format

Specification · JSON Schemas · Examples · Adapters · Roadmap · Discord

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This project is under active development and not yet production-ready. All specifications, schemas, and catalogs are subject to change without notice. Use at your own risk. We are actively looking for supporters and contributors — whether you are an engineer, developer, standards expert, or domain specialist, your input is welcome. See CONTRIBUTING.md or join our Discord to get involved.

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What is PMEF?

PMEF is an open, semantically rich, cross-discipline 3D plant model exchange format for industrial facilities. It solves a problem that has cost the engineering industry billions in rework: every major plant design tool uses a completely isolated, proprietary data format.

Tool	Format	Open?	3D + Semantics?	Cross-discipline?
AVEVA E3D	RVM / Dabacon DB	Partial	✅	❌
Hexagon Smart 3D	VUE / SQL Server	❌	✅	❌
AutoCAD Plant 3D	PCF / DWG	Partial	Partial	❌
CADMATIC	3DDX / DGN	❌	✅	❌
Bentley OpenPlant	DGN / iModel	Partial	✅	Partial
PMEF	NDJSON + PMEFX	✅ 100%	✅	✅

PMEF provides:

• Canonical information model grounded in ISO 15926-14/IDO, DEXPI 2.0, CFIHOS V2.0
• Parametric geometry library (15 primitive types, RVM-inspired)
• Three geometry layers: parametric primitives · glTF 2.0 mesh · STEP AP242 B-Rep
• Git-friendly NDJSON serialisation with object-level versioning
• Bidirectional adapters for 14+ engineering tools across 8 disciplines
• Apache 2.0 Rust core library + thin adapter plugins

Disciplines covered

Piping · Equipment · Structural Steel · E&I · Pipe Stress · ERP/EAM · Simulation · Civil

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Quick Start

Validate an existing PMEF file

# Using the PMEF CLI (once published to crates.io)
cargo install pmef-cli
pmef validate my-plant.ndjson

# Or with Docker
docker run --rm -v $(pwd):/data ghcr.io/pmef/pmef-cli:latest validate /data/my-plant.ndjson

View the example

The examples/pump-skid-complete.ndjson contains a fully annotated pump skid (P-201A + V-201 + lines CW-201/202) with:

• pmef:Pump with API 610 spec, 3 nozzles, VFD drive
• pmef:Vessel with EN 13445 design, composite geometry
• Full piping run: Pipe → Elbow → Flange → Gasket → Valve
• Weld records, pipe support, fabrication spool

// Single object per line (NDJSON)
{"@type":"pmef:Pump","@id":"urn:pmef:obj:proj:P-201A","pmefVersion":"0.9.0",
 "equipmentBasic":{"tagNumber":"P-201A","equipmentClass":"CENTRIFUGAL_PUMP"},
 "pumpSpec":{"designFlow":450.0,"designHead":65.0,"motorPower":132.0,...},
 "nozzles":[{"nozzleId":"SUCTION","nominalDiameter":200,...}],
 "geometry":{"type":"parametric","ref":"urn:pmef:geom:proj:P-201A-prim"}}

Explore the schemas

All schemas live in schemas/. Open them in any JSON Schema-aware editor (VS Code, Insomnia, Stoplight Studio) for autocomplete.

schemas/
  pmef-base.schema.json            — shared primitives (IDs, coordinates, revisions)
  pmef-piping-component.schema.json— PipingNetworkSystem → PipingSegment → 12 component types
  pmef-equipment.schema.json       — 10 equipment types (Vessel, Pump, HX, Column, Reactor…)
  pmef-geometry.schema.json        — 15 parametric primitives
  pmef-property-sets.schema.json   — all property-set definitions (CFIHOS-aligned)

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Architecture

┌─────────────────────────────────────────────────────┐
│                  PMEF Package (.pmefx)               │
│                                                     │
│  model/           geometry/         catalogs/        │
│  ├─ piping.ndjson ├─ parametric.ndjson ├─ piping-spec│
│  ├─ equipment.ndjson├─ model.glb    └─ profiles      │
│  ├─ structural.ndjson├─ model.usdc                   │
│  └─ ei.ndjson     └─ model.stp      documents/       │
└─────────────────────────────────────────────────────┘
           ↑↓ bidirectional adapters
┌──────────┬──────────┬──────────┬──────────┬─────────┐
│AVEVA E3D │Smart 3D  │Plant 3D  │CADMATIC  │OpenPlant│
│Tekla     │Revit     │EPLAN P8  │COMOS     │INOSIM   │
│Creo      │CATIA     │TIA Portal│SAP EAM   │Emulate3D│
└──────────┴──────────┴──────────┴──────────┴─────────┘

Five-layer architecture

Layer	Content	Format
1 — Core Ontology	ISO 15926-14/IDO subset, DEXPI 2.0, IEC 81346, CFIHOS	OWL 2 (normative), JSON Schema
2 — Information Model	Entity types, relationships, property sets	JSON Schema Draft 2020-12 + UML
3 — Serialisation	NDJSON (primary), CAEX XML (secondary), AASX container	RFC 7464, IEC 62424
4 — Geometry	Parametric primitives, glTF 2.0 mesh, STEP AP242 B-Rep, OpenUSD	PMEF spec, Khronos, ISO 10303
5 — Adapters	Tool-specific import/export plugins	Rust crates (Apache 2.0)

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Repository Structure

pmef/specification
├── CHANGELOG.md               — version history
├── CONTRIBUTING.md            — how to contribute
├── ROADMAP.md                 — milestone plan
├── GOVERNANCE.md              — TSC and working group rules
├── CODE_OF_CONDUCT.md         — contributor covenant
│
├── spec/                      — normative specification (Markdown)
│   ├── 01-introduction.md
│   ├── 02-information-model.md
│   ├── 03-serialisation.md
│   ├── 04-geometry.md
│   ├── 05-adapters.md
│   └── 06-conformance.md
│
├── schemas/                   — JSON Schema (Draft 2020-12)
│   ├── pmef-base.schema.json
│   ├── pmef-piping-component.schema.json
│   ├── pmef-equipment.schema.json
│   ├── pmef-geometry.schema.json
│   └── pmef-property-sets.schema.json
│
├── diagrams/                  — Mermaid UML diagrams
│
├── examples/                  — annotated NDJSON reference instances
│   ├── pump-skid-complete.ndjson    (PMEF-DS-01)
│   ├── heat-exchanger-station.ndjson(PMEF-DS-02)
│   └── eaf-segment.ndjson           (PMEF-DS-05)
│
├── adapters/                  — adapter specifications (code in separate repos)
│   ├── plant3d/
│   ├── cadmatic/
│   ├── e3d/
│   └── openplant/
│
├── catalog/                   — open piping spec + profile catalogs
│   ├── profiles-en.json
│   ├── profiles-aisc.json
│   └── piping-class-a1a2.json
│
├── docs/                      — design docs and guides
│   ├── design-decisions.md
│   ├── iso15926-mapping.md
│   ├── dexpi-alignment.md
│   └── getting-started.md
│
└── .github/
    ├── workflows/             — CI/CD pipelines
    ├── ISSUE_TEMPLATE/        — bug, feature, RFC templates
    └── PULL_REQUEST_TEMPLATE/ — PR checklist

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Standards Alignment

PMEF is designed to complement, not replace, existing standards:

Standard	Relationship to PMEF
DEXPI 2.0	PMEF extends DEXPI — adds 3D geometry + cross-discipline; imports DEXPI P&ID entities
ISO 15926-14/IDO	PMEF's upper ontology; rdlType URIs resolve via PCA-RDL SPARQL endpoint
CFIHOS V2.0	PMEF property sets aligned to CFIHOS; PMEF exports CFIHOS-compatible handover packages
IFC 4.3	PMEF imports/exports IFC via IfcOpenShell; complements IFC for process plant specifics
AutomationML/CAEX	PMEF's XML serialisation is CAEX-compatible; AML AR APC for E&I/PLC data
IEC 81346	PMEF's iec81346 designation block uses IEC 81346 aspects (=, -, +)
ISO 19650	PMEF adopts ISO 19650 CDE workflow (WIP→SHARED→PUBLISHED→ARCHIVED)
AAS / IEC 63278	PMEF exports AAS submodels; PMEF-DEXPI submodel (IDTA 02016) aligned

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Contributing

We welcome contributions of all kinds — see CONTRIBUTING.md for details.

Quick links:

• 🐛 Report a bug
• 💡 Propose a feature
• 📝 Submit an RFC
• 💬 Join the Discord
• 📋 Good first issues

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Licence

Artefact	Licence
Specification (Markdown, schemas, diagrams)	CC BY 4.0
Reference implementation (Rust crates)	Apache 2.0
Examples and test data	CC0 1.0 — no rights reserved

© 2026 PMEF Contributors