Ontology Governance

How OpenConstruction Should Structure the Taxonomy

The ontology should be extensible, dataset-aware, and aligned with existing AEC standards. This page turns the governance Markdown into a proper site document and adds a clearer recommended structure.

Source Of Truth

`ontology/*.ttl` defines canonical concepts and hierarchy. Dataset labels map into it. Website taxonomies are derived views, not the authority.

Standards Strategy

Use Brick as the governance pattern, IFC and related buildingSMART concepts for AEC interoperability, and schema.org for web publication only.

Recommended Taxonomy Layers
  • Layer 1: Top concepts such as `Person`, `PPE`, `Construction Equipment`, `Vehicle`, `Structural Element`, `Architectural Element`, `Material`, `MEP Component`, `Defect`, and `Activity`.
  • Layer 2: Taxonomy classes such as `Crane`, `Wall`, `Rebar`, or `Hard Hat` families that organize semantically coherent branches.
  • Layer 3: Leaf concepts such as `Tower Crane`, `CMU Wall`, `Hard Hat (Blue)`, and `Asphalt` that can be mapped directly to dataset labels.
  • Layer 4: Mapping evidence where raw labels like `human`, `people-no-helmet`, or `vehicles > excavator` are recorded in dataset mapping files instead of being promoted to ontology canonicals.
Canonical Label Rules
  • Use singular, durable preferred labels: `Worker`, `Excavator`, `Hard Hat`.
  • Use `skos:altLabel` for true synonyms only.
  • Create narrower concepts when the semantics are more specific, not just because a dataset used a longer string.
  • Keep ambiguous labels such as `hat`, `pedestrian`, or generic `operator` separate until reviewed.
Decision Order For New Labels
  1. Check whether the raw label is an exact synonym of an existing concept.
  2. If not, decide whether it is a narrower concept that deserves its own class.
  3. If the dataset uses a bad parent bucket, preserve that in mapping metadata rather than changing ontology truth.
  4. If the meaning is ambiguous, leave it unmapped or reviewed instead of forcing a false equivalence.
AEC Standards Alignment
Brick-inspired governance IFC / buildingSMART alignment schema.org publication SKOS + OWL modeling
  • Brick is the pattern for stable URIs, preferred labels, synonyms, and a browsable concept graph.
  • IFC / buildingSMART should inform structural, architectural, and MEP concepts when semantics truly match.
  • schema.org is appropriate for website metadata and discoverability, not as the core construction ontology.
  • OpenConstruction mappings should remain the bridge between raw dataset labels and the canonical semantic layer.
Current High-Risk Terms
pedestrian hat hook vehicle operator person wall
Practical Rule For Contributors
  • Add ontology concepts in Turtle only when they represent stable domain meaning.
  • Add raw dataset labels to mapping files, not directly into the ontology as canonicals.
  • Keep the explorer and taxonomy views generated from or validated against the ontology.