{
  "vercy": "1.0-draft",
  "publication": {
    "status": "research-draft",
    "adjudicationStatus": "unreviewed",
    "publishableCanonical": false,
    "generatedAt": "2026-09-11T04:35:51Z",
    "providers": [
      "Claude"
    ],
    "breadth": "written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify",
    "pass": 2,
    "wave": 1,
    "engine": "claude",
    "enrichment": {
      "pass": 3,
      "engine": "claude",
      "producedAt": "2026-10-05T15:00:00Z",
      "ingestedAt": "2026-10-05T13:11:18+00:00",
      "fields": [
        "agent_conduct",
        "ethics",
        "owners"
      ]
    },
    "gate": {
      "passed": true,
      "version": "1.0",
      "at": "2026-10-06T19:51:54+00:00",
      "evidence": [
        "completeness 1.00",
        "sense: Wikidata description",
        "2 live sources",
        "review by codex: pass"
      ]
    }
  },
  "metaModel": {
    "id": "THING-Q12511",
    "registryId": "vr.tr.stairs",
    "name": "stairs",
    "version": "0.2.0-wave.1",
    "entryKind": "thing",
    "family": "Thing Registry",
    "domain": [
      "PHY.BLT"
    ],
    "status": "research-draft"
  },
  "canonicalUrl": "https://ver.cy/models/thing/q12511/",
  "model": {
    "registry_id": "vr.tr.stairs",
    "name": "stairs",
    "purpose": "Let an agent treat stairs as a building element governed by geometry, safety and accessibility rules, and know when stairs are a barrier that needs an alternative.",
    "definition": "A construction of steps that lets people move on foot between levels, made of treads and risers arranged in one or more flights, with landings and usually handrails.",
    "what_it_is_for": "Moving people on foot between floors or levels, and providing escape routes in emergencies.",
    "affordances": [
      "climb and descend them, which some people cannot do",
      "design and build them, to building code geometry",
      "inspect them, for condition and compliance",
      "provide an alternative, such as a lift or ramp, where access requires one"
    ],
    "distinguishing_features": [
      "Consistent step geometry, which is what makes stairs safe",
      "A building element with code requirements, unlike informal steps",
      "A barrier to wheelchair users and some others, needing alternatives",
      "Escape stairs have extra requirements for fire protection and width"
    ],
    "appearance": "A series of horizontal treads rising in equal steps, with risers between them, landings at intervals, and handrails or balustrades along open sides.",
    "visual_identification": [
      "Regular treads and risers forming a flight",
      "Handrails and balustrades along the sides",
      "Stiles and ladders are related but steeper and treated differently by codes"
    ],
    "physical_properties": [
      {
        "quantity": "riser height",
        "typical_range": "150-190",
        "unit": "mm",
        "note": "codes set maximum riser heights"
      },
      {
        "quantity": "tread depth",
        "typical_range": "250-300",
        "unit": "mm",
        "note": ""
      },
      {
        "quantity": "pitch",
        "typical_range": "25-42",
        "unit": "degrees",
        "note": "steeper than about 42 degrees is usually a ladder or ship stair"
      },
      {
        "quantity": "handrail height",
        "typical_range": "850-1000",
        "unit": "mm",
        "note": ""
      }
    ],
    "families_and_kinds": [
      "by shape: straight, L-shaped, U-shaped, spiral, curved",
      "by use: main, service, escape, external, monumental",
      "by material: timber, concrete, steel, stone",
      "related forms: stiles, ladders, escalators"
    ],
    "related_models": [
      {
        "relation": "is part of",
        "target": "building",
        "why": "stairs are a building element"
      },
      {
        "relation": "is alternative to",
        "target": "lift and ramp",
        "why": "accessibility requires alternatives"
      },
      {
        "relation": "is regulated by",
        "target": "building code",
        "why": "geometry, guarding and fire rules"
      },
      {
        "relation": "is confused with",
        "target": "escalator",
        "why": "an escalator is a moving machine with its own standards"
      }
    ],
    "identifiers": [],
    "standards_and_regulation": [
      "National building codes on stair geometry and guarding",
      "Fire codes on escape stairs",
      "Accessibility standards such as ISO 21542"
    ],
    "failure_modes_and_hazards": [
      "Falls, among the most common causes of injury at home",
      "Irregular risers or worn treads that trip people",
      "Missing or low handrails and guarding",
      "Blocked escape stairs"
    ],
    "in_scope": [],
    "out_of_scope": [],
    "characteristics": [],
    "agent_conduct": {
      "may": [
        "Climb and descend stairs where it is designed and authorized to do so.",
        "Inspect stairs and report damage, loose treads or missing handrails.",
        "Guide people to an accessible alternative such as a lift or ramp."
      ],
      "must_not": [
        "Leave objects on stairs or block escape stairs.",
        "Push past or crowd people on stairs, especially those who are unsteady.",
        "Carry a person up or down stairs without their consent unless in an emergency."
      ],
      "requires_human": [
        "Moving a person who cannot use stairs during an evacuation."
      ]
    },
    "ethics": {
      "considerations": [
        "Stairs exclude people who cannot climb them; access requires alternatives.",
        "Falls on stairs seriously injure older people and children."
      ],
      "affected_parties": [
        "Older people",
        "Disabled people",
        "Young children"
      ]
    },
    "owners": {
      "steward": "The owner of the building; occupants and managers for upkeep.",
      "master_systems": []
    }
  },
  "sources": [
    {
      "id": "wikidata",
      "title": "Wikidata item Q12511: stairs",
      "url": "https://www.wikidata.org/wiki/Q12511",
      "url_status": "live",
      "what_it_supports": "identity and sense of the item",
      "checked_by": "wikidata-api"
    },
    {
      "id": "wikipedia-en",
      "title": "Wikipedia: Stairs",
      "url": "https://en.wikipedia.org/wiki/Stairs",
      "url_status": "live",
      "what_it_supports": "general description of the item",
      "checked_by": "wikidata-api sitelink"
    }
  ],
  "structure": {
    "bundles": [
      {
        "id": "geometry",
        "name": "Geometry",
        "description": "Rise, going and pitch.",
        "rationale": "Consistent geometry is what makes stairs safe to use.",
        "layers": [
          {
            "id": "steps",
            "name": "Steps",
            "description": "Riser and tread dimensions.",
            "findings": [
              {
                "id": "steps-finding",
                "name": "Step dimensions",
                "description": "The measured riser and tread sizes.",
                "questions": [
                  {
                    "text": "What are the riser height and tread depth, and are they consistent?",
                    "kind": "measurement"
                  },
                  {
                    "text": "Do they comply with the applicable code?",
                    "kind": "boundary"
                  }
                ]
              }
            ]
          },
          {
            "id": "layout",
            "name": "Layout",
            "description": "Flights, landings and width.",
            "findings": [
              {
                "id": "layout-finding",
                "name": "Stair layout",
                "description": "Flights, landings and clear width.",
                "questions": [
                  {
                    "text": "How many flights and landings are there, and how wide is the stair?",
                    "kind": "measurement"
                  },
                  {
                    "text": "Is headroom sufficient along the whole flight?",
                    "kind": "measurement"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "safety",
        "name": "Safety",
        "description": "Guarding and slip resistance.",
        "rationale": "Falls on stairs cause serious injuries, and most causes are designable out.",
        "layers": [
          {
            "id": "guarding",
            "name": "Handrails and guarding",
            "description": "Rails and balustrades.",
            "findings": [
              {
                "id": "guarding-finding",
                "name": "Guarding provision",
                "description": "Handrail and guard heights and continuity.",
                "questions": [
                  {
                    "text": "Are handrails and guards present, continuous and at the right height?",
                    "kind": "measurement"
                  },
                  {
                    "text": "Can a child climb or pass through the guarding?",
                    "kind": "boundary"
                  }
                ]
              }
            ]
          },
          {
            "id": "surface",
            "name": "Surface",
            "description": "Slip resistance and visibility.",
            "findings": [
              {
                "id": "surface-finding",
                "name": "Surface condition",
                "description": "Nosings, contrast and slip resistance.",
                "questions": [
                  {
                    "text": "Are the treads slip resistant, with visible nosings?",
                    "kind": "measurement"
                  },
                  {
                    "text": "Is lighting adequate?",
                    "kind": "measurement"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "access-and-escape",
        "name": "Access and escape",
        "description": "Who can use them and in emergencies.",
        "rationale": "Stairs exclude some people and are the escape route for others.",
        "layers": [
          {
            "id": "accessibility",
            "name": "Accessibility",
            "description": "Alternatives for those who cannot use stairs.",
            "findings": [
              {
                "id": "accessibility-finding",
                "name": "Alternatives provided",
                "description": "Lifts, ramps or evacuation aids.",
                "questions": [
                  {
                    "text": "What alternative exists for people who cannot use these stairs?",
                    "kind": "action"
                  },
                  {
                    "text": "How are they evacuated in an emergency?",
                    "kind": "action"
                  }
                ]
              }
            ]
          },
          {
            "id": "escape",
            "name": "Escape role",
            "description": "Fire protection and capacity.",
            "findings": [
              {
                "id": "escape-finding",
                "name": "Escape provision",
                "description": "Whether the stair is an escape route and its protection.",
                "questions": [
                  {
                    "text": "Is this an escape stair, and how is it protected from fire and smoke?",
                    "kind": "definition"
                  },
                  {
                    "text": "Is it kept clear?",
                    "kind": "measurement"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "construction-and-condition",
        "name": "Construction and condition",
        "description": "What it is made of and its state.",
        "rationale": "Material and condition decide maintenance and risk over time.",
        "layers": [
          {
            "id": "material",
            "name": "Material",
            "description": "Structure and finishes.",
            "findings": [
              {
                "id": "material-finding",
                "name": "Construction",
                "description": "The structure and finishes.",
                "questions": [
                  {
                    "text": "What is the stair made of, and how is it supported?",
                    "kind": "definition"
                  },
                  {
                    "text": "What load is it designed for?",
                    "kind": "measurement"
                  }
                ]
              }
            ]
          },
          {
            "id": "condition",
            "name": "Condition",
            "description": "Wear and damage.",
            "findings": [
              {
                "id": "condition-finding",
                "name": "Condition survey",
                "description": "Wear, damage and repairs needed.",
                "questions": [
                  {
                    "text": "What wear or damage is present?",
                    "kind": "measurement"
                  },
                  {
                    "text": "Who is responsible for repairs?",
                    "kind": "provenance"
                  }
                ]
              }
            ]
          }
        ]
      }
    ]
  },
  "openQuestions": [
    "Should escape stairs be a separate entry from stairs in general?",
    "How should accessibility alternatives be linked to stairs in a building model?",
    "Which geometry rules should the model carry across jurisdictions?"
  ],
  "statistics": {
    "bundles": 4,
    "layers": 8,
    "findings": 8,
    "questions": 16
  }
}
