{
  "vercy": "1.0-draft",
  "publication": {
    "status": "research-draft",
    "adjudicationStatus": "unreviewed",
    "publishableCanonical": false,
    "generatedAt": "2026-10-21T21:31:16Z",
    "providers": [
      "Claude"
    ],
    "breadth": "researched by Claude against the sources listed below",
    "pass": 2,
    "wave": 5,
    "engine": "claude",
    "gate": {
      "passed": true,
      "version": "1.0",
      "at": "2026-10-22T10:59:04+00:00",
      "evidence": [
        "completeness 1.00",
        "sense: Wikidata description",
        "6 live sources",
        "review by codex: pass"
      ]
    }
  },
  "metaModel": {
    "id": "THING-Q1550218",
    "registryId": "vr.tr.pit-prop",
    "name": "Pit prop",
    "version": "0.2.0-wave.5",
    "entryKind": "thing",
    "family": "Thing Registry",
    "domain": [
      "PHY.BLT"
    ],
    "status": "research-draft"
  },
  "canonicalUrl": "https://ver.cy/models/thing/q1550218/",
  "model": {
    "registry_id": "vr.tr.pit-prop",
    "name": "Pit prop",
    "purpose": "Let an agent describe pit props, their materials, use and history in mining, and point to mine safety rules.",
    "definition": "A timber post used to support the roof of underground workings, especially in coal mines, typically a length of round softwood such as pine; largely replaced by steel and hydraulic supports.",
    "what_it_is_for": "Supporting mine roofs to prevent falls of ground.",
    "affordances": [
      "describe materials and dimensions",
      "describe historical use and trade",
      "explain replacement by steel and hydraulic supports",
      "point to mine safety rules"
    ],
    "distinguishing_features": [
      "Some timber props creak or crack under load, historically valued as a warning, though warning is not guaranteed.",
      "Steel arches, roof bolts and powered supports displaced much timber propping; timber remains in some applications.",
      "Often pine or spruce; pit-prop timber was a major forestry trade, for example from Scandinavia to British coalfields."
    ],
    "appearance": "Round timber posts, often with a cap piece, set between floor and roof in mine workings.",
    "visual_identification": [
      "Vertical timber posts in old mine tunnels"
    ],
    "physical_properties": [
      {
        "quantity": "length",
        "typical_range": "about 0.6-2.7",
        "unit": "m",
        "note": "British peeled props, 1964 Forestry Commission guidance"
      },
      {
        "quantity": "diameter-to-length ratio",
        "typical_range": "about 1:12",
        "unit": "",
        "note": "historical rule of thumb"
      }
    ],
    "families_and_kinds": [
      "round timber props",
      "peeled and unpeeled props"
    ],
    "related_models": [
      {
        "relation": "is a kind of",
        "target": "mine support",
        "why": "mining"
      },
      {
        "relation": "is used in",
        "target": "coal mine",
        "why": "setting"
      },
      {
        "relation": "was displaced by",
        "target": "steel and hydraulic props and roof bolts",
        "why": "modern supports"
      },
      {
        "relation": "is made of",
        "target": "timber",
        "why": "material"
      }
    ],
    "identifiers": [],
    "standards_and_regulation": [
      "Mine safety regulations on ground support, by jurisdiction"
    ],
    "failure_modes_and_hazards": [
      "Roof falls when supports fail",
      "Decay of timber in old workings"
    ],
    "agent_conduct": {
      "may": [
        "describe props and history"
      ],
      "must_not": [
        "encourage entering old mine workings"
      ],
      "requires_human": [
        "ground support design by qualified mining engineers"
      ]
    },
    "ethics": {
      "considerations": [
        "miner safety"
      ],
      "affected_parties": [
        "miners"
      ]
    },
    "owners": {
      "steward": "the mine operator",
      "master_systems": []
    },
    "facets_not_applicable": {},
    "in_scope": [],
    "out_of_scope": [],
    "characteristics": []
  },
  "sources": [
    {
      "id": "SRC-001",
      "title": "Q1550218",
      "publisher": "Wikidata",
      "url": "https://www.wikidata.org/wiki/Q1550218",
      "what_it_supports": "identity of the registry item, labels and sitelinks",
      "url_status": "live"
    },
    {
      "id": "SRC-002",
      "title": "Pit prop",
      "publisher": "Wikipedia",
      "url": "https://en.wikipedia.org/wiki/Pit_prop",
      "what_it_supports": "general description of the subject",
      "url_status": "live"
    },
    {
      "id": "SRC-003",
      "title": "Forestry Practice, Bulletin 14, eighth edition",
      "publisher": "Forestry Commission",
      "url": "https://cdn.forestresearch.gov.uk/1964/03/fcbu014_8ed.pdf",
      "what_it_supports": "Round softwood mining timber, historical British dimensions, seasoning and variation in mine requirements.",
      "url_status": "live"
    },
    {
      "id": "SRC-004",
      "title": "Props",
      "publisher": "Store norske leksikon",
      "url": "https://snl.no/props",
      "what_it_supports": "Timber supports, spruce use and substantial Norwegian exports to English mines.",
      "url_status": "live"
    },
    {
      "id": "SRC-005",
      "title": "Forestry Commission Journal 32",
      "publisher": "Forestry Commission",
      "url": "https://cdn.forestresearch.gov.uk/1963/03/fcjo032.pdf",
      "what_it_supports": "Historical importance of pit-prop timber and its perceived warning function.",
      "url_status": "live"
    },
    {
      "id": "SRC-006",
      "title": "Fundamentals of Coal Mine Roof Support",
      "publisher": "CDC, National Institute for Occupational Safety and Health",
      "url": "https://stacks.cdc.gov/view/cdc/206364",
      "what_it_supports": "Timber and other standing supports, roof bolts, loading conditions and structural performance properties.",
      "url_status": "live"
    }
  ],
  "structure": {
    "bundles": [
      {
        "id": "prop",
        "name": "Prop",
        "description": "Which support.",
        "rationale": "Material and size.",
        "layers": [
          {
            "id": "material",
            "name": "Material",
            "description": "Timber or steel.",
            "findings": [
              {
                "id": "material",
                "name": "Material",
                "description": "Material and species.",
                "questions": [
                  {
                    "text": "What material is it?",
                    "kind": "provenance"
                  },
                  {
                    "text": "Which timber species?",
                    "kind": "provenance"
                  }
                ]
              }
            ]
          },
          {
            "id": "dimensions",
            "name": "Dimensions",
            "description": "Size.",
            "findings": [
              {
                "id": "dimensions",
                "name": "Dimensions",
                "description": "Length and diameter.",
                "questions": [
                  {
                    "text": "What are its length and diameter?",
                    "kind": "measurement"
                  },
                  {
                    "text": "For which seam height?",
                    "kind": "measurement"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "use",
        "name": "Use",
        "description": "In the mine.",
        "rationale": "Use follows design.",
        "layers": [
          {
            "id": "setting",
            "name": "Setting",
            "description": "Installation.",
            "findings": [
              {
                "id": "installation",
                "name": "Installation",
                "description": "Method.",
                "questions": [
                  {
                    "text": "How was it set?",
                    "kind": "provenance"
                  },
                  {
                    "text": "With cap pieces or wedges?",
                    "kind": "provenance"
                  }
                ]
              }
            ]
          },
          {
            "id": "support-plan",
            "name": "Support plan",
            "description": "Spacing.",
            "findings": [
              {
                "id": "support-plan",
                "name": "Support plan",
                "description": "Spacing and rule.",
                "questions": [
                  {
                    "text": "What spacing was required?",
                    "kind": "provenance"
                  },
                  {
                    "text": "By which rule?",
                    "kind": "provenance"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "history",
        "name": "History",
        "description": "Trade and replacement.",
        "rationale": "History explains decline.",
        "layers": [
          {
            "id": "trade",
            "name": "Trade",
            "description": "Timber supply.",
            "findings": [
              {
                "id": "trade",
                "name": "Trade",
                "description": "Source and period.",
                "questions": [
                  {
                    "text": "Where did props come from?",
                    "kind": "provenance"
                  },
                  {
                    "text": "When?",
                    "kind": "provenance"
                  }
                ]
              }
            ]
          },
          {
            "id": "replacement",
            "name": "Replacement",
            "description": "Steel and hydraulic.",
            "findings": [
              {
                "id": "replacement",
                "name": "Replacement",
                "description": "Technology and date.",
                "questions": [
                  {
                    "text": "When were timber props replaced?",
                    "kind": "provenance"
                  },
                  {
                    "text": "By what?",
                    "kind": "provenance"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "safety",
        "name": "Safety",
        "description": "Ground control.",
        "rationale": "Supports save lives.",
        "layers": [
          {
            "id": "failure",
            "name": "Failure",
            "description": "Roof falls.",
            "findings": [
              {
                "id": "failure",
                "name": "Failure",
                "description": "Event and cause.",
                "questions": [
                  {
                    "text": "Which failures occurred?",
                    "kind": "provenance"
                  },
                  {
                    "text": "Why?",
                    "kind": "provenance"
                  }
                ]
              }
            ]
          },
          {
            "id": "rules",
            "name": "Rules",
            "description": "Regulation.",
            "findings": [
              {
                "id": "rule",
                "name": "Rule",
                "description": "Law.",
                "questions": [
                  {
                    "text": "Which ground support rules applied?",
                    "kind": "provenance"
                  },
                  {
                    "text": "Who enforced them?",
                    "kind": "provenance"
                  }
                ]
              }
            ]
          }
        ]
      }
    ]
  },
  "openQuestions": [],
  "statistics": {
    "bundles": 4,
    "layers": 8,
    "findings": 8,
    "questions": 16
  }
}