{
  "title": "Sampling populations and local hardness observations",
  "scope": "Specific eligible service/material cap-only production comparison-hardness method; no universal rule. Final-treated condition, WPS, line class, surface preparation and adopted hardness criterion remain required.",
  "selection": {
    "butt_min_percent": 10,
    "fillet_min_percent": 10,
    "basis": "Separately per WPS per line class",
    "locally_PWHT_welds_percent": 100
  },
  "local_observation": {
    "region": "Prepared weld cap only; not HAZ",
    "through_NPS6": {
      "positions": 2,
      "spacing_degrees_approximately": 180
    },
    "NPS8_and_above": {
      "positions": 4,
      "spacing_degrees_approximately": 90
    }
  },
  "hypothetical_example": {
    "butt_population": 100,
    "fillet_population": 20,
    "minimum_butt_selected": 10,
    "minimum_fillet_selected": 2,
    "NPS": 4,
    "cap_positions": 24,
    "counterexample": "12 butt/0 fillet is 10% combined but fails separate fillet minimum",
    "locally_PWHT_population": 0
  },
  "distinct_method": "Centre and adjacent HAZ readings with applicable material/process/welder/spool and furnace/local treatment population; not converted into cap-only coverage."
}