{
  "schemaVersion": 1,
  "method": {
    "status": "Diagnostic comparison only. No accuracy acceptance threshold or certification.",
    "window_s": [
      60,
      599
    ],
    "windowBasis": "Project-selected diagnostic transient window, not the published FSRI steady-state evaluation window.",
    "alignment": "Source ignition Time; nearest integer solver second only within 0.001 s. No fitted time shift or response smoothing.",
    "geometry": {
      "width_m": 3.66,
      "depth_m": 3.66,
      "height_m": 2.44,
      "doorWidth_m": 0.9,
      "doorHeight_m": 2,
      "door": "open throughout"
    },
    "reduction": "Janssens/Tran-style temperature-profile reduction. Piecewise linear Kelvin profile; constant spatial extension from lowest sensor (0.34 m) to floor and highest sensor (2.415 m) to ceiling (2.44 m); bottom probe estimates lower temperature; reduce four quadrants separately, then unweighted mean only when all four are valid.",
    "sourceAdaptation": "FSRI report used CFAST 7.5.0, nominal 10-second HRR ramp and 15-second outputs; these runs use CFAST 7.7.7, measured HRR compressed from 601 to 200 knots and 1-second outputs. Source-informed adaptation, not reproduction or endorsement of the published evaluation.",
    "reference": "FSRI Assessment of Predictive Fire Algorithms and Models, printed pp. 13\u201314; independent source audit reproduced the formulas; this does not establish physical validity.",
    "formula": "I1=integral(T dz); I2=integral(1/T dz); z=Tl*(I1*I2-H^2)/(I1+Tl^2*I2-2*Tl*H); Tu=integral_z^H(T dz)/(H-z). T in kelvin.",
    "missing": "Nulls retained. No temporal interpolation of response measurements, imputation, or temporal response extrapolation. Spatial profile extensions are stated separately. Missing/nonphysical profiles excluded from derived-zone comparison. Independent valid local probes remain paired.",
    "oxygen": "FSRI sampled dry concentrations versus solver dry-equivalent percent = 100*wetO2Percent/(100-wetH2OPercent). Not raw wet oxygen.",
    "zoneAssignment": "Local probes above modeled interface use upper zone; at or below use lower. This is a modeling comparison, not probe equivalence to a zone mean.",
    "limits": [
      "Derived layer height is not a directly measured smoke interface.",
      "Thermocouples are local readings, not homogeneous zone averages.",
      "Time samples are correlated; pair count is not independent sample size.",
      "No confidence interval or uncertainty band is inferred from quadrant variation.",
      "Measured HRR is an input, not independent fire-growth prediction.",
      "This chamber comparison does not validate house geometry, tactics, tenability, furniture, spread or optical realism."
    ]
  },
  "cases": [
    {
      "id": "gas_back_replicate1_measured_600s",
      "file": "gas_back_replicate1_measured_600s.json",
      "sha256": "e289f36436a0a48f4e2de140a81c2e3b941f243e4cda857088f67f0d9fcb8891",
      "originalRole": "development",
      "evaluationStatus": "development"
    },
    {
      "id": "gas_back_replicate2_measured_600s",
      "file": "gas_back_replicate2_measured_600s.json",
      "sha256": "2507338af8a27e0a89ca1cffbb2a85ca896ac8f349235d19d95bf8a17bdb7ad2",
      "originalRole": "held-out-replicate",
      "evaluationStatus": "already-examined-after-original-input-freeze"
    },
    {
      "id": "gas_back_replicate3_measured_600s",
      "file": "gas_back_replicate3_measured_600s.json",
      "sha256": "7c9cdae1c243f304d2323ef75423777a378edcbe4588b25d4e102f5c030f4090",
      "originalRole": "held-out-replicate",
      "evaluationStatus": "already-examined-after-original-input-freeze"
    }
  ]
}