# Steel door dataset: field definitions

Version 1.2.0. Verified September 16, 2026.

**`weight_basis_oz_per_sqft`** — Published ounces-per-square-foot column of 15 U.S.C. §206 for gauges 3–30, not its distinct thickness column.

**`weight_basis_computed_in`** — weight_basis_oz_per_sqft / 669.12; a declared reconstruction using Clopay’s reference constant. Rounded to four decimals, not a published requirement, excluded from spread.

**`gsg_galvanized_nominal_in`** — Steel Source Galvanized table nominal, not a declared coating class or measured sheet.

**`msg_nominal_published_in`** — Steel Source Hot Rolled/P&O/Cold Rolled nominal as printed.

**`supplier_lower_ordering_limit_in`** — Steel Source Hot Rolled/P&O/Cold Rolled lower ordering limit, not a universal mill contract.

**`dasma_tds154_min_in`** — DASMA TDS154 bare-steel minimum as printed.

**`dasma_g60_in`** — DASMA TDS154 G-60 figure, including coating.

**`dasma_g90_in`** — DASMA TDS154 G-90 figure, including coating.

**`sdi_117_26_min_in`** — SDI117-26 §4.1 minimum reference, seven gauges only.

**`sdi_a250_8_table2_pub_mm`** — Metric value printed in A250.8-2023 Table 2, Models 1 and 2, only gauges20,18,16,14.

**`hmma_803_min_in`** — Minimum uncoated steel in HMMA803-08, 15 gauges.

**`hmma_803_pub_mm`** — HMMA803-08 printed reference millimeters, preserved without mathematical correction.

**`calculated_mm_of_hollow_metal_min`** — Cited inch minimum × exactly25.4; four-decimal display; not a replacement for the source’s printed metric.

**`lowest_published_in`** — Minimum across published galvanized nominal, uncoated nominal, supplier lower limit, DASMA bare minimum and available SDI/HMMA minimum. Computed weight column excluded.

**`highest_published_in`** — Maximum across the same five displayed published-value columns. Computed weight column excluded.

**`spread_pct`** — 100 × (highest_published_in / lowest_published_in −1), rounded once to one decimal; unlike-basis comparison, not tolerance or product variability.

**`distinct_published_values`** — Count of distinct decimal values in the five published-value columns used for spread; repeated source values counted once.

**`calculated_uninterrupted_days_at_15_cycles_per_min`** — cycles_required/(15×60×24), rounded one decimal; arithmetic illustration excluding inspections and stops, not observed runtime or service life.

**`qualification`** — Mandatory context/alternatives for component thickness; read together with min_thickness_in.

**`verification`** — star indicates primary-source inputs directly checked; calculated outputs separately reproduced; no pending tier in public numeric records.

**`date_checked`** — Date of this verification pass, not publication date of the underlying source.

**`blank_and_null`** — Blank CSV cells and JSON null mean absent/not applicable to that source field; never zero.


## Reproducing the calculations

Keep `reproduce-steel-door-data.py`, `source-inputs.json`, the four main CSV files, the source-register CSV and the combined JSON in the same directory. Run:

```bash
python reproduce-steel-door-data.py
```

The script checks the saved published inputs, recomputes spreads, weight-based references, conversions, coating comparisons and endurance durations, and checks the CSV/JSON agreement. It reports mismatches and exits unsuccessfully if a check fails. It does not fetch websites, perform physical measurements, revise source editions, or advance verification dates. Run `python reproduce-steel-door-data.py --help` for optional report and recomputed-data output paths.