Public evidence

engineering.uncertainty.tur

Machine-checked verification for calculation version 1.0.0 · tier engine_tested

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Verification

11/11 calculation tests · Production surface contract 4/4

Golden tests 0 / 0
Boundary tests 7 / 7
Property tests 4 / 4
Production surface contract 4 / 4
Engine tested Yes
Source checked Yes
Artifact integrity PASS
Production attestation Embedded snapshot: STALE · Last attested schema matched 1.0.0 snapshot / local build · Semantic contract ✓ · Last attestation PASS · current evidence changed · re-attestation required · Public/cache ✓ · Origin ✓ · Live production status PASS (0 stale; 164 CURRENT) @ 2026-09-16T06:44:24.909Z
Semantic contract PASS
Evidence attested at 2026-09-16T06:44:24.203Z
Last production check 2026-09-16T06:44:24.203Z
Public / cache PASS
Origin PASS
Supplemental domain review Not performed
Named expert review Not performed

release artifacts aligned PASS
schema valid input executes PASS
engine success output validates schema PASS
schema rejects incomplete input PASS

Fingerprint sha256:6670bb6fd6b5ff58d7e5723e9cd8311d2a35867456513cabc96b2bc485a5a630

Input schema sha256:5e0960bf982d1ca2ce4ea81ca745780566f63eb54e3fd1e3ea4cad5d064f612b · Output schema sha256:027acffc35b147221bccb965c946bcbefecd6d6a0d9481b122a028458a13a3a0 · Build-time SHA-256 digests prove published artifacts agree with each other (release_integrity.scope=workspace). Production attestation GETs canonical URLs twice (public/cached view and origin), including Capability HTML, via npm run attest:production --write (published at /.well-known/calculatorx-production-attestation.json) and fails if the public Capability page advertises a different calculation_version. This is artifact consistency, not an independent immutable release log.

Build & scope

Engine identity and declared limitations.

Tool: tur
Engine: tur
Engine build: 2026-09-16
Evidence core: 2026-09-16T21:07:40.795Z
Rendered: 2026-09-16T22:38:08.852Z
Last reviewed: —

Assumptions

ANSI/NCSL Z540.3 two-sided TUR = (USL−LSL)/(2U)
U is already expanded; this page does not compute U = k·u_c
tol is a half-width (span = 2·tol)
Not a pass/fail, not a guard band, and not combined RSS

Limitations

U is already expanded — this page does not compute U = k·u_c
Does not combine a measurement model or RSS of u_i
Does not issue a TUR≥4 pass/fail or an ILAC G8 decision
Not a guard band and not Cp/Cpk

Sources

Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.

ANSI/NCSL Z540.3 — Requirements for the Calibration of Measuring and Test Equipment — Test uncertainty ratio (two-sided TUR = specification span / 2U)
Supports: TUR = (USL−LSL)/(2U) for a two-sided specification and an already-expanded U
ILAC G8:09/2019 — Guidelines on Decision Rules and Statements of Conformity — Decision rules are a different contract from TUR
Supports: This page does not implement ILAC G8 guarded acceptance or a pass/fail

Published checks

Golden, boundary, and property cases included in this evidence build.

ID	Kind	Status	Detail
`boundary-tur`	boundary	pass	Expected TUR=4 · T=4 · U=0.5 · Actual TUR=4 · T=4 · U=0.5 · lsl=0 · usl=4
`boundary-tur-T`	boundary	pass	Expected TUR=4 · T=4 · Actual TUR=4 · T=4 · U=0.5
`boundary-tur-tol`	boundary	pass	Expected TUR=4 · T=4 · Actual TUR=4 · T=4 · U=0.5 · tol=2
`boundary-tur-missing-U`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`boundary-tur-missing-spec`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`boundary-tur-U`	boundary	pass	Expected VALUE_MUST_BE_POSITIVE · Actual VALUE_MUST_BE_POSITIVE
`boundary-tur-both`	boundary	pass	Expected INVALID_INPUT · Actual INVALID_INPUT
`property-tur`	property	pass	4
`property-tur-T`	property	pass	4
`property-tur-span`	property	pass	4
`property-tur-tol`	property	pass	4