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Sector · AI · 05 Aug 2026

Citation ledger RL-4: the maintenance answer that quoted a retired SOP

Chunk IDs, doc versions, and refuse-to-answer rates decide whether plant RAG is knowledge or confident fiction—industrial AI citation ledger, not shadow-mode diaries alone, not label audits, not soft-sensor model cards.

Citation ledger RL-4: the maintenance answer that quoted a retired SOP

Ledger: RL-4 · On-prem maintenance RAG (read-only)
Sample: 40 technician questions, one week
Claim: “Answers are grounded — we show citations.”
Format: Citation failure ledger. Not a vector-DB vendor pitch.

Failure classes (counted)

| Class | Count | Example | | --- | --- | --- | | Correct cite + correct answer | 18 | — | | Correct cite + wrong synthesis | 7 | Right SOP, wrong torque | | Stale cite (retired rev) | 6 | SOP-441 Rev B cited; Rev D live | | Wrong chunk / wrong asset | 5 | Pump A procedure for Pump B | | Cite UI shown, chunk empty | 2 | Hallucinated footnote | | Should refuse, answered anyway | 2 | Safety interlock question |

Maintenance tablet showing AI answer with citation chips

A citation chip is not a verification. A revision match is.

Stale-cite autopsy (one row)

Question: “LOTO sequence for chiller-2 electrical.”
Cited: SOP-EL-19 Rev B.
Live: SOP-EL-19 Rev D (isolation point added).
Technician followed Rev B. Near-miss.
RAG “confidence” high. Ledger confidence: zero.

Ledger gates before wider rollout

  1. Every cite must resolve to doc ID + revision + chunk hash.
  2. If live rev ≠ indexed rev → hard refuse + reindex ticket.
  3. Safety / LOTO / SIS questions: refuse unless dual-source agree.
  4. Wrong-asset rate owned weekly by reliability + knowledge owner.
  5. Empty-chunk cites = sev-1 bug, not UI polish.

Document control shelf with revision-stamped SOP binders

If the index lags document control, the model is a rumor engine.

Adjacent fences

Shadow diaries own operator ignore rates. Label audits own vision truth. Soft-sensor cards own process proxies. Write-path red-teams own actuation risk. RL-4 owns whether citations are contracts. Do not scale a chatbot that quotes the dead revision politely.

Close

Grounding is not a footer. Grounding is a live revision. RL-4 counted the difference—and six technicians almost paid it.

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