ADR-0030: Identification has three peer routes, and The Plant can print QR labels

Status: Accepted — supersedes ADR-0004 Date: 2026-09-02

Decisions

D-62 QR, camera text recognition and manual search are three co-equal Identification routes

No route is the fallback of another. QR applies where The Plant has labelled a container; camera text applies where it has not; manual search always applies.

D-63 Curation can generate a printable QR label per Chemical Record

This is what makes the QR route real rather than theoretical. It is curation-side scope, not app scope.

D-64 Camera text recognition targets the CAS Number first, then the product name

ADR-0004's read order is preserved. The term is product name, not "chemical name" — a Formulated Product has none, and per D-18 those are the common case.

Context

ADR-0004 ranked QR secondary because "a plant with hundreds of drums will not pre-label them". Three things have changed:

• Web OCR is weak (D-41): camera text recognition is materially weaker than the native ML Kit assumption ADR-0019 was written under. It is the largest cost of the platform change and it lands on the source's most distinctive feature.
• The source treats them as peers (R-29): its caption reads วางฉลากหรือ QR Code ให้อยู่ในกรอบ — place the label or QR code in the frame. The source treats them as peers.
• The chosen stack already carries a QR decoding library. QR is free and reliable; only text recognition degrades.

The original reasoning also generalised from a hypothetical plant. This is a case study at one site (R-22). Labelling one production area is a realistic pilot activity and exactly the sort of thing a Safety Officer would do to make a tool work.

Rejected options

• Promote QR to primary — most reliable and cheapest on this platform, rejected because it would make the product useless until The Plant completes a labelling exercise, and the emergency case is the unfamiliar container nobody prepared.
• Keep QR secondary (ADR-0004 unchanged) — rejected: it leads with the capability the web does worst.
• Drop QR and align the glossary by deletion — rejected: it discards a free, reliable route and contradicts R-29.

This ruling may not be re-decided

If a change contradicts this ADR: stop and raise it. Do not implement over it. Do not demote manual search — ADR-0004's Consequences required it be first-class and D-41 made that load-bearing.

Coverage

Upstream	Landed in	Evidence	Note
R-29	D-62	the source caption treats label and QR as peers	supersedes ADR-0004's reading