ADR-0009: Thai safety text is curated, never machine-translated at runtime

Status: Accepted Date: 2026-09-02

Decisions

D-11 Thai-published SDS are preferred; where only English exists, a human-reviewed translation is stored at curation time

The stored translation is a corpus artifact with its own provenance. The original-language span is always reachable from the translated view.

D-12 Safety text is never translated at runtime

Runtime machine translation of a safety span is the paraphrase D-02 forbids, in another language.

Context

R-18: the interface is Thai while chemical identity stays English. D-02 forbids paraphrase of safety content — and translation is paraphrase. A fluent translation can drop a negation: "use nitrile gloves; latex is not suitable" losing its second clause reads perfectly and is dangerous.

Thailand's Hazardous Substance Act requires SDS in Thai for hazardous substances sold domestically, so Thai-published SDS exist and remove the problem for part of the corpus. At 20-40 documents (D-04) reviewing the remainder is bounded work.

Rejected options

• Thai-published SDS only — rejected: zero translation risk, but it shrinks the corpus and may exclude chemicals the source names when no Thai SDS exists for them.
• English safety spans under Thai interface chrome — rejected: faithful to D-02 and free, but it fails the worker who cannot read technical English, which is much of the audience in R-03's settings.
• Runtime machine translation with a machine-translated warning — rejected: best coverage and least effort, and precisely the failure D-02 exists to prevent.

This ruling may not be re-decided

If a change contradicts this ADR: stop and raise it. Do not implement over it. Do not add runtime translation "just for chemicals we have not curated yet" — an uncurated chemical has no answer, and by D-03 the app says so.

Consequences

Curation cost per document rises and becomes the corpus bottleneck. That cost is itself a result for study objective R-04.2 and should be measured, not hidden.

Coverage

Upstream	Landed in	Evidence	Note
R-18	D-11	Thai-first interface with English chemical identity preserved