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properties /compliance

property free text free text

UN number

also called UN dangerous-goods number

The four-digit UN dangerous-goods number that identifies the substance for transport (UN1090 for acetone, UN3480 for lithium-ion batteries) — a flat compliance fact of the whole trade item, cardinality one, because a trade item has one transport classification independent of how many GHS hazard classes it carries. The literal value is the number as stated on the listing (one unbroken code, per the code-format law), so the language names the slot and the data layer fills the number — the live trade_identifier / regulatory_permit code precedent, a realised code the language names but never owns. Deliberately flat, not a qualifier of the card-many hazard-class host, since one class does not own it and repeating it per class would be redundant.

UN number is free text, written for one product alone and never shared as a category.

It belongs to compliance — where it is from and what it meets.

asked by the kinds that answer it

99 kinds answer it, each for a single value. The same question can be reused by unrelated kinds — one meaning, many homes.

answered with
free text — a literal — a free string that identifies one product, never a shared category.
value domain
code formats — the vocabulary its answers are drawn from.
concern
Compliance — the facet of a product it belongs to.

asked by kinds that answer it

The same question can be reused by unrelated kinds — one meaning, many homes.

kindhow many
Product one