URN Identifier Patterns

ISO 80000 and IEC 80000 use separate URN namespaces. ISO parts follow RFC 5141 (URNs for ISO documents). IEC parts follow the IEC URN scheme.

ISO Parts

Parts published by ISO (2, 3, 4, 5, 7, 8, 9, 10, 11, 12) use the ISO standard URN namespace. The 2019 edition is edition 2.

Part-level URN

urn:iso:std:iso:80000:-{part}:ed-{edition}:{lang}

Example

urn:iso:std:iso:80000:-3:ed-2:en

ISO 80000-3 (Space and time), edition 2, English

Item-level URN

urn:iso:std:iso:80000:-{part}:ed-{edition}:{lang}:item:{num}

Example

urn:iso:std:iso:80000:-2:ed-2:en:item:2-8.19

ISO 80000-2 entry 2-8.19 (parentheses), edition 2

Bilingual (English + French)

urn:iso:std:iso:80000:-{part}:ed-{edition}:en,fr

urn:iso:std:iso:80000:-4:ed-2:en,fr:item:4-1

ISO 80000-4 entry 4-1 (length), bilingual

IEC Parts

Parts published by IEC (6, 13) use the IEC URN namespace with date-based editions.

IEC Part URN

urn:iec:std:iec:80000-6:2022-11:::

IEC 80000-6 (Electromagnetism), edition 2022-11

urn:iec:std:iec:80000-13:2025-02:::

IEC 80000-13 (Information science), edition 2025-02

URN Components

Component	Description	Example
urn:iso:std:iso:	ISO namespace per RFC 5141	urn:iso:std:iso
80000	Standard number	80000
-{part}	Part number (dash-prefixed)	-3, -2-8, -11-5
ed-{edition}	Edition number	ed-2 (2019 parts)
{lang}	Language code(s)	en, en,fr
item:{num}	Entry number within the part	item:4-1, item:2-8.19

ISQ Units & Dimensions

Units and dimensions from UnitsDB are identified using dual URNs — one in the ISO namespace, one in the IEC namespace — both incorporating the UnitsML identifier. This ensures every entity is addressable regardless of which publisher's URN scheme a consumer expects.

Unit URNs

ISO style

urn:iso:std:iso:80000:unit:{unitsml_id}

urn:iso:std:iso:80000:unit:u:meter

The metre

IEC style

urn:iec:std:iec:80000:unit:{unitsml_id}

urn:iec:std:iec:80000:unit:u:meter

The metre (IEC namespace)

Dimension URNs

ISO style

urn:iso:std:iso:80000:dim:{unitsml_id}

urn:iso:std:iso:80000:dim:d:length

The length dimension (L)

IEC style

urn:iec:std:iec:80000:dim:{unitsml_id}

urn:iec:std:iec:80000:dim:d:length

The length dimension (IEC namespace)

Dual URN for Entries

Every quantity and math entry in the ISQ carries two URNs — one in the ISO namespace and one in the IEC namespace — regardless of which organization published the specific part. This reflects the unified nature of the ISO 80000 & IEC 80000 series.

ISO style

urn:iso:std:iso:80000:-{part}:ed-{edition}:en:item:{num}

IEC style

urn:iec:std:iec:80000-{part}:{edDate}:::item:{num}

Example — length (t3-1.1)

urn:iso:std:iso:80000:-3:ed-2:en:item:3-1.1urn:iec:std:iec:80000-3:2019:::item:3-1.1

Edition Mapping

Publisher	Parts	Year	Edition
ISO	2, 3, 4, 5, 7, 9, 10, 11, 12	2019	2
ISO	8	2020	1
IEC	6	2022-11	2022-11
IEC	13	2025-02	2025-02

Note: The ISO 80000 series is not published as ISO/IEC 80000. It is a joint series where individual parts are published separately by ISO and IEC. Each part carries the publisher name of the organization that published it.