ISO 8601-2:2019

Date and time — Representations for information interchange — Part 2: Extensions

This document specifies additional representations of dates of the Gregorian calendar and times based on the 24-hour clock that extend the basic rules and composite elements of those defined in ISO 8601-1. These representations are specified as character strings for use in information interchange. It is also applicable for representing times and time shifts based on Coordinated Universal Time (UTC). These extensions include: — uncertain or approximate dates, or dates with portions unspecified; — extended time intervals; — divisions of a year; — sets and choices of calendar dates; — grouped time scale units; — repeat rules for recurring time intervals; and — date and time arithmetic. This document excludes the representation of date elements from non-Gregorian calendars, or times not from the 24-hour clock. This document does not address character encoding of representations specified in this document.

Date et heure — Représentations pour l'échange d'information — Partie 2: Extensions

General Information

• Status: Published
• Publication Date: 24-Feb-2019
• ICS: 01.140.30 - Documents in administration, commerce and industry
• Technical Committee: ISO/TC 154 - Processes, data elements and documents in commerce, industry and administration
• Drafting Committee: ISO/TC 154/WG 5 - Representation of dates and times

Relations

• Consolidated By: ISO 15877-5:2009/Amd 2:2020 - Plastics piping systems for hot and cold water installations — Chlorinated poly(vinyl chloride) (PVC-C) — Part 5: Fitness for purpose of the system — Amendment 2
• Effective Date: 06-Jun-2022
• Revises: ISO 8601:2004 - Data elements and interchange formats — Information interchange — Representation of dates and times
• Effective Date: 05-Mar-2016

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 8601-2
First edition
2019-02
Date and time — Representations for
information interchange —
Part 2:
Extensions
Date et heure — Représentations pour l'échange d'information —
Partie 2: Extensions
Reference number
©
ISO 2019
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

Contents Page
Foreword .vii
Introduction .viii
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols and abbreviated terms . 1
3.1 Terms and definitions . 2
3.1.1 Basic concepts . 2
3.1.2 Feature description. 2
3.1.3 Seasons . 4
3.2 Symbols and abbreviated terms. 4
3.2.1 General. 4
3.2.2 Time scale component symbols . 4
3.2.3 Composite component symbols . 5
3.2.4 Symbols used to represent time scale component features . 6
3.2.5 Symbols used in date and time representations . 6
3.2.6 Designator symbols used in date and time expressions . 6
3.2.7 Component symbols, representations and expressions . 7
4 Extensions to time scale components and units . 8
4.1 General . 8
4.2 Order of time scale units. 8
4.3 Additional explicit forms . 8
4.3.1 General. 8
4.3.2 Value prefixing . 8
4.3.3 Calendar day of week . 8
4.3.4 Calendar day of year . 9
4.3.5 Decade . . 9
4.3.6 Century . 9
4.4 Numerical extensions . 9
4.4.1 Negative values . 9
4.4.2 Exponential values .12
4.4.3 Significant digits .13
4.5 Qualification of uncertainty and approximation .13
4.6 Unspecified digits .14
4.6.1 General.14
4.6.2 Unspecified time component value in explicit forms .14
4.6.3 Unspecified time component digits in implicit forms.14
4.7 Expanded calendar year .14
4.7.1 General.14
4.7.2 Letter-prefixed calendar year .15
4.7.3 Exponential calendar year .15
4.7.4 Significant digits .15
4.8 Sub-year groupings .15
4.8.1 Listing of seasons and common sub-year groupings .15
4.8.2 Groupings represented as time scale components.16
4.8.3 Groupings represented as months .16
5 Grouped time scale units .17
5.1 General .17
5.2 Unit definition .17
5.3 Unit value .18
5.4 Application within representations .18
5.4.1 General.18
5.4.2 Use of grouped units .18
5.4.3 Adherence to grouped unit boundaries .20
5.4.4 Representation with time shift .20
5.4.5 Conversion to basic time scale units .20
6 Set representation .21
6.1 Set of date and time expressions .21
6.2 Single element amongst set .21
6.3 Range element expansion .21
6.4 Set representations and expansion .22
6.5 Expressions with time scale components .22
6.6 Integer expressions .22
7 Explicit representation for date and time .23
7.1 General .23
7.2 Date .23
7.2.1 General.23
7.2.2 Calendar date .23
7.2.3 Ordinal date .23
7.2.4 Week date .23
7.3 Time of day .23
7.3.1 Local time of day .23
7.3.2 Beginning of the day .24
7.4 Time shift .24
7.5 Date with shift .25
7.6 Time of day with time shift .25
7.7 Date and time of day .
...