Foreword

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This document was prepared by Technical Committee ISO/TC 59, Buildings and civil engineering works, Subcommittee SC 16, Accessibility and usability of the built environment.

This second edition cancels and replaces the first edition (ISO 21542:2011), which has been technically revised.

The main changes compared to the previous edition are as follows:

a) document structure: a new hierarchy level has been introduced and the clauses have been assigned accordingly and partly resorted (e.g. Clause 5);
b) editorial revision of the Introduction and the Scope;
c) modification of the approach of exceptional considerations, which now only apply to existing buildings;
d) update of the normative references throughout the document;
e) revision of Clause 3 on terms and definitions according to the terminology used in the document and update of the sources;
f) restructuring of several (sub)clauses, especially those on:
1. — orientation and information (5.1);
2. — lighting (5.4);
3. — acoustics (5.7);
4. — paths to the building (6.3);
5. — building entrances and final fire exits (6.5);
6. — vertical and inclined lifting platforms (8.6);
7. — doorsets and windows (9.1);
8. — rooms and space within non-domestic buildings (Clause 10);
g) the provisions regarding tactile walking surface indicators (TWSI) have been adapted:
1. — ISO 23599:2019 has been widely referenced;
2. — a new subclause on tactile walking surface indicators has been introduced to 5.1;
3. — the annex on tactile walking surface indicators was revised and shortened;
h) revision of the provisions regarding visual contrast:
1. — the specifications in 5.3 have been revised and the relevant design factors were moved from the annex on human abilities and associated design considerations to it;
2. — a separate annex for the determination of the luminance contrast has been created;
i) complete revision and enlargement of the specifications on acoustics in 5.7 and emergency warning systems, signals and information in 5.8;
j) clarification and enlargement of the specifications on solitary obstacles in a path in 6.3.8;
k) complete revision of 6.4 on ramps and 8.5 on lifts;
l) enlargement of the specifications on control devices and signals (9.2) and drinking fountains (9.2.9);
m) revision of the clauses related to (fire) emergency evacuation:
1. — merger of the specifications related to (fire) emergency evacuation in Clause 11 but keeping the specifications on emergency warning systems in 5.8, on lifts used for evacuation in 8.5.8 and on fire-resisting doorsets 9.1.2;
2. — introduction of a subclause on emergency evacuation related building infrastructure;
3. — complete revision of the annex on fire prevention, protection, safety and evacuation (Annex D);
n) introduction of a new informative annex on housing (Annex A);
o) editorial revision of existing figures, removal of redundant figures and provision of new figures;
p) update of the Bibliography including the removal of national standards.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

ISO 21542:2021

Building construction. Accessibility and usability of the built environment

Current

Published:

1 Jun 2021