CEN/TS 17551:2021

SLOVENSKI STANDARD
01-april-2021
Vgrajene naprave za gašenje - Avtomatski sprinklerski sistemi - Navodila za
zaščito pred potresi
Fixed firefighting systems - Automatic sprinkler systems - Guidance for earthquake
bracing
Ortsfeste Brandbekämpfungsanlage - Automatische Sprinkleranlagen - Leitfaden für
Erdbebensicherungen
Installations fixes de lutte contre l'incendie - Systèmes d'extinction automatiques du type
sprinkleur - Recommandation pour le contreventement sismique
Ta slovenski standard je istoveten z: CEN/TS 17551:2021
ICS:
13.220.10 Gašenje požara Fire-fighting
91.120.25 Zaščita pred potresi in Seismic and vibration
vibracijami protection
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TS 17551
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
March 2021
TECHNISCHE SPEZIFIKATION
ICS 13.220.20
English Version
Fixed firefighting systems - Automatic sprinkler systems -
Guidance for earthquake bracing
Installations fixes de lutte contre l'incendie - Systèmes Ortsfeste Brandbekämpfungsanlage - Automatische
d'extinction automatiques du type sprinkleur - Sprinkleranlagen - Leitfaden für Erdbebensicherungen
Recommandation pour le contreventement sismique
This Technical Specification (CEN/TS) was approved by CEN on 4 January 2021 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17551:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Design principles . 5
5 Sway bracing and sprinkler pipe support . 6
5.1 General. 6
5.2 Sway brace design. 7
5.3 Anchorage for in rack sprinklers . 23
5.4 Type, attachment and locations of hangers . 24
6 Flexibility . 25
6.1 General. 25
6.2 Flexible Couplings . 26
6.3 Seismic separation assemblies . 27
7 Clearance . 29
7.1 Clearance around piping through walls or floors . 29
7.2 Clearance at sprinklers . 29
8 Other provisions. 29
8.1 Suspended ceilings . 29
8.2 Water supply . 29

European foreword
This document (CEN/TS 17551:2021) has been prepared by Technical Committee CEN/TC 191 “Fixed
firefighting systems”, the secretariat of which is held by BSI.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United
Kingdom.
Introduction
This document specifies requirements for earthquake protection of automatic sprinkler systems in
accordance with EN 12845 and fire hose piping systems. Requirements made herein are intended to
greatly improve the likelihood that the fire protection systems will remain in working condition during
earthquake and minimize or prevent any potential water damage from fixed firefighting systems leakage
due to an earthquake.
1 Scope
This document specifies requirements for earthquake protection of automatic sprinkler systems in
accordance with EN 12845. This document applies only to locations in earthquake zones in accordance
to EN 1998-1:2004, 3.2.1 and for area subject to peak ground acceleration above 9 % of g.
This document does not cover all legislative requirements. In certain countries specific national
regulations apply and take precedence over this document. Users of this document are advised to inform
themselves of the applicability or non-applicability for this document by their national responsible
authorities.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 1998-1:2004, Eurocode 8: Design of structures for earthquake resistance - Part 1: General rules, seismic
actions and rules for buildings
EN 12845, Fixed firefighting systems - Automatic sprinkler systems - Design, installation and maintenance
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 1998-1:2004 and EN 12845
apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
4 Design principles
Requirements given in this document fall into the following seven principles:
— brace sprinkler piping and equipment to minimize uncontrolled differential movement between
these installations and the attached structure; and
— provide flexibility on piping systems and on equipment where differential movement between
portions of those piping systems or equipment is expected; and
— provide clearance between sprinkler piping and structural members, walls, floors or other objects so
that potential damage from impact is minimized; and
— provide anchorage or restraint to minimize potential sliding and/or overturning of equipment such
as the booster pump, jockey pump, tanks, controller, battery package and diesel tank; and
— use types of pipe hangers and sway bracing in accordance to EN 12845 to minimize the potential for
pull-out, properly locate them and attach them to structural members only; and

As impacted by EN 1998-1:2004/AC:2009 and EN 1998-1:2004/A1:2013.
— use types of pipe joining methods in accordance to this document to minimize potential pipe breaks;
and
— provide fire protection system plans and calculations with proper verification of design and proper
verification that the completed installation is in accordance with this document and installed in
accordance with EN 12845.
5 Sway bracing and sprinkler pipe support
5.1 General
Sway bracing for sprinkler systems minimize differential movement between the piping system and the
structure to which it is attached.
Actual design of sway bracing is based on horizontal seismic load. Acceptable sway bracing type,
orientation and attachment methods (to both the sprinkler pipe and the structure) need to
simultaneously provide adequate resistance to both the horizontal seismic load and the net vertical uplift
force component resulting from the horizontal seismic load less any effective offset to that vertical force
component due to sprinkler piping dead weight.
For sprinkler piping within a building, there are two types sway bracing designs two-way and four-way.
Two-way braces are either longitudinal or lateral. Longitudinal and lateral braces resist differential
movement perpendicular and parallel, respectively, to the axis of the pipe, and are used on feed mains,
cross mains, and system range pipes that are DN65 and larger in diameter.

Key
1 two-way brace longitudinal 3 four-way-brace
2 two-way brace lateral
Figure 1 — Sway bracing identification
Four-way sway bracing resists differential movement in all horizontal directions respectively, to the axis
of the pipe, and is typically provided on the above-mentioned items and additionally on risers.
Where lateral and longitudinal sway bracing locations coincide, four-way bracing can be used to satisfy
design requirements for both.
For sway braces to protect the fire sprinkler against damage from earthquakes, their components shall
be shown to have a load capacity greater than the design earthquake load. This requires components to
be cyclical load testing to failure with allowed (design) load rating calculated using a minimum 1,5 safety
factor.
5.2 Sway brace design
5.2.1 Steps in designing sway brace
There are four general steps to properly design sway bracing.
— Step 1: Define sway bracing locations with respect to the sprinkler piping and to the structural
members to which the bracing will be attached.
— Step 2: Calculate the seismic design load requirements for each sway bracing location.
— Step 3: Select the proper sway bracing shape, angle of attachment, size and maximum length based
on the horizontal design load requirement.
— Step 4: Select the proper method to attach the sway bracing to the structure and to the piping.
5.2.2 Step 1, define sway bracing locations
5.2.2.1 Risers
A four-way sway brace shall be provided on all sprinkler risers (whether single or manifolded type)
within 0,6 m of the top of the riser. Brace shall be attached to a structural element for risers located either
on the outside or on the inside of the building. The use of manifolded sway bracing at the top of multiple
adjacent risers requires careful design work and shall be avoided. If used, no more than two risers shall
be used in a manifolded arrangement, and bracing shall be designed to carry the total loads for both risers.
See Figure 2.
Key
1 structural element (given as example- roof 5 0,6 m maximum
could be sloped or flat)
2 roof 6 elbow, flexible joint
3 4-way brace 7 flexible coupling
4 cladding (not structural element)
Figure 2 — Location of 4-ways sway bracing for riser
Intermediate four-way sway bracing shall be provided at an interval (vertical distance) not to exceed
12 m. Where flexible couplings are used, four-way sway bracing shall be provided within 0,6 m of every
other flexible coupling, with
...