Extended application of results from fire resistance tests - Non-loadbearing ceilings - Part 7: Metal sandwich panel construction

This European Standard defines rules for extended applications, provides guidance, and, where appropriate, specifies procedures, for variations of certain parameters and factors associated with the design of internal non-load-bearing ceilings constructed of metal faced sandwich panels that have been tested in accordance with EN 1364-2.
This European Standard applies to self-supporting, double skin metal faced sandwich panels, which have an insulating core bonded to both facings as defined in EN 14509.

Erweiterter Anwendungsbereich der Ergebnisse von Feuerwiderstandsprüfungen - Nichttragende Unterdecken - Teil 7: Sandwichelemente in Metallbauweise

Diese Europäische Norm definiert Regeln für erweiterte Anwendungsbereiche, enthält Leitlinien, und legt, falls erforderlich, Verfahren zur Änderung von bestimmten Parametern und Faktoren fest, die mit der Bauweise von nichttragenden Unterdecken aus Sandwichelementen in Metallbauweise zusammenhängen, die nach EN 1364-2 geprüft wurden und im Innenbereich verwendet werden.
Diese Europäische Norm gilt für selbsttragende Sandwichelemente mit beidseitigen Metalldeckschichten und einem Kern aus Wärmedämmstoff, der auf beiden Seiten verklebt ist, wie in EN 14509 definiert.

Application étendue des résultats d'essais de résistance au feu - Plafonds non porteurs - Partie 7 : Panneaux sandwiches métalliques pour la construction

La présente Norme européenne définit des règles pour des applications étendues, fournit des lignes directrices et, le cas échéant, spécifie des modes opératoires, pour les variations de certains paramètres et facteurs associés à la conception de plafonds intérieurs non porteurs constitués de panneaux sandwich à parements métalliques et soumis à essai conformément à l'EN 1364-2.
La présente Norme européenne s'applique aux panneaux sandwich autoportants double peau à parements métalliques ayant une âme isolante collée aux deux parements, tels que définis dans l'EN 14509.

Razširjena uporaba rezultatov preskusov požarne odpornosti - Nenosilni stropi - 7. del: Konstrukcije iz kovinskih sendvič panelov

Ta evropski standard določa pravila za razširjeno uporabo, podaja navodila in po potrebi določa postopke za odstopanja nekaterih parametrov in dejavnikov, povezanih z obliko notranjih nenosilnih stropov, zgrajenih iz kovinskih sendvič panelov, preskušenih v skladu s standardom EN 1364-2.
Ta evropski standard se uporablja za samonosilne dvoslojne kovinske sendvič panele z izoliranim jedrom, vezanim na obe strani, kot je določeno v standardu EN 14509.

General Information

Status
Published
Public Enquiry End Date
14-Feb-2017
Publication Date
16-May-2018
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
03-May-2018
Due Date
08-Jul-2018
Completion Date
17-May-2018

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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Erweiterter Anwendungsbereich der Ergebnisse von Feuerwiderstandsprüfungen - Nichttragende Unterdecken - Teil 7: Sandwichelemente in MetallbauweiseApplication étendue des résultats d'essais de résistance au feu - Plafonds non porteurs - Partie 7 : Panneaux sandwiches métalliques pour la constructionExtended application of results from fire resistance tests - Non-loadbearing ceilings - Part 7: Metal sandwich panel construction91.060.10Stene. Predelne stene. FasadeWalls. Partitions. Facades13.220.50Požarna odpornost gradbenih materialov in elementovFire-resistance of building materials and elementsICS:Ta slovenski standard je istoveten z:EN 15254-7:2018SIST EN 15254-7:2018en,fr,de01-junij-2018SIST EN 15254-7:2018SLOVENSKI
STANDARDSIST EN 15254-7:20121DGRPHãþD



SIST EN 15254-7:2018



EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 15254-7
April
t r s z ICS
s uä t t rä w râ
{ sä r x rä u r Supersedes EN
s w t w væ yã t r s tEnglish Version
Extended application of results from fire resistance tests æ Nonæloadbearing ceilings æ Part
yã Metal sandwich panel construction Application étendue des résultats d 5essais de résistance au feu æ Plafonds non porteurs æ Partie
y ã Panneaux sandwiches métalliques pour la construction Erweiterter Anwendungsbereich der Ergebnisse von Feuerwiderstandsprüfungen æ Nichttragende Unterdecken æ Teil
yã Sandwichelemente in Metallbauweise This European Standard was approved by CEN on
z January
t r s zä
egulations which stipulate the conditions for giving this European Standard the status of a national standard without any alterationä Upætoædate lists and bibliographical references concerning such national standards may be obtained on application to the CENæCENELEC Management Centre or to any CEN memberä
translation under the responsibility of a CEN member into its own language and notified to the CENæCENELEC Management Centre has the same status as the official versionsä
CEN members are the national standards bodies of Austriaá Belgiumá Bulgariaá Croatiaá Cyprusá Czech Republicá Denmarká Estoniaá Finlandá Former Yugoslav Republic of Macedoniaá Franceá Germanyá Greeceá Hungaryá Icelandá Irelandá Italyá Latviaá Lithuaniaá Luxembourgá Maltaá Netherlandsá Norwayá Polandá Portugalá Romaniaá Serbiaá Slovakiaá Sloveniaá Spainá Swedená Switzerlandá Turkey and United Kingdomä
EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre:
Rue de la Science 23,
B-1040 Brussels
9
t r s z CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Membersä Refä Noä EN
s w t w væ yã t r s z ESIST EN 15254-7:2018



EN 15254-7:2018 (E) 2 Contents Page European foreword . 3 1 Scope . 4 2 Normative references . 4 3 Terms, definitions, symbols and abbreviations . 4 3.1 Terms and definitions . 4 3.2 Symbols and abbreviations . 6 4 Establishing the field of extended application . 6 4.1 General . 6 4.2 Assumptions in the extended application . 7 5 Rules for extended applications of the tested product/construction . 7 5.1 General . 7 5.2 Variations in the materials of the product . 10 5.2.1 General . 10 5.2.2 Variations in the metal sheets . 10 5.2.3 Variations in the adhesive . 11 5.2.4 Variations in the core material . 11 5.3 Variations in the construction . 12 5.3.1 Variations in span length . 12 5.3.2 Variations in the panel thickness . 13 5.3.3 Variations in the longitudinal joint construction . 13 5.3.4 Variations in the boundary conditions and fixing system . 13 5.3.5 Length and width of ceiling construction . 14 5.4 Interaction between the factor influences . 14 5.5 Support structure . 14 5.6 Heating conditions . 14 6 Calculation methods and additional measurements . 15 6.1 Calculation methods . 15 6.1.1 General . 15 6.1.2 Calculation of strength properties . 15 6.2 Additional measurements to be carried out in the reference test . 15 7 Report of the extended application analysis . 15 Annex A (informative)
Typical behaviour of a sandwich panel ceiling when exposed to fire . 17 Annex B (informative)
Typical examples of sandwich panel ceiling end fixings to support structure . 18 Annex C (normative)
Rules and calculation methods for extending the span length of sandwich panel ceilings . 20 C.1 General . 20 C.2 Calculation of allowable span length . 20 C.3 Calculation of catenary force . 21 Bibliography . 23 SIST EN 15254-7:2018



EN 15254-7:2018 (E) 3 European foreword This document (EN 15254-7:2018) has been prepared by Technical Committee CEN/TC 127 “Fire safety in buildings”, the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by October 2018, and conflicting national standards shall be withdrawn at the latest by October 2018. 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. This document supersedes EN 15254-7:2012. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association. This standard is currently composed of the following parts: — EN 15254-2, Extended application of results from fire resistance tests — Non-loadbearing walls — Part 2: Masonry and Gypsum Blocks — EN 15254-4, Extended application of results from fire resistance tests — Non-loadbearing walls — Part 4: Glazed constructions — EN 15254-5, Extended application of results from fire resistance tests — Non-loadbearing walls — Part 5: Metal sandwich panel construction — EN 15254-6, Extended application of results from fire resistance tests - Non-loadbearing walls — Part 6: Curtain walling — EN 15254-7, Extended application of results from fire resistance tests — Non-loadbearing walls — Part 7: Non-load bearing sandwich panels — Ceilings According to the CEN-CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 15254-7:2018



EN 15254-7:2018 (E) 4 1 Scope This document defines rules for extended applications, provides guidance, and, where appropriate, specifies procedures, for variations of certain parameters and factors associated with the design of internal non-loadbearing ceilings constructed of metal faced sandwich panels that have been tested in accordance with EN 1364-2, which could generate a classification in accordance with EN 13501-2. This document applies to self-supporting, double skin metal faced sandwich panels, which have an insulating core bonded to both facings as defined in EN 14509. 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 1363-1, Fire resistance tests — Part 1: General Requirements EN 1363-2, Fire resistance tests — Part 2: Alternative and additional procedures EN 1364-2, Fire resistance tests for non-loadbearing elements — Part 2: Ceilings EN 1993-1-2, Eurocode 3: Design of steel structures — Part 1-2: General rules — Structural fire design EN 13501-2, Fire classification of construction products and building elements — Part 2: Classification using data from fire resistance tests, excluding ventilation services EN 14509, Self-supporting double skin metal faced insulating panels — Factory made products — Specifications EN 15725:2010, Extended application reports on the fire performance of construction products and building elements EN ISO 13943, Fire Safety — Vocabulary (ISO 13943) 3 Terms, definitions, symbols and abbreviations 3.1 Terms and definitions For the purpose of this document, the terms and definitions given in EN 14509, EN 15725, EN 1364-2, EN 1363-1 and EN ISO 13943 the following 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 http://www.iso.org/obp 3.1.1 direct field of application of test results outcome of a process (involving the application of defined rules) whereby a test result is deemed to be equally valid for variations in one or more of the product properties and/or intended end-use applications SIST EN 15254-7:2018



EN 15254-7:2018 (E) 5 3.1.2 extended field of application of test results outcome of a process (involving the application of defined rules that may incorporate calculation procedures) that predicts, for a variation of a product property and/or its intended end-use application(s), a test result on the basis of one or more test results to the same test standard 3.1.3 factor variation that may be applied to a parameter, e.g. a change in the core thickness 3.1.4 factor influence potential cause of a change in the fire resistance when the factor is changed, e.g. an increase in the loadbearing capacity R as a result of an increase in stiffness 3.1.5 fastening, fixing component that fastens the panels to a support structure or to the test frame 3.1.6 fixing system system consisting of fastenings and other possible means used to fasten the panels to a support structure or to the test frame 3.1.7 length of assembly length of the ceiling in the span (or panel length) direction in the reference test or in the end use application 3.1.8 width of assembly width of the ceiling in the cross direction of the span (or panel length) in the reference test or in the end-use application 3.1.9 reference test fire resistance test on which the extended application is based and the results of which are used as the main source of data for the extended application Note 1 to entry: The fire resistance test is in accordance with EN 1363-1 and EN 1364-2, and where applicable EN 1363-2. 3.1.10 stitching component for fixing panels to panels in the longitudinal joint 3.1.11 span length centre to centre distance between two consecutive supports to which the sandwich panel is fixed 3.1.12 support structure construction onto which the panel ceiling is fastened in the end-use application SIST EN 15254-7:2018



EN 15254-7:2018 (E) 6 3.1.13 supporting construction construction that may be required for the testing of some building elements into which the test specimen is assembled 3.1.14 test frame frame containing the test construction for the purpose of mounting onto the furnace 3.2 Symbols and abbreviations For the purposes of this document, the following symbols and abbreviations apply. b width of panel dc depth of core FEd catenary force acting on the fasteners Fv vertical force due to g acting at the fastener FEd1
catenary force acting at the fastener at maximum temperature in the test FEd2
catenary force acting at the fastener at temperature for the increased span Fv1
vertical force due to g acting at the fastener at maximum temperature in the test Fv2
vertical force due to g acting at the fastener at temperature for the increased span g panel weight per square meter L span length n number of fasteners p relative end movement in the fastener T temperature w deflection of the ceiling
linear coefficient of thermal expansion 4 Establishing the field of extended application 4.1 General An extended application analysis is required when the application differs in one or more parameters from the one tested and described in the test report and/or in the classification document, and which is not (fully) covered by the field of direct application of the classification document. Extended application is a prediction of the expected fire resistance of fire resistant metal faced sandwich panels. It may be based on interpolation between or extrapolation from test data. The fundamental consideration shall be that the fire resistant metal faced sandwich panels after extension would achieve the required fire performance if it were to be tested according to EN 1364-2. The extended application of test results from metal faced sandwich panels used as a non-loadbearing ceiling shall be based on the reference fire test results performed according to EN 1364-2 and may be complemented by one or more additional tests. The general rules in EN 15725 shall be followed. SIST EN 15254-7:2018



EN 15254-7:2018 (E) 7 4.2 Assumptions in the extended application The following assumptions are considered when evaluating extended applications for sandwich panels: a) the ceiling is required to provide fire resistance and shall be classified according to EN 13501-2; b) the ceiling is assumed to be exposed on one side (either from above or below) to the standardized heating conditions given in the EN 1363-1 fire resistance test specification or to alternative and additional procedures given in the EN 1363-2; c) the supporting construction to which the ceiling is fixed does not significantly deflect during the fire exposure period; d) after delamination of the fire exposed facing, the dead load of the panels is carried by a support structure to which the ends of the sandwich panels are attached; the forces from the dead load will be distributed to the support structure by the panel fixings from which loadbearing capacity shall be evaluated; e) the support structure has at least the same loadbearing capacity, R, of the fire resistance performance as the sandwich panel ceiling regarding insulation and integrity, if the support structure is on the fire exposed side in end use condition; f) the self weight of the facing and core is calculated from the volume and density of the materials; g) the calculation of the reduction in the strength properties of steel at elevated temperature shall be in accordance with EN 1993-1-2. 5 Rules for extended applications of the tested product/construction 5.1 General When performing extended applications for a tested ceiling, changes can occur either in the materials and/or in the construction. Both are dealt with in this standard. Table 1 and Table 2 list the changes which may or may not be made in an extended application assessment. The rules for the changes are either given in Table 1 or Table 2 or in 5.2 and 5.3. SIST EN 15254-7:2018



EN 15254-7:2018 (E) 8 Table 1 — Material changes relevant to extended application Parameter Factors Factor influence on performance Rules Integrity E Insulation I Changes in metal facings Chemical composition of coating influence no influence a 5.2.2.1 Change from coated to non-coated metal influence influence 5.2.2.1 Sheet thickness influence no influence a Allowed up to ± 0,2 mm of tested thickness Change from one metal to another influence influence 5.2.2.2 Change in sheet geometry influence influence 5.2.2.3 Changes in adhesive Amount influence influence 5.2.3 Type influence no influence a 5.2.3 Changes in core material Type major influence major influence 5.2.4 Change in composition major influence major influence 5.2.4.2 to 5.2.4.6 a It is understood that when a change in a factor can influence the integrity of a joint, there is a possibility that a change in the leakage of hot gases or in joint geometry can also influence the temperature rise near the joint and therefore influence the insulation rating. SIST EN 15254-7:2018



EN 15254-7:2018 (E) 9 Table 2 — Constructional changes relevant to extended application Parameter Factors Factor influence on performance Rules Integrity E Insulation I Span length Decrease no influence no influence Allowed Increase influence no influence a 5.3.1 Panel width Decrease no influence no influence Allowed Increase influence no influence a Test results valid up to + 20 % Panel thickness e.g. core thickness Decrease Increase influence major influence 5.3.2 Joint construction Type major influence major influence 5.3.3 Stitching decreased influence influence Not allowed Stitching increased influence influence 5.3.3 Sealants influence influence 5.3.3 Fixing system Type major influence no influence a 5.3.4 Amount decreased major influence no influence a 5.3.4 Amount increased influence no influence a Allowed Protection decreased major influence influence 5.3.4 Protection increased influence influence Allowed Length of assembly Decrease no influence no influence 5.3.5 Increase influence no influence a 5.3.5 Width of assembly Decrease no influence no influence 5.3.5 Increase no influence no influence 5.3.5 Support structure Changes influence no influence a 5.5 a It is understood that when a change in a factor can influence the integrity of a joint, there is a possibility that a change in the leakage of hot gases or in joint geometry can also influence the temperature rise near the joint and therefore influence the insulation rating. SIST EN 15254-7:2018



EN 15254-7:2018 (E) 10 5.2 Variations in the materials of the product 5.2.1 General Metal faced sandwich panels consist of three main materials: facing metal sheets, adhesive and core material. In the case of auto-adhesively bonded panels, the foamed core material also forms the adhesive layer during the foaming process. Changes in the components of a panel can have influences on the fire resistance. The rules in Clause 5 apply to such changes. 5.2.2 Variations in the metal sheets 5.2.2.1 Variations in the coatings The most essential property of the coating with regard to fire resistance is the emissivity on the unexposed side. Normally the emissivity for a coated steel sheet is between 0,8 and 0,95. A change in emissivity of
« s r % for a new coating compared to the tested one is thus allowed if there is at least a 10 % margin in the insulation test result compared to the I-classification. Test results are always valid for coatings with higher emissivity values compared to the tested one. When a change in coating is made, the manufacturer of the coated sheet shall provide emissivity properties for the products. A non-coated metal sheet can have an emissivity as low as 0,1. A change from a coated to a non-coated sheet is therefore not allowed. The same rule specified above for coatings applies also in this case. A decrease in emissivity of 10 % is allowed if the emissivities of the different sheets are known. The energy content of the coating on the exposed side is small and will not affect the fire resistance properties of the sandwich panel. Test results are valid for all coatings. If modifications in the coatings on the unexposed side are made compared to the tested one, the reaction to fire classification of the product shall be the same or better than the tested one. Test results are valid for all colours of the same type of coating. 5.2.2.2 Variations in the metal material The following rules are valid for extended applications: a) when steel is tested the test results are valid for all grades of steel; b) when stainless steel is tested the test results are valid for all grades of stainless steel; c) for other types of metals, the test result is valid for tested metal type only. NOTE For more information regarding metal faces see EN 14509. 5.2.2.3 Changes in profile geometry of facing The following rules are valid for extended applications: a) Panels with different metal thicknesses on top and bottom sides are regarded as symmetrical if difference in thickness is max. 0,2 mm. b) For panels with flat or small profiling (between 0 mm and 5 mm) on one or both sides test results are valid for any change in the range 0 mm to 5 mm profiling and panels are regarded as symmetrical. This is allowable only if the declared tensile strength value is equal or higher than for the tested panel. SIST EN 15254-7:2018



EN 15254-7:2018 (E) 11 c) For profiles greater than 5 mm test results are valid for profiles with the same moment of inertia within ±10 % as long as dc is not reduced. See Figure 1. a)
e)
b)
f)
c)
g)
d)
Figure 1 — Depth of the core and definition of dc dependent on face geometry (see EN 14509) 5.2.3 Variations in the adhesive This paragraph is valid only for panels with adhesively bonded cores. The following rules apply for an adhesive with no strength at high temperatures (>500 °C) which means that the metal sheet on the exposed side will disconnect from the core in the very beginning of a fire and the construction will lose its sandwich capability. For this reason, an organic adhesive cannot be changed to a non-organic one or vice versa. Normally the energy content of the adhesive is small and will not affect the fire resistance properties of the sandwich panel. The following rules are valid for extended applications. a) For gross calorific potential PCS value of the adhesive
¶ 4 MJ/m2, the results are valid for all adhesives when gross calorific potential PCS value stays below or equal to -4 MJ/m2. b) For gross calorific potential PCS values of the adhesive > 4 MJ/m2, the results are valid for all gross calorific potential PCS values of the adhesive up to 1,15*PCS of the tested one. c) For gross calorific potential PCS value of the adhesive > 4 MJ/m2 and > 1,15*PCS, test results in minutes shall be reduced by the same percentage as the gross calorific potential PCS value is over the initial tested adhesive. 5.2.4 Variations in the core material 5.2.4.1 General Main core materials are defined in EN 14509. The behaviour of these core materials regarding fire is different and cannot be compared. Changes from one core material to another are therefore not allowed. Variations within each core material type are allowed in accordance with the rules given in 5.2.4.2 to 5.2.4.6. There are several factors in the different core materials that affect the fire properties of the core and of the sandwich panel. It is therefore not possible to extend the results from one core material producer to another core material producer. SIST EN 15254-7:2018



EN 15254-7:2018 (E) 12 5.2.4.2 Mineral wool (MW) Generally, the greater the density of the mineral wool the higher is the flexural strength of the panel. Density will be dictated by room-temperature structural design requirements. However, variation in density affects the I-insulation valueä A variation in density is allowed between
« s r % and + 25 % of tested density. Structural design will govern the orientation of fibres i.e. lamellas or slabs used in the panels. Changes in orientation of fibre have an influence on fire resistance and are therefore not allowed. Gaps between the lamellas or ends of lamellas or slabs should be avoided. Test results are valid for panels with a decrease in the number of lamella or slabs joints. The organic content in mass percenatge is governed by room temperature strength of the core. Because variations in organic content can affect the fire resistance properties, the following rules shall be followed: a) A smaller amount of organic content is always allowed compared to the tested one. b) An increase in organic content of 0,5 % percentage points or up to 20 % of tested amount is allowed if the total organic content is below 10 %. For example, a result with 5 % organic content is valid also for a core with 6 % and a result with 2 % for a core with 2,5 %. An increase is not allowed where the organic content is greater than 10 %. The nature and proportions of materials used to manufacture the MW fibres shall not be different from those used in the reference test. 5.2.4.3 Polyurethane (PUR) The test results are valid for the same chemical system and blowing agent. The test results are valid for ± 10 % of tested density. 5.2.4.4 Extruded polystyrene (XPS) and expanded polystyrene (EPS) No extended application is allowed. 5.2.4.5 Phenolic foam (PF) The test results are valid for the same chemical system and blowing agent. The test results are valid for ± 10 % of tested density. 5.2.4.6 Cellular glass (CG) No extended application is allowed. 5.3 Variations in the construction 5.3.1 Variations in span length Two aspects of fire integrity shall be assessed. The first aspect shall be the ability of the whole panel assembly to resist collapse when the adhesive bond fails on the exposed side and the panels lose their flexural strength. To resist collapse, the ends of the panel facings shall be secured to the structure using suspension details (e.g. steel cleats with fastenings). Properly designed ceilings shall have both facings mechanically fastened (see typical solutions in Annex B) so they cannot collapse before the support structure collapses (see 5.5). The strength of these suspension details shall be able to carry the dead loads at the temperatures they attain from an increased load of a longer span panel. This can be achieved by increasing the amount of fixings based on the rules and calculation method given in Annex C. SIST EN 15254-7:2018



EN 15254-7:2018 (E) 13 The second aspect of integrity to be assessed shall be the ability of joints between adjoining sandwich panels to resist the passage of fire. This can be handled by limiting the allowable deflection to be the same as the maximum deflection at failure in the test. The rules and calculation method are given in Annex C. To be able to do an extension in the span length there shal
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