ISO INTERNATIONAL STANDARD 21925-2 First edition 2021-06 Fire resistance tests Fire dampers for air distribution systems Part 2: Intumescent dampers Essais de résistance au feu - Clapets résistant au feu pour des systemes de distribution d'air- Partie 2: Clapets intumescents Reference number IS0 21925-2:2021(E) ISO @ISO2021 IS0 21925-2:2021(E) COPYRIGHTPROTECTED DOCUMENT IS02021 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: +41 22 749 01 11 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0 2021 - All rights reserved