ISO INTERNATIONAL STANDARD 11957 First edition 1996-12-01 Acoustics -- Determination of sound insulation performance of cabins Laboratory and in situ measurements Acoustique Determination des performances d'isolation acoustique des cabines - Mesurages en laboratoire et in situ This material is reproduced from ISo documents under International Organization for Standardization (Iso) Copyright License number IHS/ICC/1996. Not for resale. No part of these ISO documents may be reproduced in any form, electronic retrieval system or otherwise, except as allowed in the copyright law of the country of use, or with the prior written consent of 1so (Case postale 56, 1211 Geneva 20, Switzerland, Fax +4122734 10 79),IHS or the ISo Licensor'smembers. Reference number ISO11957:1996(E) No reproduction or networking permited without license from IHS Not for Resale ISO 11957:1996(E) Contents Page Scope 2 Normative references 1 3 Definitions... 1 4 Test environment and choice of suitable quantity 2 5 Instrumentation. 3 6 Measurement of sound insulation performance in the laboratory.. 3 6.1 General... 3 6.2 Cabinlocation. 3 6.3 Cabin mounting and conditions. 3 6.4 Measurement of the sound pressure level in the room ... 4 6.5 Measurement ofthe sound pressure fevel inside the cabin 4 6.6 Sound pressure insulation, D, 4 6.7 Measurement of noise inside the cabin due to noise sources forming an integral part of the cabin (internal 5 Measurement of sound insulation performance in situ.. 5 7.1 General.. 5 7.2 External sound field .. 5 7.3 Cabin mounting and conditions 6 7.4 Microphone positions in the room.. 9 7.5 Microphone positions inside the cabin. 6 7.6 Apparentsoundpressureinsulation,D' 6 7.7 Measurement of noise inside the cabin due to noise sources forming an integral part of the cabin (internal noise level, Lp......... ISO1996 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced microfilm,without permission in writing from the publisher. International Organization for Standardization Case Postale 56.CH-1211 Geneve 20.Switzerland Printed in Switzerland i from IHS Not for Resale ISO 11957:1996(E) @ISO 8 Weighted sound pressure insulation... 7 9 Estimated cabin noise insulation for a specific noise spectrum.... 7 10 Uncertainty... 7 11 Information to be recorded. 7 11.1 Test object. 7 11.2 Test conditions . 8 11.3 Instrumentation. 8 11.4 Acoustical data ... 8 11.5 Further information 8 12 Information to be reported, 8 Annexes A Estimated cabin noise insulation for a specific noise spectrum.... 10 B Bibliography 11 ili No reproduction or networking permitted with Not for Resale