ISO INTERNATIONAL STANDARD 15619 First edition 2013-10-01 Reciprocating internal combustion engines Measurement method for exhaust silencers Sound power level of exhaust noise and insertion loss using sound pressure and power loss ratio Moteurs alternatifs a combustion interne - Méthode de mesure pour silencieux d'échappement - Niveau de puissance acoustique du bruit a I'échappement et perte par insertion a partir de la pression acoustique et du rapport de perte de puissance Reference number ISO 15619:2013(E) ISO @ IS0 2013 I without license from IHS Not for Resale IS0 15619:2013(E) COPYRIGHT PROTECTED DOCUMENT @IS02013 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form 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 Case postale 56 : CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail [email protected] Web www.iso.org Published in Switzerland @ IS0 2013 - All rights reserved No reproduction or networking permited without license from IHS Not for Resale IS0 15619:2013(E) Contents Page Foreword ..iv Introduction. .. 1 Scope. 1.1 Measurement uncertainty 2 Normative references ..2 3 Terms and definitions ..2 4 Test environment. .6 4.1 General .6 4.2 Criteria for background noise. ..7 4.3 Criterion for acoustic adequacy of test environment ..9 5 Instrumentation. ..10 5.1 General. .10 5.2 Calibration 10 6 Installation and operation of noise source under test for laboratory measurement. .10 6.1 General 10 6.2 Source location 11 6.3 Installationrequirements ..11 6.4 Operation condition. ..13 7 Measurement .13 7.1 General, ..13 7.2 Laboratory measurement .14 7.3 Site measurement. ..17 8 Calculation .20 8.1 General. 20 8.2 Calculation of sound power level of exhaust noise 20 8.3 Calculation of insertion loss 22 8.4 Calculation of power loss ratio. 23 9 Information to be recorded .23 9.1 General 23 9.2 Description of the tested exhaust silencer and substitution pipe 23 9.3 Description of the engine on which the exhaust silencer is installed. .23 9.4 Acousticenvironment 23 9.5 Description of instrumentation 23 9.6 Acousticaldata .23 10 Test report ..24 Annex A (normative) Qualification procedures for the acoustic environment. ..25 Annex B (informative) Measurement procedure for pressure loss.. .30 Annex C (normative) Calculation of A-weighted sound power levels from frequency band levels ..31 Annex D (normative) Sound power level under reference meteorological conditions .33 Bibliography ..35 ii e with IS ed without license from IHS Not for Resale