ISO INTERNATIONAL STANDARD 20906 First edition 2009-12-15 Acoustics Unattended monitoring of aircraft sound in the vicinity of airports Acoustique - Surveillance automatique du bruit des aéronefs au voisinage des aéroports Reference number ISO 20906:2009(E) @ ISO 2009 Tby IHS under lic ted without license from IHS Not for Resale ISO 20906:2009(E) Contents Page Foreword Introduction 1 Scope 2 Normative references. 3 Terms and definitions 4 Data acquisition .... 4.1 Instruments and equipment . 4.2 Microphone mounting.... 4.3 Preferred measured quantities ..... 4.4 Time stamp... 10 4.5 Aircraft sound event detection and classification ... 10 4.6 11 4.7 Transmission of data .. 11 4.8 Acoustical calibration and verification 4.9 Environmental characteristics .. 13 4.10 Measurement of meteorological conditions. 14 5 Data processing.. 14 5.1 General... .14 5.2 Basic requirements .. 14 5.3 Aircraft sound event data... 15 5.4 Event identification .... 5.5 Incomplete or corrupted data... 17 5.6 Total sound and residual sound ... 18 5.7 Data storage...... 18 6 Measurement uncertainty .... 19 7 Reporting of data... .19 7.1 7.2 Reporting of aircraft sound event data .. .19 7.3 Environmental reports..... 21 8 Instruction manual 21 Annex A (informative) Selection of sites for sound monitors .... .23 Annex B (informative) Uncertainty of reported data . 27 Bibliography... 36 Copyright International Organizaion for Standardizalon'ghts reserved ii Not for Resale ISO 20906:2009(E) Foreword IsO (the International Organization for Standardization) is a worldwide federation of national standards bodies (isO member bodies). The work of preparing International Standards is normally carried out through IsO technical committees. Each member body interested in a subject for which a technical committee has beer International Standards are drafted in accordance with the rules given in the ISO/lEc Directives, Part 2 The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. IsO shall not be held responsible for identifying any or all such patent rights. ISO 20906 was prepared by Technical Committee ISO/TC 43, Acoustics, Subcommittee SC 1, Noise. Iso 2009-All rights reserved ional Organization for Standardization Not for Resale