ISO INTERNATIONAL STANDARD 389-7 Third edition 2019-10 Acoustics Reference zero for the calibration of audiometric equipment - Part 7: Reference threshold of hearing under free-field and diffuse-field listening conditions Acoustique - Zéro de reference pour I'étalonnage d'équipements audiométriques- Partie 7: Niveau liminaire de réference dans des conditions d'écoute en champ libre et en champ diffus Reference number ISO 389-7:2019(E) ISO @ IS0 2019 IS0 389-7:2019(E) COPYRIGHTPROTECTEDDOCUMENT @ IS0 2019 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may 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 Fax: +41 22 749 09 47 Email: copyright@iso.org Website: www.iso.org Published in Switzerland ii @ IS0 2019 - All rights reserved