《ISO-9921-2003.pdf》由会员分享，可在线阅读，更多相关《ISO-9921-2003.pdf（36页珍藏版）》请在三一文库上搜索。
1、 Reference number ISO 9921:2003(E) ISO 2003 INTERNATIONAL STANDARD ISO 9921 First edition 2003-10-15 Ergonomics Assessment of speech communication Ergonomie valuation de la communication parle Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=Qa
2、tar Petroleum/5943408001 Not for Resale, 04/12/2007 02:41:00 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO 9921:2003(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shal
3、l not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobes licensing policy. The ISO Central Secretariat accepts no liability in this area.
4、Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by I
5、SO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. ISO 2003 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electroni
6、c or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs 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 copyrightiso.org W
7、eb www.iso.org Published in Switzerland ii ISO 2003 All rights reserved Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=Qatar Petroleum/5943408001 Not for Resale, 04/12/2007 02:41:00 MDTNo reproduction or networking permitted without license f
8、rom IHS -,-,- ISO 9921:2003(E) ISO 2003 All rights reserved iii Contents Page Forewordiv Introduction v 1 Scope1 2 Normative references .1 3 Terms and definitions.1 4 Descriptions of speech communications.3 4.1 General.3 4.2 Speaker 3 4.3 Transmission channel3 4.4 Listener 3 5 Performance of speech
9、communications.3 5.1 General.3 5.2 Alert and warning situations4 5.3 Person-to-person communications 4 5.4 Public address in public areas 4 5.5 Personal communication systems5 5.6 Summary of recommended minimum performance5 6 Assessment and prediction.5 6.1 General.5 6.2 Subjective assessment method
10、s 5 6.3 Objective assessment and prediction methods 6 Annex A (normative) Speaker and listener characteristics .7 Annex B (informative) Subjective speech-intelligibility tests 9 Annex C (informative) Speech transmission index, STI.12 Annex D (informative) Overview of the means of communication and r
11、elated parameters.14 Annex E (normative) Speech interference level, SIL 18 Annex F (informative) Intelligibility ratings for speech communications.19 Annex G (normative) Definition of symbols 22 Annex H (informative) Examples of applications of predictive intelligibility methods .23 Bibliography .28
12、 Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=Qatar Petroleum/5943408001 Not for Resale, 04/12/2007 02:41:00 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO 9921:2003(E) iv ISO 2003 All rights reserved Foreword
13、 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
14、 committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of elec
15、trotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC 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
16、 member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. 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 iden
17、tifying any or all such patent rights. ISO 9921 was prepared by Technical Committee ISO/TC 159, Ergonomics, Subcommittee SC 5, Ergonomics of the physical environment. This first edition of ISO 9921 cancels and replaces ISO 9921-1:1996. Copyright International Organization for Standardization Provide
18、d by IHS under license with ISO Licensee=Qatar Petroleum/5943408001 Not for Resale, 04/12/2007 02:41:00 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO 9921:2003(E) ISO 2003 All rights reserved v Introduction The aim of standardization in the field of the ergonomic asse
19、ssment of speech-communication is to recommend the levels of speech-communication quality required for conveying comprehensive messages in different applications. The quality of speech communication is assessed for the following cases: warning of hazard; warning of danger; information messages for w
20、ork places, public areas, meeting rooms, and auditoria. For some applications, direct communication between humans is considered while, in others, the use of electro-acoustic systems (e.g. PA systems) or personal communication equipment (e.g. telephone, intercom) will be the most convenient means of
21、 informing and instructing or exchanging information. The use of auditory warning symbols other than speech is not included in this International Standard but is covered by ISO 7731. Acoustical danger and warning signals are in general omni-directional and therefore may be universal in many situatio
22、ns. Auditory warnings are of great benefit in situations where smoke, darkness or other obstructions interfere with visual warnings. It is essential that, in the case of verbal messages, a sufficient level of intelligibility is achieved, in the coverage area. If this cannot be achieved, non-voice wa
23、rning signals (see ISO 7731, IEC 60849 and 4 in the Bibliography) or visual warning signals (see ISO 11429) may be preferable. If acoustical signals are too loud, hearing damage or environmental problems may occur (e.g. noise nuisance to dwellings near railway platforms, road traffic, airports, etc.
24、). Good design can minimize these negative aspects. In addition, prediction methods with sufficient accuracy are useful for consultants, suppliers and end- users and may thus reduce costs of necessary adjustments after installation of a system. The communications might be directly between humans, th
25、rough public address or intercom systems or by pre-recorded messages. In general, text-to-speech systems are not recommended because of the low intelligibility of these systems. It is recognized that, in a general-purpose document, simple to apply and easily available tools for prediction and assess
26、ment should be described, as well as more sophisticated advanced technological methodologies. Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=Qatar Petroleum/5943408001 Not for Resale, 04/12/2007 02:41:00 MDTNo reproduction or networking permi
27、tted without license from IHS -,-,- Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=Qatar Petroleum/5943408001 Not for Resale, 04/12/2007 02:41:00 MDTNo reproduction or networking permitted without license from IHS -,-,- INTERNATIONAL STANDARD
28、 ISO 9921:2003(E) ISO 2003 All rights reserved 1 Ergonomics Assessment of speech communication 1 Scope This International Standard specifies the requirements for the performance of speech communication for verbal alert and danger signals, information messages, and speech communication in general. Me
29、thods to predict and to assess the subjective and objective performance in practical applications are described and examples are given. In order to obtain optimal performance in a specific application, three stages can be considered: a) specification of the application and definition of the correspo
30、nding performance criteria; b) design of a communication system and prediction of the performance; c) assessment of the performance for in situ conditions. The use of auditory warning signals other than speech is not included in this International Standard but is covered by ISO 7731. 2 Normative ref
31、erences The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO/TR 4870:1991, Acoustics The construct
32、ion and calibration of speech intelligibility tests IEC 60268-16:1998, Sound system equipment Part 16: Objective rating of speech intelligibility by speech transmission index 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 alarm warning of ex
33、isting or approaching danger 3.2 danger risk of harm or damage 3.3 effective signal-to-noise ratio measure to express the (combined) effect of various types of distortions on the intelligibility of a speech signal in terms of the effect of a masking noise resulting in a speech signal having the same
34、 intelligibility 3.4 emergency imminent risk or serious threat to persons or property Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=Qatar Petroleum/5943408001 Not for Resale, 04/12/2007 02:41:00 MDTNo reproduction or networking permitted wit
35、hout license from IHS -,-,- ISO 9921:2003(E) 2 ISO 2003 All rights reserved 3.5 Lombard effect spontaneous increase of the vocal effort induced by the increase of the ambient noise level at the speakers ear 3.6 non-native speaker person speaking a language which is different from the language that w
36、as learned as the primary language during the childhood of the speaker 3.7 speech communication conveying or exchanging information using speech, speaking, hearing modalities, and understanding NOTE Speech communication may involve brief texts, sentences, groups of words and/or isolated words. 3.8 s
37、peech communicability rating of the ease with which speech communication is performed NOTE Speech communicability includes speech intelligibility, speech quality, vocal effort, and delays. 3.9 speech intelligibility rating of the proportion of speech that is understood NOTE Speech intelligibility is
38、 usually quantified as the percentage of a message understood correctly. 3.10 speech intelligibility index SII objective method for prediction of intelligibility based on the Articulation Index NOTE See 1 in the Bibliography. 3.11 speech interference level SIL difference between A-weighted speech le
39、vel and the arithmetic average of sound-pressure levels of ambient noise in four octave bands with central frequencies of 500 Hz, 1 000 Hz, 2 000 Hz and 4 000 Hz 3.12 speech quality rating of sound quality of a speech signal NOTE Speech quality characterizes the amount of audible distortion of a spe
40、ech signal and is usually rated by a description. 3.13 speech transmission index STI objective method for prediction and measurement of speech intelligibility 3.14 vocal effort exertion of the speaker, quantified objectively by the A-weighted speech level at 1 m distance in front of the mouth and qu
41、alified subjectively by a description Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=Qatar Petroleum/5943408001 Not for Resale, 04/12/2007 02:41:00 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO 9921:2003(E) ISO
42、 2003 All rights reserved 3 3.15 warning important notice concerning any change of status that demands attention or activity 4 Descriptions of speech communications 4.1 General Speech communication requires three sequential components: speaker, transmission channel and listener(s). Based on this con
43、cept, three means of communication are identified. a) Direct communication. This is typical for person-to-person communications, where both persons are in the same environment without making use of electro-acoustic means. b) Public address. In general, an electro-acoustic system that is used to addr
44、ess a group of people in one or more environments. c) Personal communication systems. These include the use of mobile telephones and handheld transceivers and the use of normal telephones, intercoms and hands-free telephones. 4.2 Speaker Several speaker-related parameters define the contribution of
45、the speaker to the performance of a communication. These parameters include vocal effort, speaking quality, gender, accents, non-native speech, speaking disorders, and distance from the listener or microphone. Vocal effort is expressed by the equivalent A-weighted sound-pressure level at a distance
46、of 1 m in front of the mouth. The ambient noise level at the speakers position (causing the Lombard effect) and the wearing of a hearing protector influence the vocal effort. The relation between these parameters and the effect on the speech quality is described in Annex A. The frequency spectrum of
47、 the speech is related to the gender of the speaker and the vocal effort. This may result, in combination with a specific type of noise, in a gender-related performance see Annex B (B.3) and Annex C. The effects of strong accents and non-native speakers and listeners reduce the performance of a comm
48、unication; quantitative data are given in A.6. 4.3 Transmission channel The transmission path between the speakers mouth and the listeners ear is described by the distribution of the speech signal in a room or by an electro-acoustic system. It affects the deterioration of the speech signal. Important influences are ambient noise, reverberation, echoes, sound radiation, limitation in the frequency response, and non-linearities. In Annex D, an overview is given of the means of c