ETSI ES 202 076 V2.1.1 (2009-08)

ETSI ES 202 076 V2.1.1 (2009-08)
ETSI Standard
Human Factors (HF);
User Interfaces;
Generic spoken command vocabulary
for ICT devices and services
---------------------- Page: 1 ----------------------
2 ETSI ES 202 076 V2.1.1 (2009-08)
Reference
RES/HF-00081
Keywords
ICT, interface, speech, telephony, voice, user
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE
Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16
Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88
Important notice
Individual copies of the present document can be downloaded from:
http://www.etsi.org

The present document may be made available in more than one electronic version or in print. In any case of existing or

perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF).

In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive

Users of the present document should be aware that the document may be subject to revision or change of status.

Information on the current status of this and other ETSI documents is available at

If you find errors in the present document, please send your comment to one of the following services:

DECT , PLUGTESTS , UMTS , TIPHON , the TIPHON logo and the ETSI logo are Trade Marks of ETSI registered

3GPP is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners.

GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association.

Intellectual Property Rights ................................................................................................................................ 4

Foreword ............................................................................................................................................................. 4

Introduction ........................................................................................................................................................ 4

1 Scope ........................................................................................................................................................ 6

2 References ................................................................................................................................................ 6

2.1 Normative references ......................................................................................................................................... 6

2.2 Informative references ........................................................................................................................................ 7

3 Definitions and abbreviations ................................................................................................................... 7

3.1 Definitions .......................................................................................................................................................... 7

3.2 Abbreviations ..................................................................................................................................................... 8

4 User requirements .................................................................................................................................... 8

5 Method ..................................................................................................................................................... 9

5.1 General ............................................................................................................................................................... 9

5.2 Elicitation of command candidates..................................................................................................................... 9

5.3 Validation of command candidates .................................................................................................................. 10

5.4 Phonetic discriminability .................................................................................................................................. 10

5.5 Final command definition ................................................................................................................................ 10

6 List of commands ................................................................................................................................... 11

6.1 Principles of use ............................................................................................................................................... 11

6.2 Basic commands ............................................................................................................................................... 12

6.3 Digits ................................................................................................................................................................ 17

6.4 Communication commands .............................................................................................................................. 20

6.5 Commands for the control of and navigation in media .................................................................................... 27

6.6 Commands for device and service settings ....................................................................................................... 33

Annex A (informative): Methodology for defining command vocabularies ...................................... 40

A.1 Elicitation: the spontaneous generation of potential command words ................................................... 40

A.1.1 Interviewers ...................................................................................................................................................... 41

A.1.2 Test participants ............................................................................................................................................... 41

A.1.3 Set of functions ................................................................................................................................................. 41

A.1.4 Carefully Worded Descriptions (CWDs) ......................................................................................................... 41

A.1.5 Interviews ......................................................................................................................................................... 42

A.1.6 Data Cleaning ................................................................................................................................................... 42

A.1.7 Frequency Analysis .......................................................................................................................................... 42

A.2 Validation ............................................................................................................................................... 42

A.3 Phonetic discriminability ........................................................................................................................ 43

A.4 Final command definition ...................................................................................................................... 44

Annex B (informative): Bibliography ................................................................................................... 45

History .............................................................................................................................................................. 46

IPRs essential or potentially essential to the present document may have been declared to ETSI. The information

pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found

in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in

respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web

Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee

can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web

This ETSI Standard (ES) has been produced by ETSI Technical Committee Human Factors (HF).

The work has been conducted in collaboration with industry. The present document is based upon user testing,

empirical data, phonetic discriminability analysis, expert knowledge, and an industry-consultation and consensus

process, aimed at a quick uptake and the widest possible support in product implementations to come.

Telecommunications, converging with information processing, and intersecting with mobility and the internet, are

leading to the development of new interactive applications and services, offering global access.

A technology enabling a natural user interaction with these (often complex) systems and services is speech recognition.

In recent years, speech recognition has become commercially viable in off-the-shelf ICT (Information and

Communication Technology) devices and services. Just as the graphical user interface changed the way we interact with

personal computers, so voice user interfaces are changing the way we interact with ICT devices and services.

Voice is fundamental to human communication and forms an important channel for universal access to ICT services.

Voice user interfaces are a terminal, display and potentially location-independent user interface technology, enabled by

speech recognition technologies. In order to simplify the user's learning and facilitate reuse of knowledge for the control

of different applications and devices, it is desirable to standardize voice commands for the most common and generic

functions. This standardization activity also meets one of the most important principles of the eEurope 2005 Action

Plan; that of design for all. This theme has been continued by the new EU initiative; the i2010 Action Plan. This will

help ensure that those with special needs such as elderly people, people with visual and other impairments, as well as

young children will benefit from a generic spoken command vocabulary. As the standard necessarily addresses speech

input it is recommended that the users of the present document provide some form of guidance for those end users who

The present document is a timely contribution to enable the deployment of speech recognition in services and devices,

offering multi-lingual voice user interfaces. Thereby it will minimize learning effort, facilitate knowledge transfer and

develop user trust. Uniformity in the basic spoken commands improves the overall usability of the entire interactive

environment, which becomes increasingly important in a world of ubiquitous devices and services using speech

The minimum generic set of spoken commands in the present document has been developed with a combined

methodology, including the collection of data from native speakers of the 30 languages covered by the present

document (see annex A for details). Therefore, it supports developers of ICT devices and services, leading to quicker,

The work is aligned with, and co-funded by, the European Commission's initiative eEurope, a programme for inclusive

deployment of new, important, consumer-oriented technologies, opening up global access to communications and other

The present document specifies a minimum set of spoken commands required to control the generic and common

functions of ICT devices and services that use speaker-independent speech recognition. It specifies the necessary and

most common vocabularies for voice commands to be supported by ICT devices and services.

The present document is applicable to the functions required for user interface navigation, call handling, the control of

The present document specifies commands for the official languages (at the time of publication) of the European Union

(EU) and the European Free Trade Association (EFTA) countries, and for Russian. The standard addresses Bulgarian,

Croatian, Czech, Danish, Dutch, English, Estonian, Finnish, French, German, Greek, Hungarian, Icelandic, Irish,

Italian, Latvian, Lithuanian, Macedonian, Maltese, Norwegian, Polish, Portuguese, Raeto-Romance, Romanian,

Russian, Slovak, Slovene, Spanish, Swedish, and Turkish [4]. Therefore, this updates the existing standard,

ES 202 076 [1], which covers only the five languages with the largest number of native speakers in the European

Union: English, French, German, Italian and Spanish. The present document does not cover dialects with the exception

of Norwegian and Raeto Romance both of which have established dialects. All languages are addressed in "Received

The present document does not cover dialogue design issues, the full range of supplementary telecommunications

services, performance-related issues or speech output. Alphanumeric characters and symbols are not covered with the

exception of single digits and language-specific reference to two recurring digits (e.g. "Double Two").

References are either specific (identified by date of publication and/or edition number or version number) or

• Non-specific reference may be made only to a complete document or a part thereof and only in the following

- if it is accepted that it will be possible to use all future changes of the referenced document for the

Referenced documents which are not found to be publicly available in the expected location might be found at

NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee

The following referenced documents are indispensable for the application of the present document. For dated

references, only the edition cited applies. For non-specific references, the latest edition of the referenced document

[1] ETSI ES 202 076 (V1.1.2): "Human Factors (HF) ; User Interfaces; Generic spoken command

NOTE: Available at http://ec.europa.eu/information_society/eeurope/i2010/index_en.htm.

[3] ITU-T Recommendation I.210 (1993): "principles of telecommunications services supported by an

NOTE: Available at http://ec.europa.eu/education/policies/lang/languages/index_en.html.

[5] ISO 9241-11 (1998): "Ergonomic requirements for office work with visual display terminals

The following referenced documents are not essential to the use of the present document but they assist the user with

regard to a particular subject area. For non-specific references, the latest version of the referenced document (including

[i.1] ETSI EG 201 013: "Human Factors (HF); Definitions, abbreviations and symbols".

[i.2] ETSI TR 102 068: "Human Factors (HF); Requirements for assistive technology devices in ICT".

[i.3] ETSI EG 202 048: "Human Factors (HF); Guidelines on the multimodality of icons, symbols and

For the purposes of the present document, the terms and definitions given in EG 201 013 [i.1] and the following apply:

design for all: design of products to be usable by all people, to the greatest extent possible, without the need for

function: abstract concept of a particular use of or operation in a device or service

ICT devices and services: devices or services for processing information and/or supporting communication, which

impairment: reduction or loss of psychological, physiological or anatomical function or structure of a user

keyword: word that the speech recognition system is looking for in word spotting mode

NOTE: A menu dialogue offers a user a series of lists of choices from which a series of selections can be made.

phonetic discriminability: ability to discriminate between words based on the analysis of their constituent phones

spoken command: verbal or other auditory dialogue format which enables the user to input commands to control a

supplementary service: additional service that modifies or supplements a basic telecommunication service

NOTE: Consequently, it cannot be offered to a customer as a stand-alone service; it has to be offered in

association with a basic telecommunication service. The same supplementary service may be common to

a number of basic telecommunication services. See ITU-T Recommendation I.210 [3].

usability: effectiveness, efficiency and satisfaction with which specified users achieve specified goals in particular

user interface: elements of a product used to control it and receive information about its status, and the interaction that

user requirements: requirements made by users, based on their needs and capabilities, in order to make use of a

word spotting mode: special state of the recognition system in which no speech is recognized or processed other than a

NOTE: A typical usage is in a dormant state of the speech recognizer, where issuing a "wake up" command (also

Intended users of the present document are those designing, developing, implementing and deploying ICT devices and

Intended end users mentioned in the present document are people who use ICT devices and services with a speech

Uniformity in the interactive elements increases the transfer of learning between different devices and services. Such

knowledge transfer becomes even more important in a world of ubiquitous devices and services using speech

recognition technology. In particular standardized commands improve the overall usability of the entire interactive

environment. Use of the generic vocabulary of spoken commands in the present document for the development of ICT

A generic spoken command vocabulary will particularly benefit some end users with temporary or permanent additional

needs, such as those with literacy difficulties, people with visual or cognitive impairments, those with an impaired

For further guidance, including specifics of user impairments and resulting disabilities, assistive technologies, design

Ideally, a spoken command vocabulary should be intuitive, easy to learn, memorable, natural, and unambiguous. A

• the ability to handle the vagaries of speech recognizers in a reliable and predictable way, maximizing the user

Adequate feedback should be provided to users indicating, where applicable, that a command cannot be executed when

In order to meet the requirements stated in clause 4, where the standard is designed for a wide range of end users, an

empirical method has been employed for the elicitation and validation of potential voice commands. Native speakers of

the 30 languages were sampled for this data collection. The previous standard used an online method of data collection

where respondents were asked to complete a questionnaire. This worked well for the five most frequently spoken

languages of the EU. However, the extension of the standard covers countries where internet penetration is relatively

low and online questionnaires for these countries would not yield a representative sample of users for the purposes of

In addition to elicitation and validation, a procedure of phonetic discriminability has been applied to the candidate

commands to ensure minimal confusion with commands that are likely to be simultaneously available.

These phases are outlined here. More detailed descriptions of each phase can be found in annex A.

In this phase, a sample of native speakers representing three age groups, aiming for an equal distribution of men and

women, were invited to take part in an interview on voice commands. At this stage, they were given some general

background to the aims of the study in order to inform them of the aims of the study prior to gaining their consent to

participating in the research. In most cases the interview was conducted by telephone but, in a small number of cases, an

interview was conducted with interviewer and interviewee sitting back to back in order to prevent artefacts based on the

interviewer's reactions. The interviewer, or Native Language Assistant (NLA), was also always a native or near-native

speaker who also carried out translations and transcriptions from documents in the original English and conducted

analyses. They read out, for each command, a phrase describing the function of the device or service, known as the

Carefully Worded Description (CWD), without mentioning any of the most likely resulting terms. The interviewees

were then asked to name the term or terms they would find most suitable as a command in the context of a spoken-

EXAMPLE: The carefully worded description used for describing the supplementary service "Call deflection"

was: "You hear the phone ring at a time when you do not want to speak to anyone. You want the

connection to be passed on to another name or number instead. What command would you give

From this process a number of different alternative command candidates were collected. The lists of terms were then

processed in order to reduce the number of morphological forms, e.g. infinitive or imperative, singular or plural, formal

or informal addressing. The data were also checked for typological errors and answers which did not reflect the function

implied by the carefully worded descriptions. The resulting terms were ordered according to the percentage of

participants who had named them, and the most frequently chosen terms were used as input to the validation phase.

In identifying the appropriate spoken commands it is not sufficient to conduct elicitation alone. It was also necessary to

rank the proposed terms in order to provide a degree of validation. Therefore, validation interviews were set up and

carried out in a similar way to elicitation interviews where the candidate commands were ranked in order of preference

by the participants (see clause A.2). The top-ranked commands were then put forward to the phonetic discriminability

The method described here was applied to the majority of the languages. However, it became clear that this method

was an unnecessary use of resources as the same result could be obtained by subjecting the results from discrimination

to expert analysis. Therefore, (see clause A.2), expert analysis was applied to those languages which had not undergone

validation, namely: Estonian, Greek, Icelandic, Latvian, Maltese, Norwegian, Portuguese, Raeto-Romance, Swedish,

and Turkish to identify the spoken commands which were chosen for phase 3, phonetic discriminability. The experts

comprised a combination of: the NLAs, industry experts, linguistic and cultural representatives from the countries

Whilst the previous two steps have provided a user-centric approach to the selection of command words, it is still

EXAMPLE: A selection of words may be chosen as a result of the previous two phases that have a high level of

However, if this selection gives rise to a high degree of confusability in the speech recognizer, between words which are

available for use in the same context, then the overall goal of usability is nullified. Therefore, discriminability analysis

was carried out to ensure that command words that are likely to be active simultaneously in a dialogue context can be

a) Commands were clustered according to those which would be simultaneously available, e.g. all commands for

b) For each context, the top three commands from validation were assessed by native-language experts with

respect to their sounds and not to their orthographic forms. Commands were listed as potentially phonetically

d) An alternative for one of the command words was chosen, with minimum repercussion with respect to the

The final pass on the resulting command set was performed by submitting the results to a number of different groups for

• Educated native speakers to ensure consistency within the entire language set in terms of morphological and

• Cultural and linguistic institutes of each of the languages represented in the standard.

• The industry reference group. This is a body of experts from industry, such as service providers and handset

manufacturers, who would be responsible for the implementation of the standard in some or all of the countries

Final draft ETSI ES 202 076 V2.1.1 (2009-06)
ETSI Standard
Human Factors (HF);
User Interfaces;
Generic spoken command vocabulary
for ICT devices and services
---------------------- Page: 1 ----------------------
2 Final draft ETSI ES 202 076 V2.1.1 (2009-06)
Reference
RES/HF-00081
Keywords
ICT, interface, speech, telephony, voice, user
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE
Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16
Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88
Important notice
Individual copies of the present document can be downloaded from:
http://www.etsi.org

The present document may be made available in more than one electronic version or in print. In any case of existing or

perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF).

In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive

Users of the present document should be aware that the document may be subject to revision or change of status.

Information on the current status of this and other ETSI documents is available at

If you find errors in the present document, please send your comment to one of the following services:

DECT , PLUGTESTS , UMTS , TIPHON , the TIPHON logo and the ETSI logo are Trade Marks of ETSI registered

3GPP is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners.

GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association.

Intellectual Property Rights ................................................................................................................................ 4

Foreword ............................................................................................................................................................. 4

Introduction ........................................................................................................................................................ 4

1 Scope ........................................................................................................................................................ 6

2 References ................................................................................................................................................ 6

2.1 Normative references ......................................................................................................................................... 6

2.2 Informative references ........................................................................................................................................ 7

3 Definitions and abbreviations ................................................................................................................... 7

3.1 Definitions .......................................................................................................................................................... 7

3.2 Abbreviations ..................................................................................................................................................... 8

4 User requirements .................................................................................................................................... 8

5 Method ..................................................................................................................................................... 9

5.1 General ............................................................................................................................................................... 9

5.2 Elicitation of command candidates..................................................................................................................... 9

5.3 Validation of command candidates .................................................................................................................. 10

5.4 Phonetic discriminability .................................................................................................................................. 10

5.5 Final command definition ................................................................................................................................ 10

6 List of commands ................................................................................................................................... 11

6.1 Principles of use ............................................................................................................................................... 11

6.2 Basic commands ............................................................................................................................................... 12

6.3 Digits ................................................................................................................................................................ 17

6.4 Communication commands .............................................................................................................................. 20

6.5 Commands for the control of and navigation in media .................................................................................... 27

6.6 Commands for device and service settings ....................................................................................................... 33

Annex A (informative): Methodology for defining command vocabularies ...................................... 40

A.1 Elicitation: the spontaneous generation of potential command words ................................................... 40

A.1.1 Interviewers ...................................................................................................................................................... 41

A.1.2 Test participants ............................................................................................................................................... 41

A.1.3 Set of functions ................................................................................................................................................. 41

A.1.4 Carefully Worded Descriptions (CWDs) ......................................................................................................... 41

A.1.5 Interviews ......................................................................................................................................................... 42

A.1.6 Data Cleaning ................................................................................................................................................... 42

A.1.7 Frequency Analysis .......................................................................................................................................... 42

A.2 Validation ............................................................................................................................................... 42

A.3 Phonetic discriminability ........................................................................................................................ 43

A.4 Final command definition ...................................................................................................................... 44

Annex B (informative): Bibliography ................................................................................................... 45

History .............................................................................................................................................................. 46

IPRs essential or potentially essential to the present document may have been declared to ETSI. The information

pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found

in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in

respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web

Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee

can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web

This ETSI Standard (ES) has been produced by ETSI Technical Committee Human Factors (HF), and is now submitted

The work has been conducted in collaboration with industry. The present document is based upon user testing,

empirical data, phonetic discriminability analysis, expert knowledge, and an industry-consultation and consensus

process, aimed at a quick uptake and the widest possible support in product implementations to come.

Telecommunications, converging with information processing, and intersecting with mobility and the internet, are

leading to the development of new interactive applications and services, offering global access.

A technology enabling a natural user interaction with these (often complex) systems and services is speech recognition.

In recent years, speech recognition has become commercially viable in off-the-shelf ICT (Information and

Communication Technology) devices and services. Just as the graphical user interface changed the way we interact with

personal computers, so voice user interfaces are changing the way we interact with ICT devices and services.

Voice is fundamental to human communication and forms an important channel for universal access to ICT services.

Voice user interfaces are a terminal, display and potentially location-independent user interface technology, enabled by

speech recognition technologies. In order to simplify the user's learning and facilitate reuse of knowledge for the control

of different applications and devices, it is desirable to standardize voice commands for the most common and generic

functions. This standardization activity also meets one of the most important principles of the eEurope 2005 Action

Plan; that of design for all. This theme has been continued by the new EU initiative; the i2010 Action Plan. This will

help ensure that those with special needs such as elderly people, people with visual and other impairments, as well as

young children will benefit from a generic spoken command vocabulary. As the standard necessarily addresses speech

input it is recommended that the users of the present document provide some form of guidance for those end users who

The present document is a timely contribution to enable the deployment of speech recognition in services and devices,

offering multi-lingual voice user interfaces. Thereby it will minimize learning effort, facilitate knowledge transfer and

develop user trust. Uniformity in the basic spoken commands improves the overall usability of the entire interactive

environment, which becomes increasingly important in a world of ubiquitous devices and services using speech

The minimum generic set of spoken commands in the present document has been developed with a combined

methodology, including the collection of data from native speakers of the 30 languages covered by the present

document (see annex A for details). Therefore, it supports developers of ICT devices and services, leading to quicker,

The work is aligned with, and co-funded by, the European Commission's initiative eEurope, a programme for inclusive

deployment of new, important, consumer-oriented technologies, opening up global access to communications and other

The present document specifies a minimum set of spoken commands required to control the generic and common

functions of ICT devices and services that use speaker-independent speech recognition. It specifies the necessary and

most common vocabularies for voice commands to be supported by ICT devices and services.

The present document is applicable to the functions required for user interface navigation, call handling, the control of

The present document specifies commands for the official languages (at the time of publication) of the European Union

(EU) and the European Free Trade Association (EFTA) countries, and for Russian. The standard addresses Bulgarian,

Croatian, Czech, Danish, Dutch, English, Estonian, Finnish, French, German, Greek, Hungarian, Icelandic, Irish,

Italian, Latvian, Lithuanian, Macedonian, Maltese, Norwegian, Polish, Portuguese, Raeto-Romance, Romanian,

Russian, Slovak, Slovene, Spanish, Swedish, and Turkish [4]. Therefore, this updates the existing standard,

ES 202 076 [1], which covers only the five languages with the largest number of native speakers in the European

Union: English, French, German, Italian and Spanish. The present document does not cover dialects with the exception

of Norwegian and Raeto Romance both of which have established dialects. All languages are addressed in "Received

The present document does not cover dialogue design issues, the full range of supplementary telecommunications

services, performance-related issues or speech output. Alphanumeric characters and symbols are not covered with the

exception of single digits and language-specific reference to two recurring digits (e.g. "Double Two").

References are either specific (identified by date of publication and/or edition number or version number) or

• Non-specific reference may be made only to a complete document or a part thereof and only in the following

- if it is accepted that it will be possible to use all future changes of the referenced document for the

Referenced documents which are not found to be publicly available in the expected location might be found at

NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee

The following referenced documents are indispensable for the application of the present document. For dated

references, only the edition cited applies. For non-specific references, the latest edition of the referenced document

[1] ETSI ES 202 076 (V1.1.2): "Human Factors (HF) ; User Interfaces; Generic spoken command

NOTE: Available at http://ec.europa.eu/information_society/eeurope/i2010/index_en.htm.

[3] ITU-T Recommendation I.210 (1993): "principles of telecommunications services supported by an

NOTE: Available at http://ec.europa.eu/education/policies/lang/languages/index_en.html.

[5] ISO 9241-11 (1998): "Ergonomic requirements for office work with visual display terminals

The following referenced documents are not essential to the use of the present document but they assist the user with

regard to a particular subject area. For non-specific references, the latest version of the referenced document (including

[i.1] ETSI EG 201 013: "Human Factors (HF); Definitions, abbreviations and symbols".

[i.2] ETSI TR 102 068: "Human Factors (HF); Requirements for assistive technology devices in ICT".

[i.3] ETSI EG 202 048: "Human Factors (HF); Guidelines on the multimodality of icons, symbols and

For the purposes of the present document, the terms and definitions given in EG 201 013 [i.1] and the following apply:

design for all: design of products to be usable by all people, to the greatest extent possible, without the need for

function: abstract concept of a particular use of or operation in a device or service

ICT devices and services: devices or services for processing information and/or supporting communication, which

impairment: reduction or loss of psychological, physiological or anatomical function or structure of a user

keyword: word that the speech recognition system is looking for in word spotting mode

NOTE: A menu dialogue offers a user a series of lists of choices from which a series of selections can be made.

phonetic discriminability: ability to discriminate between words based on the analysis of their constituent phones

spoken command: verbal or other auditory dialogue format which enables the user to input commands to control a

supplementary service: additional service that modifies or supplements a basic telecommunication service

NOTE: Consequently, it cannot be offered to a customer as a stand-alone service; it has to be offered in

association with a basic telecommunication service. The same supplementary service may be common to

a number of basic telecommunication services. See ITU-T Recommendation I.210 [3].

usability: effectiveness, efficiency and satisfaction with which specified users achieve specified goals in particular

user interface: elements of a product used to control it and receive information about its status, and the interaction that

user requirements: requirements made by users, based on their needs and capabilities, in order to make use of a

word spotting mode: special state of the recognition system in which no speech is recognized or processed other than a

NOTE: A typical usage is in a dormant state of the speech recognizer, where issuing a "wake up" command (also

Intended users of the present document are those designing, developing, implementing and deploying ICT devices and

Intended end users mentioned in the present document are people who use ICT devices and services with a speech

Uniformity in the interactive elements increases the transfer of learning between different devices and services. Such

knowledge transfer becomes even more important in a world of ubiquitous devices and services using speech

recognition technology. In particular standardized commands improve the overall usability of the entire interactive

environment. Use of the generic vocabulary of spoken commands in the present document for the development of ICT

A generic spoken command vocabulary will particularly benefit some end users with temporary or permanent additional

needs, such as those with literacy difficulties, people with visual or cognitive impairments, those with an impaired

For further guidance, including specifics of user impairments and resulting disabilities, assistive technologies, design

Ideally, a spoken command vocabulary should be intuitive, easy to learn, memorable, natural, and unambiguous. A

• the ability to handle the vagaries of speech recognizers in a reliable and predictable way, maximizing the user

Adequate feedback should be provided to users indicating, where applicable, that a command cannot be executed when

In order to meet the requirements stated in clause 4, where the standard is designed for a wide range of end users, an

empirical method has been employed for the elicitation and validation of potential voice commands. Native speakers of

the 30 languages were sampled for this data collection. The previous standard used an online method of data collection

where respondents were asked to complete a questionnaire. This worked well for the five most frequently spoken

languages of the EU. However, the extension of the standard covers countries where internet penetration is relatively

low and online questionnaires for these countries would not yield a representative sample of users for the purposes of

In addition to elicitation and validation, a procedure of phonetic discriminability has been applied to the candidate

commands to ensure minimal confusion with commands that are likely to be simultaneously available.

These phases are outlined here. More detailed descriptions of each phase can be found in annex A.

In this phase, a sample of native speakers representing three age groups, aiming for an equal distribution of men and

women, were invited to take part in an interview on voice commands. At this stage, they were given some general

background to the aims of the study in order to inform them of the aims of the study prior to gaining their consent to

participating in the research. In most cases the interview was conducted by telephone but, in a small number of cases, an

interview was conducted with interviewer and interviewee sitting back to back in order to prevent artefacts based on the

interviewer's reactions. The interviewer, or Native Language Assistant (NLA), was also always a native or near-native

speaker who also carried out translations and transcriptions from documents in the original English and conducted

analyses. They read out, for each command, a phrase describing the function of the device or service, known as the

Carefully Worded Description (CWD), without mentioning any of the most likely resulting terms. The interviewees

were then asked to name the term or terms they would find most suitable as a command in the context of a spoken-

EXAMPLE: The carefully worded description used for describing the supplementary service "Call deflection"

was: "You hear the phone ring at a time when you do not want to speak to anyone. You want the

connection to be passed on to another name or number instead. What command would you give

From this process a number of different alternative command candidates were collected. The lists of terms were then

processed in order to reduce the number of morphological forms, e.g. infinitive or imperative, singular or plural, formal

or informal addressing. The data were also checked for typological errors and answers which did not reflect the function

implied by the carefully worded descriptions. The resulting terms were ordered according to the percentage of

participants who had named them, and the most frequently chosen terms were used as input to the validation phase.

In identifying the appropriate spoken commands it is not sufficient to conduct elicitation alone. It was also necessary to

rank the proposed terms in order to provide a degree of validation. Therefore, validation interviews were set up and

carried out in a similar way to elicitation interviews where the candidate commands were ranked in order of preference

by the participants (see clause A.2). The top-ranked commands were then put forward to the phonetic discriminability

The method described here was applied to the majority of the languages. However, it became clear that this method

was an unnecessary use of resources as the same result could be obtained by subjecting the results from discrimination

to expert analysis. Therefore, (see clause A.2), expert analysis was applied to those languages which had not undergone

validation, namely: Estonian, Greek, Icelandic, Latvian, Maltese, Norwegian, Portuguese, Raeto-Romance, Swedish,

and Turkish to identify the spoken commands which were chosen for phase 3, phonetic discriminability. The experts

comprised a combination of: the NLAs, industry experts, linguistic and cultural representatives from the countries

Whilst the previous two steps have provided a user-centric approach to the selection of command words, it is still

EXAMPLE: A selection of words may be chosen as a result of the previous two phases that have a high level of

However, if this selection gives rise to a high degree of confusability in the speech recognizer, between words which are

available for use in the same context, then the overall goal of usability is nullified. Therefore, discriminability analysis

was carried out to ensure that command words that are likely to be active simultaneously in a dialogue context can be

a) Commands were clustered according to those which would be simultaneously available, e.g. all commands for

b) For each context, the top three commands from validation were assessed by native-language experts with

respect to their sounds and not to their orthographic forms. Commands were listed as potentially phonetically

d) An alternative for one of the command words was chosen, with minimum repercussion with respect to the

The final pass on the resulting command set was performed by submitting the results to a number of different groups for

• Educated native speakers to ensure consistency within the entire language set in terms of morphological and

• Cultural and linguistic institutes of each of the languages represented in the standard.

• The industry reference group. This is a body of experts from industry, such as service