prEN IEC 62625-3:2026

SLOVENSKI STANDARD
01-marec-2026
Železniške elektronske naprave - Sistem registriranja podatkov o vožnji vlaka - 3.
del: Avdio in video snemanje
Electronic railway equipment - On board driving data recording system - Part 3: Audio
and video recording
Matériel électronique ferroviaire - Système embarqué d'enregistrement de données de
conduite - Partie 3: Enregistrement audio et vidéo
Ta slovenski standard je istoveten z: prEN IEC 62625-3:2026
ICS:
03.220.30 Železniški transport Transport by rail
33.160.01 Avdio, video in avdiovizualni Audio, video and audiovisual
sistemi na splošno systems in general
45.020 Železniška tehnika na Railway engineering in
splošno general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

9/3297/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 62625-3 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2026-01-02 2026-03-27
SUPERSEDES DOCUMENTS:
9/3158/CD, 9/3176A/CC
IEC TC 9 : ELECTRICAL EQUIPMENT AND SYSTEMS FOR RAILWAYS
SECRETARIAT: SECRETARY:
France Mr Denis MIGLIANICO
OF INTEREST TO THE FOLLOWING COMMITTEES: HORIZONTAL FUNCTION(S):

ASPECTS CONCERNED:
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TITLE:
Electronic railway equipment - On board driving data recording system - Part 3: Audio and video recording

PROPOSED STABILITY DATE: 2028
NOTE FROM TC/SC OFFICERS:
electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.
You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without
permission in writing from IEC.

IEC CDV 62625-3 © IEC 2026
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions, abbreviated terms . 9
3.1 Terms and definitions . 9
3.1.1 accident . 9
3.1.2 incident . 9
3.1.3 active driver’s cab . 9
3.1.4 driver’s cab . 9
3.1.5 crew . 9
3.1.6 driver’s cab crew . 9
3.1.7 soundscape . 9
3.1.8 V-T capability . 9
3.1.9 V-C capability . 10
3.1.10 train data . 10
3.1.11 A-C capability . 10
3.1.12 A-A capability . 10
3.1.13 storage medium . 10
3.1.14 persistent . 10
3.1.15 non-persistent. 10
3.1.16 sequence . 10
3.1.17 capture . 10
3.1.18 recording . 10
3.1.19 retrieval . 10
3.1.20 audio capture . 11
3.1.21 audio sample . 11
3.1.22 audio flow . 11
3.1.23 audio recording . 11
3.1.24 audio sequence . 11
3.1.25 audio retrieval . 11
3.1.26 audio track . 11
3.1.27 scene . 11
3.1.28 image capture . 11
3.1.29 digital image . 11
3.1.30 video flow . 11
3.1.31 video capture . 12
3.1.32 video footage . 12
3.1.33 video sequence . 12
3.1.34 video recording . 12
3.1.35 video retrieval . 12
3.1.36 storage . 12
3.1.37 storage duration . 12
3.1.38 conservation . 12
3.1.39 conservation duration . 12
3.1.40 intercom function . 12
3.1.41 intercom system . 12
IEC CDV 62625-3 © IEC 2026
3.2 Abbreviated terms . 12
4 Requirements . 14
4.1 Definition of the capabilities and related functions . 14
4.1.1 General . 14
4.1.2 Context diagram . 15
4.1.3 Data models . 15
4.1.4 Functional chain . 16
4.2 Applicability of clauses . 17
4.3 Conventions . 17
4.4 Operating modes . 17
4.4.1 Application . 17
4.4.2 General timing performance . 17
4.4.3 Main operating modes . 18
4.4.4 Substates of the operating mode . 19
4.5 Driver’s cab integration aspects . 20
4.6 Data context for time stamping and device capture identification. 21
4.6.1 Application . 21
4.6.2 Requirements . 21
4.7 Maximum delays in the functional chain . 21
4.7.1 Application . 21
4.7.2 Requirements . 21
4.8 Video and audio capture . 21
4.8.1 Video capture of the track from the driver’s cab (V-T) . 21
4.8.2 Capture the scenes in the driver’s cab (V-C) . 23
4.8.3 Capture of the soundscape in the driver’s cab (A-A) . 24
4.8.4 Capture of the conversations from driver’s cab communication devices
(A-C) . 24
4.9 Video and audio recording . 26
4.9.1 Purpose . 26
4.9.2 Requirements . 26
4.10 Audio video retrieval . 29
4.10.1 Purpose . 29
4.10.2 Requirements . 29
4.11 General performance of the on-board functional chain . 30
4.11.1 Purpose . 30
4.11.2 Requirements . 30
5 Non-functional requirements . 33
5.1 Reliability/availability/maintainability . 33
5.2 Cybersecurity . 33
5.2.1 General . 33
5.2.2 Class CYBER0 . 34
5.2.3 Class CYBER1 . 34
6 Conformity statement. 34
Annex A (informative) Rational, guidance and examples of audio and video capture
performances . 35
A.1 Purpose of this annex . 35
A.2 V-T capability – capture resolution . 35
A.2.1 Introduction . 35
A.2.2 Determination of the capture resolution from the visual acuity . 36
IEC CDV 62625-3 © IEC 2026
A.2.3 Example of application using forward visibility angles . 38
A.3 V-T Capability – capture sampling frequency . 41
A.3.1 Introduction . 41
A.3.2 Capture fixed object. . 41
A.3.3 Capture object states changes. . 43
A.3.4 Capture an Object Moving in the Opposite Direction. . 44
A.3.5 Capture an object moving in the lateral direction. . 45
A.3.6 Synthesis . 47
A.4 A-A capability – audio capture performances . 48
A.4.1 Introduction . 48
A.4.2 Human hearing acuity . 48
A.4.3 Audio capability of a driver . 51
A.4.4 Soundscape in a driver’s cab . 51
A.4.5 Performances for audio capture . 51
Bibliography . 53

Figure 1 - Context diagram of ODDRS for this document . 15
Figure 2 – Data model for video content applicable to V-T and V-C capabilities . 16
Figure 3 – Data model for audio content applicable to A-C and A-A capabilities . 16
Figure 4 - Functional overview . 17
Figure 5 - Main operating modes . 19
Figure 6 – Sub-modes of the operating mode . 19
Figure 7 – Functional interaction diagram between audio capture and intercom
functions . 25
Figure 8 – Minimum storage duration . 27
Figure 9 – Maximum time lag between retrieved digital images . 31
Figure 10 – Maximum lag between retrieved data - digital image and audio samples . 32
Figure 11 – Maximum lag between retrieved audio samples . 32
Figure A.1 – Visual acuity measurement . 36
Figure A.2 – Converting visual acuity to spatial period. . 36
Figure A.3 – Eccentricity factor . 37
Figure A.4 – Contrast factor . 37
Figure A.5 – Age factor . 38
Figure A.6 – Vertical field of view according to EN 16186-1:2014, Annex A. 39
Figure A.7 – Horizontal field of view according to EN 16186-1:2014, Annex A . 39
Figure A.8 – Vertical field of view according to EN 16186-1:2014, Annex C . 40
Figure A.9 – Horizontal field of view according to EN 16186-1:2014, Annex C . 40
Figure A.10 – Fixed object capture . 42
Figure A.11 – Overhead railway sign capture . 43
Figure A.12 – Capture of an object moving in the opposite direction. . 44
Figure A.13 – Capture an object moving in the lateral direction. . 46
Figure A.14 – Field of view of the driver’s cab . 46
Figure A.15 – Audible frequencies spectrum 1 . 48
Figure A.16 – Audible frequencies spectrum 2 . 49
Figure A.17 – Audible frequencies spectrum . 50
Figure A.18 – Human auditory characterisation . 50
IEC CDV 62625-3 © IEC 2026
Table 1 – Terminology used in the data models . 15
Table 2 – Parameters associated with operating modes . 18
Table 3 – Parameters associated with data storage duration performances . 28
Table 4 – Non-functional requirements . 33
Table 5 – Non-functional requirements – CYBER0 class . 34
Table A.1 – Minimum capture sampling frequency for fixed objects . 42
Table A.2 – Examples of rail vehicles. 43
Table A.3 – Minimum capture sampling frequency for an object moving in the opposite
direction. . 45
Table A.4 – Speed range of object moving in the lateral direction . 46
Table A.5 – Minimum capture sampling frequency . 47
Table A.6 – Driver’s cab noise example . 51

IEC CDV 62625-3 © IEC 2026
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRONIC RAILWAY EQUIPMENT –
ON BOARD DRIVING DATA RECORDING SYSTEM –

Part 3: Audio and video recording

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardisation comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62625-3 has been prepared by IEC technical committee 9: Electrical
equipment and systems for railways.
The text of this International Standard is based on the following documents:
FDIS Report on voting
XX/XX/FDIS XX/XX/RVD
Full information on the voting for the approval of this International Standard can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
IEC CDV 62625-3 © IEC 2026
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
The National Committees are requested to note that for this document the stability date
is 20XX.
THIS TEXT IS INCLUDED FOR THE INFORMATION OF THE NATIONAL COMMITTEES AND WILL BE DELETED
AT THE PUBLICATION STAGE.
IEC CDV 62625-3 © IEC 2026
1 INTRODUCTION
2 The international standard IEC 62625-1 and IEC 62625-2 set common requirements of an On-
3 board Driving Data Recording System (ODDRS) and the conformity testing that can be referred
4 to by the regulations. The purpose of the ODDRS is to record data about the operation of the
5 train. Driving analyses can be carried out to support systematic analysis of incidents and
6 accidents and audit of the driver’s ability and qualification to operate the train.
7 IEC 62625-1 and IEC 62625-2 cover the recording of data which mainly consist of signalling
8 events, driver actions and train behaviour. These data support the accident or incident
9 investigation when driver’s actions or technical failure of an on-board system could have
10 contributed to the cause. In some cases, though it may be beneficial to the investigation to have
11 an audio and video recording of the situation from driver’s perspective as driver mainly uses his
12 sight and hearing senses as a basis for his decisions, and a main cause leading to an accident
13 may have been located outside the vehicle (e.g. an obstacle in the path of the train).
14 This document complements the IEC 62625-1 by adding requirements on audio and video
15 recording in the context of train operation examinations during accident investigations or driving
16 audits on:
17 – what the driver has said;
18 – what the driver should have heard
19 – what the driver should have seen;
20 – what actions the driver was performing at its driver desk.
21 NOTE The modal verb “should” is used to describe normative behaviour of the driver without absolute certainty as
22 the human sensory processing is not deterministic.
23 This document takes into consideration that (i) some national or regional regulations, labour
24 agreements, etc., may restrict the sound and visual fields allowed for recording, (ii) all sound
25 and visual fields are not required to be recorded.
26 Requirements and features of the ODDRS specified in this document may alternatively be
27 implemented by other on-board systems, e.g. CCTV, PIS.
IEC CDV 62625-3 © IEC 2026
29 ELECTRONIC RAILWAY EQUIPMENT –
30 ON BOARD DRIVING DATA RECORDING SYSTEM –
32 Part 3: Audio and video recording
34 1 Scope
35 This document specifies additional requirements to IEC 62625-1 of an On-Board Driving Data
36 Recording System (ODDRS) for the purpose of recording audio and video in the context of
37 supporting systematic analysis of incidents, accidents or driving audits. It defines the
38 requirements to capture, to store and to retrieve of audio and visual scenes from within the
39 driver’s cab and from the front-facing view.
40 This document is applicable to audio and video recording of:
41 – driver’s conversations performed via wired fixed train intercom communication devices;
42 – view of the track from the driver’s cab;
43 – ambient sound and voices spoken in the driver’s cab;
44 – view of the driver’s desk;
45 – view of the driver’s cab.
46 This document does not apply to audio and video recording of:
47 – passenger areas in the train;
48 – passenger entrance to the train;
49 – on-board technical devices such as pantographs, bogies, doors, etc;
50 – other areas for authorized crew members such as conductor compartment, galley, etc.
51 This document defines the audio and video recording capabilities of the ODDRS with a certain
52 flexibility level. The value of this capability is defined by the categories of sound and visual
53 fields captured and recorded. This standard does not specify the selection of audio and video
54 sources to perform the above functions.
55 2 Normative references
56 The following documents are referred to in the text in such a way that some or all of their content
57 constitutes requirements of this document. For dated references, only the edition cited applies.
58 For undated references, the latest edition of the referenced document (including any
59 amendments) applies.
60 IEC 62625-1 Electronic railway equipment - On board driving data recording system –
61 Part 1: System specification
62 IEC 62443 series Security for industrial automation and control systems
IEC CDV 62625-3 © IEC 2026
63 3 Terms, definitions, abbreviated terms
64 3.1 Terms and definitions
65 For the purposes of this document, the following terms and definitions apply.
66 ISO and IEC maintain terminology databases for standardisation use at the following addresses:
67 – ISO Online browsing platform: available at https://www.iso.org/obp
68 – IEC Electropedia: available at https://www.electropedia.org
69 3.1.1
70 accident
71 an unintended event or series of events that results in death, injury, loss of a system or service,
72 or environmental damage
73 [SOURCE: IEC 62625-1:2013, 3.1.1]
74 3.1.2
75 incident
76 any occurrence, other than accident or serious accident, associated with the operation of trains
77 and which may affect the safety of operation
78 [SOURCE: IEC 62625-1:2013, 3.1.3]
79 3.1.3
80 active driver’s cab
81 driver's cab that is currently in operation and controlling the train's movement
82 Note 1 to entry: This means it's the driver’s cab where the driver is actively driving the train and interacting with the
83 controls
84 3.1.4
85 driver’s cab
86 part of a vehicle used for driving the vehicle or train, forming a separate compartment
87 [SOURCE: IEC 60050-811:2017, 811-02-44]
88 3.1.5
89 crew
90 authorised members aboard the train during the train service operation
91 Note 1 to entry: For authorized crew members presents during train service operation in the driver’s cab, the term
92 driver’s cab crew is used
93 3.1.6
94 driver’s cab crew
95 authorised crew members present during train service operation in the driver’s cab
96 3.1.7
97 soundscape
98 area of interest audibly covered by audio capture function
99 3.1.8
100 V-T capability
101 ability to provide the images and video sequences of the track from the driver's cab for later analysis
IEC CDV 62625-3 © IEC 2026
102 3.1.9
103 V-C capability
104 ability to provide the images and video sequences of the driver’s cab for later analysis
105 3.1.10
106 train data
107 data relevant to train operation according to IEC 62625-1:2013, 1
108 3.1.11 A-C capability
109 ability to provide audio sequences of driver conversations and announcements for subsequent
110 analysis
111 3.1.12
112 A-A capability
113 ability to provide audio sequences from the soundscape of the driver's cab for later analysis
114 3.1.13
115 storage medium
116 device or set of devices providing the means to store video footage or audio tracks
117 3.1.14
118 persistent
119 ability to retain information without the need for (electrical) energy
120 3.1.15
121 non-persistent
122 antonym of persistent term
123 Note 1 to entry: which exists for a limited time and disappears, for example, when electrical energy is lost
124 3.1.16
125 sequence
126 audio or video sequence
127 3.1.17
128 capture
129 process consisting of acquiring data
130 Note 1 to entry: In the context of this document, the data is identified as soundscape (audio context) or landscape
131 (video context)
132 3.1.18
133 recording
134 process consisting of transforming non-persistent captured data into persistent data on a storage
135 medium
136 3.1.19
137 retrieval
138 process retrieving and delivering previously stored recording information on a storage medium
139 Note 1 to entry: Data retrieval is performed by duplication of the data stored on the storage medium or by a direct
140 extraction of the storage medium itself
IEC CDV 62625-3 © IEC 2026
141 3.1.20
142 audio capture
143 capturing continuously sound samples from the soundscape
144 3.1.21
145 audio sample
146 short segment of captured sound
147 3.1.22
148 audio flow
149 audio samples of the soundscape captured continuously
150 Note 1 to entry: The audio flow can be compared with the video flow in terms of abstraction
151 3.1.23
152 audio recording
153 audio flow (non-persistent information) into audio tracks conversion (persistent information)
154 3.1.24
155 audio sequence
156  segment of an audio track framed by two time stamps
157 Note 1 to entry: The audio sequence is similar to the video sequence in terms of abstraction level
158 3.1.25
159 audio retrieval
160 providing audio tracks stored on a storage medium
161 Note 1 to entry: Data retrieval from the storage medium is performed by data duplication or a direct extraction
162 3.1.26
163 audio track
164 audio video on board driving data recording system specific audio flow recorded in a persistent way on
165 a storage medium without considering a specific period delimited by 2 absolute date/time bounds
166 [SOURCE: IEC 60050-806:1996, 806-17-14, modified, domain has been added]
167 Note 1 to entry: The audio track is compared with the video footage in terms of abstraction level
168 3.1.27
169 scene
170 area of interest visually covered by the capture function
171 3.1.28
172 image capture
173 snapshot of a scene in the form of a digital image
174 3.1.29
175 digital image
176 image consisting of pixels using ranges of discrete values
177 [SOURCE: IEC 62676-1-1:2013,3.1.44]
178 3.1.30
179 video flow
180 succession of digital images
IEC CDV 62625-3 © IEC 2026
181 Note 1 to entry: the way to implement the succession of digital images into a video flow is not addressed by this
182 document.
183 3.1.31
184 video capture
185 consisting of continuously capturing images of a scene to provide a video flow
186 3.1.32
187 video footage
188 specific video flow that is being recorded in a persistent way on a storage medium
189 3.1.33
190 video sequence
191 segment of recorded data on a storage medium framed by two time-stamps
192 3.1.34
193 video recording
194 transformation of a video flow (non-persistent information) into video footage (persistent
195 information)
196 3.1.35
197 video retrieval
198 consisting of providing video sequence from video footage
199 3.1.36
200 storage
201 operation or a device ensuring that recorded data is persistently preserved and available for retrieval
202 3.1.37
203 storage duration
204 time during which recorded data is stored in the ODDRS before it can be deleted (overwritten)
205 3.1.38
206 conservation
207 action of preventing recorded data from being lost, altered or destroyed outside the operational use of
208 the storage medium, typically during a long storage period without power
209 3.1.39
210 conservation duration
211 duration covering the conservation time needed for recorded data
212 3.1.40
213 intercom function
214 function in the train in charge of the audio communications (i) between on-board crew members and
215 (ii) between on-board crew members and passengers
216 3.1.41
217 intercom system
218 system implementing the intercom function
219 Note 1 to entry: In the scope of this document, the intercom system only considers the hard-wired train borne
220 communication system
221 3.2 Abbreviated terms
CCTV: Closed-Circuit TeleVision
ETCS: European Train Control System
HL: Hearing Loss
IEC CDV 62625-3 © IEC 2026
HMI: Human Machine Interface
INTERCOM: Inter Communication system
MTBF: Mean Time Between Failures
ODDR: On Board Driving Data Recording
ODDRS: On Board Driving Data Recording System
PIS: Passenger Information System
SNR: Signal to Noise Ratio
USB: Universal Serial Bus
UTC: Universal Time, Coordinated
DMU: Diesel Multiple Unit
EMU: Electrical Multiple Unit
V-T: Video – Track, abbreviated term for V-T capability
V-C: Video – Cab, abbreviated term for V-C capability
A-C: Audio – Communication, abbreviated term for A-C capability
A-A: Audio – Ambient, abbreviated term for A-A capability
IEC CDV 62625-3 © IEC 2026
224 4 Requirements
225 4.1 Definition of the capabilities and related functions
226 4.1.1 General
227 This document of the IEC 62625 series defines four video and audio capabilities which
228 complement the capabilities of the on-board driving data recording system ODDRS specified in
229 IEC 62625-1 to support systematic analysis of incidents, accidents, and driving audits more
230 effectively (see Figure 1):
231 – V-T capability;
232 NOTE 1 To capture the view of the track from the driver’s cab by providing video footage and images
233 – V-C capability;
234 NOTE 2 To capture the view of the driver’s cab by providing video footage and images
235 – A-A capability;
236 NOTE 3 To capture the soundscape in the driver’s cab by providing audio tracks
237 – A-C capability.
238 NOTE 4 To capture Conversations and announcements from the driver’s cab communication functions by providing
239 audio tracks
240 The ODDRS may cover one or more video and audio capabilities.
241 Where the ODDRS implements video and audio capabilities, the requirements associated with
242 the video and audio capabilities shall be applicable.
243 NOTE 5 The determination of video and audio capabilities should depend, for example, on the recommendations of
244 the investigative body, national safety authority guidelines, national regulations, and train operating rules.
245 Consequently, the implementation should vary from country to country. For example, a country can implement only
246 V-T capability, a second country V-T and A-A capabilities, and a third country all video and audio capabilities V-T,
247 V-C, A-C and A-A.
IEC CDV 62625-3 © IEC 2026
248 4.1.2 Context diagram
249 Figure 1 summarises the main interactions between the functions of the V-T, V-C, A-A, A-C,
250 capabilities and the other stakeholders (boxes for the systems or main actors presented in the
251 diagram). These stakeholders could be other on-board / wayside systems, or people that use
252 the data provided by the ODDRS supporting the functions described in this document.
256 NOTE Each interaction, symbolised by an arrow line, is completed by the list of main information involved in the
257 interactions. The diagram recalls more specifically the interaction with the ODDRS (IEC 62625-1) supporting the
258 functions required by the IEC 62625-1 (presented as a circle with a dotted line in the diagram).
259 Figure 1 - Context diagram of ODDRS for this document
260 4.1.3 Data models
261 The data model presented in Figure 2 for the video and in Figure 3 for the audio helps to
262 understand the relationships between all the data entities presented in this document, from the
263 Train Environment Entity to the final sequence entities. Figure 2 and Figure 3 presents the
264 associations between the entities,(the association terminology is described in Table 1), their
265 nature and their cardinalities with the support of the short description details the way of a “input
266 entity” is linked to the “output entity”.
267 Table 1 – Terminology used in the data models
Association type Description
one entity can associate with (n) multiple entities, but not vice versa. The
named association 1.n
nature of the association can be indicated on the links.
“is composed of” association one entity consists of one or more other entities.
“is captured by” association one entity can be captured by one or more entities
“is recorded into” association one entity can be recorded into one or more entities
“is stored on” one entity can be stored in one or more other entities
“contents” association one entity can contain one or more other entities
IEC CDV 62625-3 © IEC 2026
271 Figure 2 – Data model for video content applicable to V-T and V-C capabilities
273 Figure 3 – Data model for audio content applicable to A-C and A-A capabilities
274 4.1.4 Functional chain
275 As presented in Figure 4, requirements for video and audio capabilities are defined according
276 to the functional division into three basic functions:
277 – Capture function which samples the scenes into digital video flows and, the soundscapes
278 into audio flows (refer to 4.8);
279 – Recording function which transforms the video flows into video footage and, the audio flows
280 into audio tracks (refer to 4.9);
281 – Retrieval function which delivers the video footage and the audio tracks stored in the
282 ODDRS to submit them to the analysis function (refer to 4.10).
283 An analysis function  supported by the offline analysis system which enables an investigator
284 or an auditor to analyse the recorded train data (audio tracks and video footage) is considered
285 outside the scope of ODDRS.
IEC CDV 62625-3 © IEC 2026
287 Figure 4 - Functional overview
288 4.2 Applicability of clauses
289 Where a law, regulation or other legislative text in force limits or opposes the application of a
290 clause, the clause is inapplicable or applicable within the limits authorised by the regulatory
291 constraints.
292 4.3 Conventions
293 By convention, where no indication is provided,
294 – the clauses are applicable to Recording, Retrieval functions of V-T, V-C, A-A and A-C
295 capabilities;
296 – the clauses are applicable to Capture function of V-T, V-C and A-A capabilities only
297 considering that the A-C capture is delegated to the intercom system and has limited
298 dependencies with this document
299 When the application of clauses is selective, a specific clause (Application) indicates the
300 capabilities and the functions covered by the clauses.
301 4.4 Operating modes
302 4.4.1
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