Technical Bulletin

eCall Additional Data Concept
Triggering Incident
Version 1.0.0
June 2022
TB 040TitleeCall Additional Data Concept Triggering Incident

Version

1.0.0

Document Number

TB 040

AuthorF. MaasDate

June 2022

Related Documents

Rescue Protocol

StatusFinal

Application Date

2024

Copyright ©Euro NCAP 2022 - This work is the intellectual property of Euro NCAP.
Permission is granted for this material to be shared for non-commercial, educational
purposes, provided that this copyright statement appears on the reproduced materials andnotice is given that the copying is by permission of Euro NCAP. To disseminate otherwise
or to republish requires written permission from Euro NCAP.

Preface

Stakeholders have been working for some years on the concept of a pan-European in-vehicle
emergency call ('eCall') which has the potential of saving over 2000 lives annually in the EU
on top of the reduction in injury severity. Installation of eCall is mandatory for each new typeof passenger car which is approved after March 2018. It is, in short, a system to inform 112centers (commonly known as PSAPs or public safety answering points) about thewhereabouts of an incident. With the call, made over a mobile network, a set of data istransferred which is defined in CEN standard EN 15722. This set of data (known as MSD)
can be used in the emergency process, on top of any information retrieved from the occupantsof the car.
The forenamed CEN standard makes a provision for additional data that can be embedded in
the MSD. This additional data is called ‘optional additional data’ and should be well definedalong the guidelines laid out in EN 15722. It shall, amongst other things, have an ASN.1
encoding scheme, be limited in space and provide well defined meaning of the information
elements.
The MSD itself contains relevant but limited information and has no provision for
information about the triggering incident. Other than the fact that if an eCall is automaticallytriggered (as opposed to user-initiated) the incident must have been severe enough. Based on
its experience Euro NCAP has defined an additional data concept for eCall that gives
information about the triggering incident. This information can help the emergency services
to better and more efficiently respond to an incident.

DISCLAIMER: Euro NCAP has taken all reasonable care to ensure that the information
published in this document is accurate and reflects the technical decisions taken by theorganisation. In the unlikely event that this protocol contains a typographical error or any
other inaccuracy, Euro NCAP reserves the right to make corrections and determine theassessment and subsequent result of the affected requirement(s).

EUROPEAN NEW CAR ASSESSMENT PROGRAMME (Euro NCAP)

Table of Contents

1.
2.
3.
4.
5.
6.

Scope........................................................................................................................................... 6
Normative references .................................................................................................................. 6
Terms and Definitions................................................................................................................. 7
Symbols and abbreviations ......................................................................................................... 7
Conformance ............................................................................................................................... 8
Requirements .............................................................................................................................. 8
6.1
General ................................................................................................................................ 8
6.2
Concepts and formats .......................................................................................................... 8
6.2.1
MSD data concepts ..................................................................................................... 8
6.2.2
Representation of MSD data concepts ........................................................................ 8
6.2.3
The Euro NCAP additional data concept for incident information ............................. 8
6.2.3.1 The ‘Object Data’ ....................................................................................................... 8
6.2.3.2 The ‘Object Identifier’ ................................................................................................ 9
6.3
Contents of the ‘Minimum Set of Data’ (MSD) ................................................................. 9
6.3.1
Basic contents of MSD ............................................................................................... 9
6.3.2
Contents of the optionalAdditionalData..................................................... 10
6.4
Mode of operation ............................................................................................................. 11
7. Triggering incident information elements................................................................................. 11
7.1
Impact ............................................................................................................................... 11
7.1.1
Location of impact .................................................................................................... 12
7.1.2
Rollover..................................................................................................................... 13
7.2
De- or increase of vehicle speed ....................................................................................... 13
ASN.1 definition of additional data block ........................................................................................ 15
A.1
General .............................................................................................................................. 15
A.2
Definition of contents of optionalAdditionalData............................................................. 15
A.2.1
Context ...................................................................................................................... 15
A.2.2
ASN.1 definition ....................................................................................................... 15
A.2.3
Syntax check of ASN.1 definition ............................................................................ 16
A.2.4
Example .................................................................................................................... 16

TB 040

1.

Scope

In this document Euro NCAP defines an additional data concept that can be transferred as the‘optional additional data’ part of an (automatic) eCall MSD, as defined in EN 15722, that may
be transferred from a vehicle to a PSAP in the event of a crash or emergency via an eCallcommunication session.
The purpose of this document is to provide means to notify the PSAP about some details of thetriggering incident, in order for the PSAP or another emergency service to be able to better
estimate the severity of the incident. This can be beneficial to the efficiency of the emergency
response.
This document can be seen as an addendum to CEN standard EN 15722; it contains as little
redundancy as possible.
NOTE 1This document is not a CEN standard, but for readability and better implementation it follows the
structure of such document.

NOTE 2

The additional data concept defined herein will be submitted to a relevant data registry if suchregistry exists.

2.

Normative references

The following documents are referred to in the text in such a way that some or all of theircontent constitutes requirements 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.
Organisation Document Reference

Title

CEN

EN15722

eCall minimum set of data (ITS/eSafety)

ISO/IECISO 8825-2

ASN.1 encoding rules/specification of PER

ISO/IECISO 4130

Road vehicles — Three-dimensional reference systemand fiducial marks — Definitions

ISO/IEC

ISO 12353

Road vehicles — Traffic accident analysis — Part 1:
Vocabulary6

TB 040

3.

Terms and Definitions

Where applicable definitions are copied from existing sources (which are then referenced)
Term

Definition

coordinate system

set of reference lines used to identify the location of points in a certain
space

delta-vdifference between velocity just at (t0) and just after (t1) the beginningof the triggering incident where the difference between t0 and t1 is equal
to 250ms (∆𝑣 = 𝑣𝑡1 − 𝑣𝑡0 )Note 1 to entry: also see ISO 12353

eCall

emergency call generated either automatically via activation of invehicle sensors or manually by the vehicle occupants; when activated it
provides notification and relevant location information to the mostappropriate 'Public Safety Answering Point’, by means of mobile wirelesscommunications networks, carries a defined standardised ‘Minimum Set
of Data’ notifying that there has been an incident that requires response
from the emergency services, and establishes an audio channel between
the occupants of the vehicle and the most appropriate 'Public Safety
Answering Point' (ref: CEN EN15722 et al)vehicle coordinate right-handed coordinate system with a selected origin for defining thelocation of points on the vehicle
systemNote 1 to entry: See ISO 4130.

4.

Symbols and abbreviations

For the purposes of this document, the following symbols and abbreviations apply.
ASN.1 abstract syntax notation one
Δvdelta vM

mandatory

MSD

minimum set of dataO

optional

OID

object identifier

PSAPpublic safety answering point

UPER

unaligned packed encoding rules (ASN.1)

7

TB 0405.

ConformanceThis additional data standard does not change the common conformance requirements that haveto be met by eCall devices. Correctness and reliability of the data included in the MSD basedon this document shall be proven by written documentation.

6.

Requirements

6.1

GeneralThis document describes an extension to the CEN standard EN 15722 for the coding of the
MSD message. In addition to the requirements set out in this document, all requirements fromEN 15722 shall be met equally (in respect of this additional data concept).

6.2

Concepts and formats

6.2.1 MSD data concepts
The MSD as defined in CEN standard EN 15722 has an optional additional data block that may
be used to add information elements containing information that might be of relevance in an
emergency rescue situation. Privacy regulations apply and shall be in accordance with theprovisions of EU 2016/679 ‘General Data Protection Requirements’.
6.2.2 Representation of MSD data concepts
The MSD is represented in ‘Abstract Syntax Notation’ (ASN.1) using the ‘Unaligned Packed
Encoding Rules’ (UPER) as defined in ISO/IEC 8825 2. CEN standard EN15722 provides thegeneral ASN.1 encoding scheme and sending sequence. The additional data concept in thisdocument is defined following the provisions made in those documents.
6.2.3 The Euro NCAP additional data concept for incident information
The MSD contains two data elements for additional data: the ‘object identifier’ and the ‘object
data’. Inclusion of any additional data shall be such that the maximum length of the overall(encoded) MSD does not exceed 140 bytes.
6.2.3.1 The ‘Object Data’
Euro NCAP has found that sharing sensor information about the triggering incident with the
PSAP can help to streamline the emergency process further. It may enable the emergency
services to estimate the severity of the triggering incident and assess the condition of theoccupants. Euro NCAP has created a data concept to embed this information in the data element‘object data’ of the MSD in the most economical way possible using an ASN.1 encoding recipe
which can be found in Annex A. It might be that, over time, additional parameters are foundthat can help the emergency rescue process. To accommodate such parameters the concept isdesigned so that an extension most probably can be accommodated using the ASN.1 extension
features. If such extension is not possible an updated version of the concept shall be released8

TB 040
6.2.3.2 The ‘Object Identifier’
The ‘object identifier’ (OID) uniquely identifies the format and meaning of the data, the syntaxof the data structure and the semantic meaning of the additional data concept in the data element‘object data’. For further detail regarding the use of OIDs in eCall, see CEN standard EN
15722.
This additional data-concept for triggering incident information has been registered by EuroNCAP and received OID 1.0.14817.106.2.1.2.8. To accommodate for future, nonbackwards compatible, versions, an arc is added to reference the version of the concept. As thisdocument describes the first version of the data concept, the OID to use is1.0.14817.106.2.1.2.8.1.

Contents of the ‘Minimum Set of Data’ (MSD)

6.3

The following subclauses provide the definition of the minimum set of data that shall be sentfrom the vehicle in case of an automatic emergency call with the Euro NCAP additional data
embedded.
6.3.1 Basic contents of MSD
Table 1 provides a summary of the semantic contents of the MSD, for a full description
please refer to CEN standard EN 15722.
Table 1 — Contents/format of the MSD data concept
M – Mandatory data fieldO – Optional data field

MSD
msdVersion

INTEGER-M

msd
msdStructure…
optionalAdditionalData
oid

RELATIVE-OID

data

OCTET STRINGO

Source: CEN EN 15722
The next clause describes the contents of the optionalAdditionalData block.

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TB 040
6.3.2 Contents of the optionalAdditionalData
Table 2 provides a semantic summary of the semantic contents of theoptionalAdditionalData part of the MSD when filled with this additional data concept
for incident information. The sequence of data presentation shall be as specified in this table
and represented as described in 6.2.2. For clarity the ‘type’ used in Table 2 is a semantic
representation of the type used in the ASN.1 definition. The exact representation is found in
Annex A.
NOTE: Elements do not necessarily start or end on a byte boundary. The real position of the element in thedata-stream is defined by the ASN.1 ‘unaligned packet encoding rules’ (UPER), following the definition
in Annex A.

The MSD data element oid is defined as RELATIVE-OID which means that the first part of
the OID (1.0.14817.106.2.1.2), which is fixed for all eCall additional data concepts,
is not to be transmitted. Hence the value of this data element shall be 8.1.
See clause 7 for a detailed description of the data elements, the values and their meanings.
Table 2 — Contents/format of Euro NCAP additional data
optionalAdditionalData
oid

RELATIVE OID

M Fixed value: 8.1
encoded as OCTET STRING

data
locationOfImpact

ENUM

M The impact location of the triggering incident,
which can be one of these values:
unknown – unknown if a triggering impact
was detectednone– no triggering impact detected
triggering impact detected, …
front– … at front of the carrear– … at rear of the car
driverSide– … at the driver side of the car
nonDriverSide
otherrolloverDetected

BOOLEANO Omitted if vehicle is not equipped/able todetect a rollover, else true or false.
M difference between velocity just after and justbefore impact (delta-v)

deltaV

rangeLimit– … at the other side of the car– … at an unspecified location

INTEGER(100…250)

M Unsigned upper limit of the detection range
for delta-v

10

TB 040deltaVXSIGNED INTEGER(-250…250)
deltaVY

SIGNED INTEGER(-250…250)

6.4

M delta-v measured over the x-axis of thecoordinate system of the vehicle
M delta-v measured over the y-axis of thecoordinate system of the vehicle

Mode of operation

Any IVS can embed the Euro NCAP additional data concept for information about thetriggering incident in the MSD sent. However, the data shall only be embedded in an MSD
which is part of an automatically triggered eCall and provided that the information is (a)available and (b) correct at the time when the eCall was triggered (see also clause 7). This data
concept shall not be embedded in the MSD of a manually triggered eCall.
The receiving (PSAP) system shall extract the data elements from the MSD as specified in
CENstandard
EN
15722.
This
makes
the
data-elementsoidandoptionalAdditionalData available. The value of oid can be used to see whether thedata concept is supported and if so which ASN.1 definition should be used to retrieve the data
elements from optionalAdditionalData.
If the value oid refers to the additional data concept which is the subject of this document,
then the PSAP system can apply the ASN.1 recipe found in Annex A to decode the contents ofoptionalAdditionalData. The decoded values from those contents can then be madeavailable to the operator and/or emergency services. This can lead to a better understanding of
the incident and possibly to a more efficient emergency response.

7.

Triggering incident information elements

CEN standards only define functional requirements about when to trigger an automatic eCall:when an incident is detected which is deemed severe by on-board logic. The decision logic isleft to the manufacturer. Based on their long term experience, Euro NCAP has found that a few
data elements are widely used and their values can be relevant to the emergency services.

7.1

ImpactAlthough not all incidents which are deemed to be severe involve an impact, most incidents doand the fact that there was impact and location of it can play a large role in determining theseverity of the incident. Vehicles may be equipped with sensors that detect an impact andprobably also detect the location of the impact. The data concept defined in this document has
a mandatory element for the (detection and) location of an impact causing or part of thetriggering of the automatic eCall.
The information shared in this data concept is related to the initial incident that triggered theautomatic eCall. Any impact sustained after that triggering incident will not be part of the dataexchanged in the initial MSD nor in case the PSAP requests an updated MSD. This is to avoid
false readings due to malfunctioning of sensors after the initial incident and/or readings about
events that take place after the occupants have left their vehicles.

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TB 040
EXAMPLE: in a classic head-tail collision the vehicle usually first hits the vehicle in front or is first hit by thevehicle behind, which would result in the values front or rear respectively. If the frontal andrear impact are at the same time, the value will be other.

7.1.1 Location of impact
Any vehicle that embeds the data concept for triggering incident information shall provide thedata element locationOfImpact to the emergency services via the MSD, even if thevehicle is not equipped with sensors that can detect (the location of the) impact. The emergency
services can deduce the situation from the value that is embedded:
value of locationOfImpact
unknown

meaning
The vehicle is not equipped with sensors to detect impact or
the sensors were not functioning properly or any otherreason which prevented the on board system to detect
whether or not the vehicle sustained an impact.

none

The reading of the (properly functioning) sensors onboard
does not suggest the vehicle was impacted in the eCall
triggering incident. The automatic triggering of the eCall ishence based on other sensor readings.

front or rear

The reading of the (properly functioning) sensors onboard
show the vehicle sustained impact in the eCall triggering
incident on the front or rear of the vehicle.

driverSide

The reading of the (properly functioning) sensors onboard
show the vehicle sustained impact in the eCall triggering
incident on the side of the vehicle where the driver sits.
In vehicles with singular seating an impact on any side shallbe reported as driverSide.

nonDriverSide

The reading of the (properly functioning) sensors onboard
show the vehicle sustained impact in the eCall triggering
incident on the other side of the vehicle than where thedriver sits.

other

The reading of the (properly functioning) sensors onboard
show the vehicle sustained impact in the eCall triggering
incident on a location other than front/rear/driver side/nondriver side, or on multiple locations.

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7.1.2 Rollover
A special case is the detection of rollover. Not all vehicles are equipped with sensors that candetermine if a rollover has taken place and even if these sensors are available, then a rollover
might take place after the automatic triggering of the incident. However, if and when thevehicle has such sensors and a rollover was detected during/as part of the triggering event, thenthis information may be of interest to the emergency services.
If a vehicle has no sensors or is otherwise unable to detect if a rollover took place, then thedata element shall be omitted from the data embedded in the MSD. If the vehicle has sensors,then the value of the data element shall reflect the detection:
value of rolloverDetected
false

meaning
The reading of the (properly functioning) sensors onboard
does not suggest the vehicle experienced a rollover in thetriggering incident. The automatic triggering of the eCall ishence based on other sensor readings.

true

The reading of the (properly functioning) sensors onboard
show the vehicle experienced any form of rollover in theeCall triggering incident.

7.2

De- or increase of vehicle speed

An important marker used in the detection of an incident is the difference between velocity
just before (t0) and just after (t1) the (start of the) triggering incident. Euro NCAP has defined
the difference between t0 and t1 to be 250ms. This difference in velocity is named delta-v andis measured over both the x- and y-axis of the vehicle coordinate system:
Z
X

Y
X

Figure 1 – Euro NCAP Vehicle Coordinate System

The value for delta-v (𝑣𝑡1 − 𝑣𝑡0 ) is signed a negative delta-vx means that the velocity decreased,assuming the vehicle was driving in the forward direction at the time of the incident.
Under normal circumstances the vehicle is not moving sideways, so the value of delta-vy
usually reveals information about the severity and the direction of the sideway movement at
the time of the incident. As can be seen from the figure a positive value for delta-vy means thatthe vehicle sped up to the right, a negative value relates to speeding up to the left.

13

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In most vehicles the range of detection for delta-v is limited, which means that reporting theupper limit dV should be interpreted as ‘delta-v being dV or above’ and reporting the lower
limit -dV should be interpreted as ‘delta-v being dV or below’. Since there is no set value fordV the data element rangeLimit shall be filled with the vehicle/system specific value.

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ASN.1 definition of additional data block
A.1 General
As soon as the OID has revealed the nature of the data as being ‘Euro NCAP Triggering
Incident Information’ (using the standard eCall MSD message definition, see EN 15722) thedata from the optionalAdditionalData block can be decoded. Either by applying the definitionof the data block to that data (this annex), or by applying a constituted complete eCall MSD
message definition to the MSD received.

A.2 Definition of contents of optionalAdditionalData
A.2.1 Context
This section contains the ASN.1 definition of the extra data.
A.2.2 ASN.1 definition
MSD_ADDITIIONAL_EURONCAP_1
DEFINITIONSAUTOMATIC TAGS ::=BEGIN-- Definition can be used to decode data in the data part-- of optionalAdditionalData in the MSD message.
--- AdditionalData::= SEQUENCE {-oid RELATIVE-OID,-data OCTET STRING (CONTAINING INCINFO)-- }INCINFO ::= SEQUENCE {locationOfImpact
rolloverDetecteddeltaV...
}IILocations,
BOOLEANIIDeltaV,

OPTIONAL,

IIDeltaV ::= SEQUENCE {rangeLimit
INTEGER(100..255),
deltaVXINTEGER(-255..255),
deltaVYINTEGER(-255..255),...
}
IILocations ::= ENUMERATED {unknown(0),none(1),
front(2),rear(3),driverSide(4),nonDriverSide(5),other(6),15

TB 040...
}
END

A.2.3 Syntax check of ASN.1 definition
The syntax is checked (and found correct) with the online OSS Nokalva ASN.1 Playground,found at https://asn1.io/asn1playground/.
A.2.4 Example
The example below is shown in ASN.1 value encoding (plain text):
value1 INCINFO ::= {locationOfImpact front,deltaV {rangeLimit 125,deltaVX -45,
deltaVY 10}}

The same example encoded in UPER (hexadecimal representation, 19 bytes):
08 32 D2 84 80

16