ISO/DTS 12103-3

Road vehicles — Test contaminants for filter evaluation — Part 3: Soot contaminant

Véhicules routiers — Poussière pour l'essai des filtres — Partie 3: Poussière de suie

General Information

• Status: Not Published
• ICS: 43.060.20 - Pressure charging and air/exhaust gas ducting systems
• ICS: 43.060.40 - Fuel systems
• Technical Committee: ISO/TC 22/SC 34 - Propulsion, powertrain and powertrain fluids
• Drafting Committee: ISO/TC 22/SC 34 - Propulsion, powertrain and powertrain fluids
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Completion Date: 03-Oct-2022

RELATIONS

• Revises: ISO/TS 12103-3:2020 - Road vehicles — Test contaminants for filter evaluation — Part 3: Soot contaminant
• Effective Date: 06-Jun-2022

Standards Content (sample)

FINAL
TECHNICAL ISO/DTS
DRAFT
SPECIFICATION 12103-3
ISO/TC 22/SC 34
Road vehicles — Test contaminants for
Secretariat: ANSI
filter evaluation —
Voting begins on:
2022-10-03
Part 3:
Voting terminates on:
Soot contaminant
2022-11-28
Véhicules routiers — Poussière pour l'essai des filtres —
Partie 3: Poussière de suie
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/DTS 12103-3:2022(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2022
---------------------- Page: 1 ----------------------
ISO/DTS 12103-3:2022(E)
FINAL
TECHNICAL ISO/DTS
DRAFT
SPECIFICATION 12103-3
ISO/TC 22/SC 34
Road vehicles — Test contaminants for
Secretariat: ANSI
filter evaluation —
Voting begins on:
Part 3:
Voting terminates on:
Soot contaminant
Véhicules routiers — Poussière pour l'essai des filtres —
Partie 3: Poussière de suie
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on

the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below

or ISO’s member body in the country of the requester.
RECIPIENTS OF THIS DRAFT ARE INVITED TO
ISO copyright office
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
CP 401 • Ch. de Blandonnet 8
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
CH-1214 Vernier, Geneva
DOCUMENTATION.
Phone: [phone]
IN ADDITION TO THEIR EVALUATION AS
Reference number
Email: [e-mail]
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/DTS 12103-3:2022(E)
Website: www.iso.org
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
Published in Switzerland
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
© ISO 2022 – All rights reserved
NATIONAL REGULATIONS. © ISO 2022
---------------------- Page: 2 ----------------------
ISO/DTS 12103-3:2022(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 1

4 Symbols and abbreviated terms..........................................................................................................................................................2

5 Test contaminant ............................................................................................................................................................................................... 3

5.1 Definition ..................................................................................................................................................................................................... 3

5.2 Test contaminant designation .................................................................................................................................................. 3

5.3 Generation of soot aerosol ............................................................................................................................................................ 3

5.4 Particle size distribution ............................................................................................................................................................... 3

5.5 Stability of aerosol concentration and particle size distribution .............................................................. 3

5.6 Chemical composition ...................................................................................................................................................................... 3

6 Analysis equipment and operating procedure .................................................................................................................... 4

6.1 General ........................................................................................................................................................................................................... 4

6.2 Analysis equipment ............................................................................................................................................................................ 4

6.3 Particle size analysis procedure ............................................................................................................................................. 4

6.4 Instrument calibration .................................................................................................................................................................... 4

Annex A (normative) Particle size distributions by number ..................................................................................................... 5

Annex B (informative) Handling and use of contaminant ............................................................................................................ 8

Annex C (informative) Concentration ................................................................................................................................................................. 9

Annex D (informative) Flame operation and morphology ........................................................................................................11

Annex E (normative) Thermal-optical transmission analysis ..............................................................................................13

Annex F (informative) Air-to-fuel ratio .........................................................................................................................................................15

Bibliography .............................................................................................................................................................................................................................16

iii
© ISO 2022 – All rights reserved
---------------------- Page: 3 ----------------------
ISO/DTS 12103-3:2022(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to

the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see

www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 22, Road Vehicles, Subcommittee

SC 34, Propulsion, powertrain and powertrain fluids.
A list of all parts in the ISO 12103 series can be found on the ISO website.

This second edition cancels and replaces the first edition (ISO 12103‑3:2020), which has been technically

revised.
The main changes are as follows:
— modification to requirement regarding analysis equipment;
— modification to requirement regarding instrument calibration.
A list of all parts in the ISO 12103 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www.iso.org/members.html.
© ISO 2022 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/DTS 12103-3:2022(E)
Introduction

This document specifies a grade of test aerosol, which is composed of soot from a combustion source

similar to soot occurring in the environment that motor vehicles are commonly subjected to. This test

contaminant is developed for air filter media and element testing.

Ambient aerosols include at least two distinct modes of aerosol: a sub-micron mode and a super-micron

mode. Generally, the sub‑micron mode comes from combustion sources or condensation of gases. The

super‑micron mode comes from physical abrasion processes and wind‑blown dust. The test dusts

described in ISO 12103-1 can be used to simulate the super-micron mode of ambient aerosol for testing

air filters. The soot aerosol described in this document is intended to simulate the sub‑micron mode of

ambient aerosol.

There are several possible methods of generating soot aerosol, to simulate the sub-micron mode

for air filter testing purposes such as dispersing soot from a powder or using generated soot from a

combustion process.

Particle size of soot dispersed from bulk powder exceeds the environmental soot considerably.

For generated soot from a combustion process, a new procedure is described in this document. Using

aliphatic hydrocarbons, the soot consists of a combination of carbon, organic hydrocarbons and other

substances.
© ISO 2022 – All rights reserved
---------------------- Page: 5 ----------------------
TECHNICAL SPECIFICATION ISO/DTS 12103-3:2022(E)
Road vehicles — Test contaminants for filter evaluation —
Part 3:
Soot contaminant
1 Scope

This document defines particle size distribution by number and chemical content limits involving one

grade of test aerosol made from combustion soot.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

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.

ISO 15900, Determination of particle size distribution — Differential electrical mobility analysis for aerosol

particles
ISO 29904:2013, Fire chemistry — Generation and measurement of aerosols
NIOSH Elemental carbon (diesel particulate): Method 5040, Issue 3
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 15900, ISO 29904 and the

following apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
diffusion flame

flame from a burner which gets its oxygen from the ambient surrounding air by diffusion and convection

mechanisms instead of having the oxygen forcibly premixed into the fuel
3.2
generation

process in which airborne particles are produced and injected into a defined airstream

3.3
mobility particle size
particle size provided by an electro‑static classifier

Note 1 to entry: The method is based on a principle that uses the forces exerted on charged particle in an electro‑

static field. The method is used for particles in the nm range and the classifier is typically combined with a

condensation particle counter to actually determine the concentration.
© ISO 2022 – All rights reserved
---------------------- Page: 6 ----------------------
ISO/DTS 12103-3:2022(E)
3.4
particle size distribution
number, mass or volume of particles as function of the particle size

Note 1 to entry: In this document the term is used for number distributions only. Particle size distributions may

have a wide variety of shapes but for the purpose of this document and application the distributions of soot (3.6)

particles can be assumed to be of a lognormal type.
3.5
particle number sizer

system consisting of a method to classify particles by electrical mobility and measures the number

concentration of particulate at each size through means of one or more condensation particle counters

and or electrometers
3.6
soot

particles from a combustion process consisting of carbon and being created during incomplete

incineration of organic fuels

Note 1 to entry: The particles start with clusters of several hundred carbon atoms and can form large grains up

to several hundred µm. Small soot particles have the tendency to agglomerate. A soot particle from combustions

consists of elemental carbon (EC) and organic carbon (OC). A lot of organic compounds are known and most of

them are bound on the EC‑agglomerates. Some of the organic compounds are carcinogenic like poly aromatic

hydrocarbon (PAH).
3.7
thermal-optical transmission

method to measure elemental carbon (EC) with its relationship to atmospheric soot (3.6)

Note 1 to entry: For the thermal‑optical transmission method (TOT), an emphasis on optical behaviour presents

it as a method for the accurate measurement of light-absorbing particulate carbon and thus allows EC to be

defined as black carbon (BC) as in the aethelometer.
4 Symbols and abbreviated terms
Symbol Explanation
µ mean value of a Gaussian standard distribution
σ standard deviation of a Gaussian standard distribution

σ geometric standard deviation (the logarithm of the GSD is the standard deviation)

geo
Abbreviations Explanation
Sub-micron particles < 1 µm
Super-micron particles > 1 µm
EC elemental carbon
OC organic carbon
TOT thermal-optical transmission
PAH poly aromatic hydrocarbons
© ISO 2022 – All rights reserved
---------------------- Page: 7 ----------------------
ISO/DTS 12103-3:2022(E)
5 Test contaminant
5.1 Definition

Test aerosols according to this document are generated by combustion of an organic fuel in the test lab.

They consist primarily of agglomerates of carbon particles where the primary carbon particles are on

the order of 20 nm diameter. Some organic compounds may be condensed on the carbon agglomerates

during the combustion and dilution processes. The amount of condensed organic material determines

the category of the test aerosol per 5.2.
5.2 Test contaminant designation

Soot contaminants are produced by burning a fuel (gas or liquid) and are listed in the grade as follows:

— ISO 12103‑3, S1 for ≥ 67 % carbon content.

This flame shall lead to an aerosol consisting of 70 % ± 3 % elemental carbon, 29 % ± 3 % organic carbon,

and < 1 % other substances. The air‑to‑fuel ratio of the flame shall be set as ± 10 % stoichiometric

balanced with adjustment of an inert mixing gas addition to the fuel flow to adjust the particle

distribution. The stoichiometric balance is described in Annex F.

Soot contaminant shall be tested per the methods in Annex E and the above requirements.

5.3 Generation of soot aerosol

Test aerosols according to this document are generated by combustion of an organic fuel in the test lab.

They consist primarily of agglomerates of carbon particles where the primary carbon particles are on

the order of 20 nm diameter. Organic compounds may be condensed on the carbon agglomerates during

the combustion and dilution processes.
5.4 Particle size distribution
The unimodal particle s
...

ISO TC 22/SC 34
Date: 2020-052022-09-16
ISO/TS 12103--3:20202022(E)
ISO TC 22/SC 34
Secretariat: ANSI

Road vehicles — Test contaminants for filter evaluation — Part 3: Soot contaminant

---------------------- Page: 1 ----------------------
ISO/DTS 12103-3:2022(E)
© ISO 2020 2022

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or

utilized in any form or by any means, electronic or mechanical, including photocopying and

microfilm, without permission in writing from either ISO at the address below or ISO's member

body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 734 10 79
E-mail [e-mail]
Web www.iso.ch
Printed in Switzerland
ii © ISO 2022 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/DTS 12103-3:2022(E)
Contents Page

Foreword ..............................................................................................................................................................................................5

Introduction ........................................................................................................................................................................................6

1 Scope .............................................................................................................................................................................................1

2 Normative references ............................................................................................................................................................1

3 Terms and definitions ...........................................................................................................................................................1

4 Symbols and abbreviated terms ........................................................................................................................................2

5 Test contaminant .....................................................................................................................................................................3

5.1 Definition ...........................................................................................................................................................................3

5.2 Test contaminant designation ..................................................................................................................................3

5.3 Generation of soot aerosol .........................................................................................................................................3

5.4 Particle size distribution .............................................................................................................................................3

5.5 Stability of aerosol concentration and particle size distribution ...............................................................3

5.6 Chemical composition ..................................................................................................................................................3

6 Analysis equipment and operating procedure ............................................................................................................4

6.1 General ...............................................................................................................................................................................4

6.2 Analysis equipment ......................................................................................................................................................4

6.3 Particle size analysis procedure ..............................................................................................................................4

6.4 Instrument calibration ................................................................................................................................................4

Annex A (normative) Particle size distributions by number .........................................................................................5

A.1 General ....................................................................................................................................................................................5

A.2 Lognormal distribution and Gaussian normal distribution ..............................................................................5

Figure A.1 — A typical particle size distribution curve of a real soot aerosol from a diffusion flame and an

engine .....................................................................................................................................................................................................7

Figure A.2 — Normal distribution with µ = 95 nm and σ = 1,75 ..............................................................................8

geo

A.3 Limits for acceptable distributions (Table A.1) .....................................................................................................8

Table A.1 — Limits and tolerances ............................................................................................................................................8

Annex B (informative) Handling and use of contaminant ..............................................................................................9

Table B.1 — Physical and safety data .......................................................................................................................................9

Table B.2 — Protective measures for storage and handling ...........................................................................................9

Table B.3 — Measures in case of accident or fire ................................................................................................................9

Table B.4 — Health aspects ..........................................................................................................................................................9

Annex C (informative) Concentration .................................................................................................................................. 10

Figure C.1 — Maximum number concentration ................................................................................................................ 11

Table C.1 — Half-life period for particle size distribution with mean value of 0,1 µm .................................... 11

Annex D (informative) Flame operation and morphology .......................................................................................... 13

D.1 Flame operation ............................................................................................................................................................... 13

Figure D.1 — Diffusion flame example ................................................................................................................................. 14

D.2 Morphology ........................................................................................................................................................................ 14

© ISO 2022 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO/DTS 12103-3:2022(E)

Figure D.2 — Soot from a diesel engine ............................................................................................................................... 14

Figure D.3 — Soot particles generated by a diffusion flame, using ethylene ........................................................ 15

Annex E (normative) Thermal-optical transmission analysis ................................................................................... 16

E.1 Description of the thermal-optical transmission analysis.............................................................................. 16

E.2 Description of filter, conditioning and storage ................................................................................................... 16

E.3 Description of sampling ................................................................................................................................................ 16

Annex F (informative) Air-to-fuel ratio ............................................................................................................................... 17

F.1 Description of the air-to-fuel ratio and example calculations ...................................................................... 17

Bibliography ..................................................................................................................................................................................... 18

iv © ISO 2022 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/DTS 12103-3:2022(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO

collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any

patent rights identified during the development of the document will be in the Introduction and/or on

the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the World

Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see

www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 22, Road Vehicles, Subcommittee

SC 34, Propulsion, powertrain and powertrain fluids.
A list of all parts in the ISO 12103 series can be found on the ISO website.

This second edition cancels and replaces the first edition (ISO 12103-3:2020), which has been technically

revised.
The main changes are as follows:
— modification to requirement regarding analysis equipment;
— modification to requirement regarding instrument calibration.
A list of all parts in the ISO 12103 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www.iso.org/members.html.
© ISO 2022 – All rights reserved v
---------------------- Page: 5 ----------------------
ISO/DTS 12103-3:2022(E)
Introduction

This document specifies a grade of test aerosol, which is composed of soot from a combustion source

similar to soot occurring in the environment that motor vehicles are commonly subjected to. This test

contaminant is developed for air filter media and element testing.

Ambient aerosols include at least two distinct modes of aerosol: a sub-micron mode and a super-micron

mode. Generally, the sub-micron mode comes from combustion sources or condensation of gases. The

super-micron mode comes from physical abrasion processes and wind-blown dust. The test dusts

described in ISO 12103-1 can be used to simulate the super-micron mode of ambient aerosol for testing

air filters. The soot aerosol described in this document is intended to simulate the sub-micron mode of

ambient aerosol.

There are several possible methods of generating soot aerosol, to simulate the sub-micron mode for air

filter testing purposes such as dispersing soot from a powder or using generated soot from a combustion

process.

Particle size of soot dispersed from bulk powder exceeds the environmental soot considerably.

For generated soot from a combustion process, a new procedure is described in this document. Using

aliphatic hydrocarbons, the soot consists of a combination of carbon, organic hydrocarbons and other

substances.
vi © ISO 2022 – All rights reserved
---------------------- Page: 6 ----------------------
TECHNICAL SPECIFICATION ISO/DTS 12103-3:2022(E)
Road Vehicles — Test Contaminant for Filter Evaluation — Part 3:
Soot Contaminant
1 Scope

This document defines particle size distribution by number and chemical content limits involving one

grade of test aerosol made from combustion soot.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

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.

ISO 15900, Determination of particle size distribution — Differential electrical mobility analysis for aerosol

particles
ISO 29904:2013, Fire chemistry — Generation and measurement of aerosols
NIOSH, Elemental carbon (diesel particulate): Method 5040, Issue 3
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 15900, ISO 29904 and the

following apply.

ISO and IEC maintain terminologicalterminology databases for use in standardization at the following

addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
3.1
diffusion flame

flame from a burner which gets its oxygen from the ambient surrounding air by diffusion and convection

mechanisms instead of having the oxygen forcibly premixed into the fuel
3.2
generation

process in which airborne particles are produced and injected into a defined airstream

3.3
mobility particle size
particle size provided by an electro-static classifier

Note 1 to entry: The method is based on a principle that uses the forces exerted on charged particle in an electro-

static field. The method is used for particles in the nm range and the classifier is typically combined with a

condensation particle counter to actually determine the concentration.
© ISO 2022 – All rights reserved 1
---------------------- Page: 7 ----------------------
ISO/DTS 12103-3:2022(E)
3.4
optical particle size

particle size as recorded by an optical particle sizing instrument or spectrometer

Note 1 to entry: The optical size differs in general from the physical size of a particle as it depends on particle

properties like the light diffraction index.
3.5
particle size distribution
number, mass or volume of particles as function of the particle size

Note 1 to entry: In this document the term is used for number distributions only. Particle size distributions may

have a wide variety of shapes but for the purpose of this document and application the distributions of soot (3.76)

particles can be assumed to be of a lognormal type.
3.65
particle number sizer

system consisting of a method to classify particles by electrical mobility and measures the number

concentration of particulate at each size through means of one or more condensation particle counters

and or electrometers
3.76
soot

particles from a combustion process consisting of carbon and being created during incomplete

incineration of organic fuels

Note 1 to entry: The particles start with clusters of several hundred carbon atoms and can form large grains up to

several hundred µm. Small soot particles have the tendency to agglomerate. SootA soot particle from combustions

consists of elemental carbon (EC) and organic carbon (OC). A lot of organic compounds are known and most of them

are bound on the EC-agglomerates. Some of the organic compounds are carcinogenic like poly aromatic

hydrocarbon (PAH).
3.87
thermal-optical transmission

method to measure elemental carbon (EC) with its relationship to atmospheric soot (3.76)

Note 1 to entry: For the thermal-optical transmission method (TOT), an emphasis on optical behaviorbehaviour

presents it as a method for the accurate measurement of light-absorbing particulate carbon and thus allows EC to

be defined as black carbon (BC) as in the aethelometer.
4 Symbols and abbreviated terms
Symbol Explanation
µ mean value of a Gaussian standard distribution
σ standard deviation of a Gaussian standard distribution

σ geometric standard deviation (the logarithm of the GSD is the standard deviation)

geo
Abbreviations Explanation
Sub-micron particles < < 1 µm
Super-micron particles > > 1 µm
EC elemental carbon
OC organic carbon
2 © ISO 2022 – All rights reserved
---------------------- Page: 8 ----------------------
ISO/DTS 12103-3:2022(E)
TOT thermal-optical transmission
PAH poly aromatic hydrocarbons
5 Test contaminant definition
5.1 Definition

Test aerosols according to this document are generated by combustion of an organic fuel in the test lab.

They consist primarily of agglomerates of carbon particles where the primary carbon particles are on the

order of 20 nm diameter. Some organic compounds may be condensed on the carbon agglomerates

during the combustion and dilution processes. The amount of condensed organic material determines

the category of the test aerosol per 5.12.
5.15.2 Test contaminant designation

Soot contaminants are produced by burning a fuel (gas or liquid) and are listed in the grade as follows:

— ISO 12103--3, S1 for ≥ ≥ 67 % carbon content.

This flame shall lead to an aerosol consisting of 70 % ± ± 3 % elemental carbon, 29 % ± ± 3 % organic

carbon, and < < 1 % other substances. The air-to-fuel ratio of the flame shall be set as ± ± 10 %

stoich
...