ISO 8178-2:2021

Reciprocating internal combustion engines — Exhaust emission measurement — Part 2: Measurement of gaseous and particulate exhaust emissions under field conditions

This document specifies the measurement and evaluation methods for gaseous and particulate exhaust emissions from reciprocating internal combustion engines (RIC engines) in the field. This document is applicable when the emissions from RIC engines used in non-road machinery, industrial equipment, marine installations, generating sets, diesel rail traction or similar machinery applications need to be measured in the field. Clause 4 applies for the conduct of discrete-mode steady-state gaseous or particulate emission measurements at a single operating point or conduct a weighted cycle-based test in the field. Clause 5 applies where it is necessary to assess gaseous emissions performance of engines during typical in-service operation under field conditions using portable emission measurement systems (PEMS).

Moteurs alternatifs à combustion interne — Mesurage des émissions de gaz d'échappement — Partie 2: Mesurage des émissions de gaz et de particules sur site

Le présent document spécifie les méthodes de mesure et d'évaluation sur site des émissions de gaz et de particules des gaz d'échappement des moteurs alternatifs à combustion interne sur site. Le présent document est applicable lorsque les émissions des moteurs alternatifs à combustion interne utilisés dans des engins non routiers, des équipements industriels, des installations marines, des groupes électrogènes, des applications à la traction ferroviaire diesel ou similaires, font l'objet de mesurages sur site. L’Article 4 s’applique à la réalisation de mesures d’émissions de gaz ou de particules des gaz d'échappement en régime permanent de type discret en un point de fonctionnement unique ou à celle d’un essai basé sur un cycle pondéré sur site. L’Article 5 s’applique lorsqu'il est nécessaire d’évaluer les performances d’émissions de gaz des moteurs au cours du fonctionnement normal sur site en utilisant des systèmes de mesure des émissions de type portable (PEMS).

General Information

• Status: Published
• Publication Date: 22-Dec-2021
• ICS: 13.040.50 - Transport exhaust emissions
• ICS: 27.020 - Internal combustion engines
• Technical Committee: ISO/TC 70/SC 8 - Exhaust gas emission measurement
• Drafting Committee: ISO/TC 70/SC 8/WG 6 - Test bed measurement
• Current Stage: 6060 - International Standard published
• Start Date: 23-Dec-2021
• Due Date: 21-Jun-2021
• Completion Date: 23-Dec-2021

Relations

• Revises: ISO 8178-2:2008 - Reciprocating internal combustion engines — Exhaust emission measurement — Part 2: Measurement of gaseous and particulate exhaust emissions under field conditions
• Effective Date: 10-Mar-2018

Standards Content (Sample)

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 8178-2
ISO/TC 70/SC 8
Reciprocating internal combustion
Secretariat: DIN
engines — Exhaust emission
Voting begins on:
2021-07-23 measurement —
Voting terminates on:
Part 2:
2021-09-17
Measurement of gaseous and
particulate exhaust emissions under
field conditions
Moteurs alternatifs à combustion interne — Mesurage des émissions
de gaz d'échappement —
Partie 2: Mesurage des émissions de gaz et de particules sur site
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/FDIS 8178-2:2021(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 2021
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ISO/FDIS 8178-2:2021(E)
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ii © ISO 2021 – All rights reserved
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ISO/FDIS 8178-2:2021(E)
Contents Page

Foreword ..........................................................................................................................................................................................................................................v

Introduction ................................................................................................................................................................................................................................vi

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

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

3 Terms, definitions, symbols and abbreviated terms ....................................................................................................... 2

3.1 Terms and definitions ....................................................................................................................................................................... 2

3.2 Symbols ......................................................................................................................................................................................................... 3

3.2.1 General symbols ............................................................................................................................................................... 3

3.2.2 Symbols for measured chemical components ........................................................................................ 3

3.3 Abbreviated terms ............................................................................................................................................................................... 4

4 Discrete-mode steady-state tests in the field when it is intended to either conduct

measurements at a single operating point or conduct a weighted cycle-based test ......................4

4.1 General ........................................................................................................................................................................................................... 4

4.2 Test conditions ........................................................................................................................................................................................ 4

4.2.1 General requirements .................................................................................................................................................. 4

4.2.2 Engine test conditions ................................................................................................................................................. 4

4.2.3 Power ......................................................................................................................................................................................... 5

4.2.4 Engine air intake system ........................................................................................................................................... 5

4.2.5 Charge air cooler .............................................................................................................................................................. 5

4.2.6 Engine exhaust system ............................................................................................................................................... 5

4.2.7 Engines with exhaust after-treatment systems .................. ................................................................... 6

4.2.8 Crankcase emissions..................................................................................................................................................... 6

4.2.9 Cooling system ................................................................................................................................................................... 6

4.2.10 Lubricating oil .................................................................................................................................................................... 6

4.2.11 Test fuels ................................................................................................................................................................................. 6

4.3 Installation of sampling probes and equipment ........................................................................................................ 6

4.4 Measurement equipment and data to be measured ............................................................................................... 7

4.4.1 General...................................................................................................................................................................................... 7

4.4.2 Zirconium dioxide (ZRDO) NOx analyser ................................................................................................... 7

4.4.3 Alternative measurement procedures .......................................................................................................... 8

4.4.4 Torque and speed ............................................................................................................................................................ 8

4.4.5 Exhaust gas flow ............................................................................................................................................................... 8

4.4.6 Accuracy of the data to be measured ............................................................................................................. 9

4.4.7 Determination of the gaseous components .............................................................................................. 9

4.4.8 Determination of the particulates ..................................................................................................................... 9

4.5 Running conditions ..........................................................................................................................................................................10

4.5.1 Test cycles ...........................................................................................................................................................................10

4.5.2 Preparation of the engine ......................................................................................................................................10

4.6 Test run .......................................................................................................................................................................................................10

4.6.1 General...................................................................................................................................................................................10

4.6.2 PM measurement..........................................................................................................................................................10

4.6.3 Dilution air for particulate measurement ...............................................................................................10

4.6.4 Test sequence .................. .................................................... .............................................................................................11

4.6.5 Gas analyser drift validation and correction ........................................................................................11

4.6.6 Emissions evaluation and calculation ........................................................................................................11

4.6.7 Test report ..........................................................................................................................................................................11

5 Measurement of gaseous emissions performance of engines during typical in-
service operation under field conditions using portable emission measurement

systems (PEMS) ...................................................................................................................................................................................................11

5.1 Test conditions .....................................................................................................................................................................................11

5.1.1 General requirements ...............................................................................................................................................11

5.1.2 Selection of engine for assessment of design performance .....................................................12

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ISO/FDIS 8178-2:2021(E)

5.1.3 Machinery operation .................................................................................................................................................12

5.1.4 Ambient conditions ....................................................................................................................................................13

5.1.5 Lubricating oil, fuel and reagent .....................................................................................................................13

5.1.6 Operating sequence ....................................................................................................................................................13

5.2 Data sampling methods ................................................................................................................................................................13

5.2.1 Continuous data sampling ....................................................................................................................................13

5.2.2 Combined data sampling .......................................................................................................................................13

5.2.3 Temporary signal loss...............................................................................................................................................14

5.3 ECU data stream ......... .........................................................................................................................................................................14

5.3.1 General...................................................................................................................................................................................14

5.3.2 Verification of availability and conformity of information .......................................................15

5.4 Test procedures ...................................................................................................................................................................................15

5.5 Data pre-processing .........................................................................................................................................................................15

5.6 Determination of working events ........................................................................................................................................15

5.6.1 General...................................................................................................................................................................................15

5.6.2 Combining operating sequences .....................................................................................................................15

5.7 Test data availability .......................................................................................................................................................................15

5.8 Calculations .............................................................................................................................................................................................15

5.8.1 General...................................................................................................................................................................................15

5.8.2 Engines without communication interface ............................................................................................15

5.9 Test report ................................................................................................................................................................................................16

5.10 Instantaneous measured data file and instantaneous calculated data file ......................................16

5.11 Overview of measurement and evaluation sequence .........................................................................................16

Annex A (normative) Portable Emissions Measurement System (PEMS) ...................................................................18

Annex B (normative) Test procedure for gaseous emission measurement with a PEMS ...........................20

Annex C (normative) Determination of reference work and CO for engines for which the

applicable bench test cycle is solely NRSC ..............................................................................................................................27

Annex D (normative) Data pre-processing for gaseous pollutant emissions calculations .......................29

Annex E (normative) Algorithm for the determination of working events during in-service

testing ...........................................................................................................................................................................................................................34

Annex F (normative) Determination of the instantaneous proxy power from CO mass flow rate .40

Annex G (normative) Gaseous pollutant emissions calculations.........................................................................................42

Annex H (normative) Conformity of the ECU torque signal .......................................................................................................49

Annex I (normative) ECU data stream information requirements ....................................................................................50

Annex J (informative) Test report for in-service testing ...............................................................................................................52

Annex K (normative) Performance specifications, calibration and response factor for

Zirconium Dioxide (ZRDO) NOx analyser ................................................................................................................................59

Bibliography .............................................................................................................................................................................................................................61

iv © ISO 2021 – All rights reserved
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ISO/FDIS 8178-2:2021(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 70, Internal combustion engines,

Subcommittee SC 8, Exhaust gas emission measurement.

This third edition cancels and replaces the second edition (ISO 8178-2:2008), which has been technically

revised.
The main changes compared to the previous edition are as follows:

— Clause 4 has been amended to update requirements applicable for discrete-mode steady-state tests

in the field when it is intended to either conduct measurements at a single operating point or conduct

a weighted cycle-based test, reflecting changes in other parts of the ISO 8178 series;

— Clause 5 has been expanded to set out requirements for measurement of gaseous emissions

performance of engines during typical in-service operation under field conditions using portable

emission measurement systems (PEMS) and moving average window data evaluation.
A list of all parts in the ISO 8178 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 2021 – All rights reserved v
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ISO/FDIS 8178-2:2021(E)
Introduction

Evaluating emissions from non-road engines is more complicated than the same task for on-road

engines due to the diversity of non-road applications. For example, on-road applications primarily

consist of moving a load from one point to another on a paved roadway. The constraints of the paved

roadways, maximum acceptable pavement loads and maximum allowable grades of fuel, narrow the

scope of on-road vehicle and engine sizes.

Non-road engines and vehicles include a wider range of size, including size of the engines that power

the equipment. Many of the engines are large enough to preclude the application of test equipment

and methods that were acceptable for on-road purposes. In cases where a laboratory test using a

dynamometer is not possible, testing at site or under appropriate conditions can be a viable alternative.

Where it is not possible to use a test bed or where information is required on the actual emissions

produced by an in-service engine, the site test procedures and calculation methods specified in

ISO 8178-2 are appropriate. It should be recognized that data obtained under these circumstances may

not agree completely with previous or future data, obtained in a laboratory or in the field, due to the

variability and uncontrolled nature of testing in the field.
vi © ISO 2021 – All rights reserved
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 8178-2:2021(E)
Reciprocating internal combustion engines — Exhaust
emission measurement —
Part 2:
Measurement of gaseous and particulate exhaust
emissions under field conditions
1 Scope

This document specifies the measurement and evaluation methods for gaseous and particulate exhaust

emissions from reciprocating internal combustion engines (RIC engines) in the field.

This document is applicable when the emissions from RIC engines used in non-road machinery,

industrial equipment, marine installations, generating sets, diesel rail traction or similar machinery

applications need to be measured in the field. Clause 4 applies for the conduct of discrete-mode steady-

state gaseous or particulate emission measurements at a single operating point or conduct a weighted

cycle-based test in the field. Clause 5 applies where it is necessary to assess gaseous emissions

performance of engines during typical in-service operation under field conditions using portable

emission measurement systems (PEMS).
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 8178-1:2020, Reciprocating internal combustion engines — Exhaust emission measurement — Part 1:

Test-bed measurement systems of gaseous and particulate emissions

ISO 8178-4, Reciprocating internal combustion engines — Exhaust emission measurement — Part 4:

Steady-state and transient test cycles for different engine applications

ISO 8178-5, Reciprocating internal combustion engines — Exhaust emission measurement — Part 5: Test

fuels

ISO 8178-6, Reciprocating internal combustion engines — Exhaust emission measurement — Part 6:

Report of measuring results and test

ISO 17025, General requirements for the competence of testing and calibration laboratories

ISO 27145, Road vehicles — Implementation of World-Wide Harmonized On-Board Diagnostics (WWH-

OBD) communication requirements

ISO 15765-4, Road vehicles. Diagnostic communication over Controller Area Network (DoCAN).

Requirements for emissions-related systems

ISO 13400, Road vehicles — Diagnostic communication over Internet Protocol (DoIP)

ISO 15031-3, Road vehicles — Communication between vehicle and external equipment for emissions-

related diagnostics — Part 3: Diagnostic connector and related electrical circuits: Specification and use

SAE J1939-73, Application layer – diagnostics
© ISO 2021 – All rights reserved 1
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ISO/FDIS 8178-2:2021(E)

ASTM E 29-06b, Standard Practice for Using Significant Digits in Test Data to Determine Conformance

with Specifications
3 Terms, definitions, symbols and abbreviated terms
3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 8178-1, ISO 8178-4 and the

following apply.

ISO and IEC maintain terminological 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/
3.1.1
event

data measured in an in-service test for the gaseous pollutant emissions calculations obtained in a time

increment Δt equal to the data sampling period
3.1.2
field conditions

conditions under which the engine under test is installed in, and coupled with, the actual equipment or

vehicle, which is driven by the engine, and conditions under which the equipment or vehicle is allowed

to function in normal use
3.1.3
moving average window

period, measured in cumulative amount of work or CO , over which each integration of gaseous

pollutant emissions is performed
3.1.4
operating sequence

elapsed time of uninterrupted machinery operation and continuous data sampling during an in-service

test
3.1.5
portable emission measurement system
PEMS

emission measurement system that is transportable and suitable for conducting in-service

measurements
3.1.6
proxy power

value obtained by simple linear interpolation based on certain assumptions for the sole purpose of

identifying non-working events when there is no torque signal from an Electronic Control Unit (ECU)

3.1.7
reference mass of CO

amount of cumulative CO measured during a prior bench-test of the engine type or, where applicable,

engine family, which is used to determine the size of the moving average CO window

3.1.8
reference work

amount of cumulative work measured during a prior bench-test of the engine type or, where applicable,

engine family, which is used to determine the size of the moving average work window

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ISO/FDIS 8178-2:2021(E)
3.2 Symbols
3.2.1 General symbols
Symbol Term Unit
D Maximum averaging window duration s
max
e Brake specific gaseous pollutant emissions g/kWh
gas
f Laboratory atmospheric factor —
f Conformity factor —
f Certification ratio —
CFC
f In-service ratio —
CFI
f Weighting factor —
K Simplified engine-family-specific CO constant —
veline 2
L Limit value g/kWh
m Mass emission of gaseous pollutant g
m Mass of CO for the test cycle g
CO2 2
m Reference mass of CO g
CO2ref 2
N Number of mode in test cycle —
mode
p Total barometric pressure kPa
p Dry atmospheric pressure kPa
P Uncorrected brake power kW

Declared total power absorbed by auxiliaries fitted for the test and not required by Annex B

P kW
aux
of ISO 8178-4:2020
P Maximum measured or declared power kW
max
P Instantaneous proxy power (see Annex F) kW
proxy,i
P Measured power kW
q Mean CO mass flow rate g/h
mCO2 2
r NO response factor of zirconium dioxide analyser —
NOx x
r NO response factor of zirconium dioxide analyser —
NO2 2
r Maximum NO /NO concentration ratio —
NO2,max 2 x
t Time s
t Reference time s
ref
T Temperature °C
Ta Absolute temperature K
W Work kWh
W Actual work kWh
act
W Reference work kWh
ref
3.2.2 Symbols for measured chemical components
Symbol Component
CO Carbon monoxide
CO Carbon dioxide
HC Hydrocarbons
NH Ammonia
NMHC Non-methane hydrocarbons
NO Nitrogen Dioxide
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ISO/FDIS 8178-2:2021(E)
Symbol Component
NO Oxides of nitrogen
PM Particulate matter
PN Particulate number
THC Total hydrocarbons
3.3 Abbreviated terms
ECU Electronic Control Unit
EFM Exhaust Flow Meter
LSI-NRTC Large Spark-Ignition Non-Road Transient Cycle
NRMM Non-Road Mobile Machinery
NRSC Non-Road Steady-State Cycle
NRTC Non-Road Transient Cycle
RMC NRSC Ramped Modal Non-Road Steady-State Cycle
ZRDO Zirconium dioxide (analyser)
4 Discrete-mode steady-state tests in the field when it is intended to either
conduct measurements at a single operating point or conduct a weighted cycle-
based test
4.1 General

Testing conducted according to Clause 4 shall in general follow the requirements set out in

ISO 8178-1:2020 and ISO 8178-4 for discrete-mode steady-state testing. Deviations from the

requirements of those parts are limited to those set-out in Clause 4. This clause shall not be used for

transient testing.
4.2 Test conditions
4.2.1 General requirements

Field measurements according to Clause 4 shall be conducted only when test-bed measurement is not

appropriate because the required measurement cannot be performed on the test-bed.

NOTE When testing under field conditions the test cycles specified in ISO 8178-4:2020 might not be fully

reproduceable, there might be differences in engine operating parameters from laboratory conditions and there

might be differences in the accuracy of emission measurement equipment. Consequently, it is not expected that

the emission results obtained when testing according to Clause 5 will be directly comparable to the values

obtained on the test bed.
4.2.2 Engine test conditions
4.2.2.
...