EN   EN 
 
 
 EUROPEAN  
COMMISSION   
Brussels, XXX   
[…](2021) XXX  draft  
ANNEX  
 
ANNEX  
to the  
COMMISSION DELEGATED REGULATION (EU) .../...  
amending Delegated Regulation (EU) 2017/655 as regards the adaptation of the 
provisions on monitoring of gaseous pollutant emissions from in -service internal 
combustion engines installed in non -road mobile machinery to engines with power of 
less than 56 kW  and more than 560 kW   EN 1  EN ANNEX  
The Annex to Delegated Regulation (EU) 2017/655 is amended as follows:  
(1) The following point s 1.2.a and 1.2.b are  inserted  after point 1.2 : 
1.2.a.  In-Service Monitoring Engine Grouping (ISM Group)  
For the carrying out of in-service testing , all engine types and engine families produced by the 
manufacturer shall be grouped in accordance with its sub -category as set out in Table 1 and 
illustrate d in Figure 1 . One manufacturer may have one ISM Group for each possible type of 
ISM Group . 
Table 1  
ISM Groups  
ISM Group  Engine (sub -)categories  
A NRE -v-5, NRE -v-6 
B NRE -c-5, NRE -c-6 
C NRE -v-3, NRE -v-4 
D NRE -c-3, NRE -c-4 
E NRE -v-1, NRE -c-1, NRE -v-2, NRE -c-2 
F NRE -v-7, NRE -c-7 
G NRG -v-1, NRG -c-1 
H NRS -v-2b, NRS -v-3 
I NRS -vr-1b, NRS -vi-1b, NRS -v-2a 
J IWP-v-1, IWP -c-1, IWA -v-1, IWA -c-1, IWP -v-2, IWP -c-2, IWA -v-2, IWA -c-
2 
K IWP-v-3, IWP -c-3, IWA -v-3, IWA -c-3 
L IWP-v-4, IWP -c-4, IWA -v-4, IWA -c-4 
M RLL -v-1, RLL -c-1 
N RLR -v-1, RLR -c-1 
O SMB -v-1 
P ATS -v-1 
 
  EN 2  EN Figure 1  
Illustration of ISM G roups  
 
 
1.2.b.  The approval authority ensu ring the compliance with this Regulation shall be 
either:  
a) the approval authority  that granted the type -approval of the engine type or 
engin e  family, in case that the ISM G roup contains a single type -approval;  
b) the approval authority  that granted the type -approval of several engine types 
and/or  engine families within the same ISM Group;  
c) in the case that the ISM G roup contains engine types, and/or engine 
 families, approved by different approval authorities, the approval authority 
 designated by all approval authorities involved  
(2) in point 1.3, sub-point (b) is deleted:  
(3) point 1.4 is rep laced by the following:  
‘1.4.  Engines with an Electronic Control Unit ( ECU ) and a communication interface 
intended to provide the necessary data as specified in Appendix 7 but with a 
missing interface  or missing data, or where it is not possible to achiev e clear 
identification and validation of the necessary signals, shall not be eligible for in -
service monitoring test, and an alternative engine shall be selected.  
The approval authority shall not accept the absence of an ECU or interface, or 
absent or inva lid signals, or lack of conformity of the ECU torque signal, as a 
reason to reduce the number of engines to be tested under this Regulation .’; 
(4) point 2.1 is replaced by the following:  
‘2.1.  The manufacturer shall submit the initial plan for monitoring each ISM Group to 
the approval authority within:  
EN 3  EN (a)  for ISM Group A, one month of the start of production of any engine type or 
engine family  within the ISM Group ;  
(b)  for any other ISM Group, the later date of the following : 
(i) [Please OJ insert the date six months after the  day of  entry into force of th is 
Regulation ]; 
(ii) 1 month after the start of production of any engine type or engine family  
within the ISM Group .’; 
(5) in point 2.2. , the introduc tory sentence is replaced by the following:  
‘2.2. The initial plan shall include the list of engine types and engine families in the 
ISM Group, together with the criteria used for and the justification of the selection 
of:’; 
(6) point 2.3 is replaced by the fo llowing : 
‘2.3.  Manufacturers shall submit to the approval authority an updated plan 
for monitoring in -service engines whenever the list of engine families in the 
ISM Group changes or the list of particular engine(s) and non -road mobile 
machinery selected is completed or revised. The updated plan shall include a 
justification of the criteria used for the selection and the reasons for revising 
the previous list, if applicable. Where the number of engine families in the ISM 
Group or the annual production volu me for the Union market changes , the 
number of tests to be executed in accordance with  point 2.7 , the plan shall also 
be adjusted accordingly. ’; 
(7) Points 2.6 to 2.6.4 are replaced by the following:  
‘2.6. Criteria for selection of engines to be tested  
The number of engines to be tested refers to the ISM group , and not to the engine 
sub-categories, engine families or engine types belonging to ISM group.  
The manufacturer shall select engines that represent , in a balanced manner , the 
sub-categories, engine fa milies and engine types belonging to the ISM group. This 
should not  necessarily  imply testing engines belonging to each engine sub -
category, engine family or engine type.  
For ISM groups containing both category IWP and IWA the engine selection shall 
includ e, to the extent possible , engines of both categories.  
2.6.1.  Testing scheme for ISM group A  
 The manufacturer shall choose one of the following testing schemes described in 
points 2.6.1.1 and in 2.6.1.2 for in -service monitoring.  
2.6.1.1.  Testing scheme based on the Emission Durability Period (EDP)  
2.6.1.1.1  Testing 9 engines from the ISM group with an accumulated service of less than a 
% of the EDP, in accordance with Table 2. Test results shall be submitted to the 
approval authority by [Please OJ inse rt the date twenty -four months after the day 
of entry into force of this Regulation ]. 
2.6.1.1.2.  Testing 9 engines from the ISM group with an accumulated service higher than b 
% of the EDP, in accordance with Table 2. Test reports shall be submitted to th e 
approval authority by [Please OJ insert the date forty -eight months after the day 
of entry into force of this Regulation ].  EN 4  EN 2.6.1.1.3.  When the manufacturer cannot fulfil the requirement under point 2.6.1.1 due to 
unavailability of engines with the requ ired service accumulation of point 2.6.1.1.2, 
the approval authority may permit testing of engines under this point with an 
accumulated service between 2 times a % and b % of the EDP, subject to the 
manufacturer providing robust evidence that they have sel ected engines with the 
highest available service accumulation. As an alternative, the approval authority 
shall accept a change to the testing scheme based on a 4 -year period set out in 
point 2.6.1.2. In th at case, the total number of engines to be tested under point 
2.6.1.2 shall be reduced by the number of engines already tested and reported in 
accordance with point 2.6.1.1.  
Table 2  
% of EDP values  for ISM group defined in 2.6.1  
Reference power of selected engine 
(kW)  a b 
56 ≤ P < 130  20 55 
130 ≤ P ≤ 560  30 70 
 
2.6.1.2.  Testing scheme based on a 4 -year period  
Every manufacturer shall test an  average of nine engines per year from the ISM 
group during 4 consecutive years . To the extent possible, also test reports shall be 
submitted to the approval authority every year . The schedule for testing and 
submitting results shall be included in the initial plan, and in any subsequently 
updated plan, for monitoring in -service engines submitted by the manufacturer 
and approved by the approval authority.  
2.6.1.2.1.  The test results of the first nine engines shall be submitted not later than 24 
months after the first engine was installed in non -road mobile machinery and not 
later than 30 months after starting the produ ction of an approved engine type or 
engine family within the ISM group.  
2.6.1.2.2.  Whe re the manufacturer demonstrates to the approval authority that no engine has 
been installed in non -road mobile machinery 30 months after starting the 
production, the te st results shall be submitted after the installation of the first 
engine, on a date agreed with the approval authority.  
2.6.1.2.3.  Small -volume manufacturers  
The number of engines tested shall be adapted in case of small -volume 
manufacturers  as follows :  
(a)  manufacturers producing only two engine families within an ISM group 
shall submit an average of six engine test results per year;  
(b)  manufacturers producing for the Union market more than 250 engines per 
year of an ISM group containing only one single engine family shall submit 
an average of three engine  test results per year;  EN 5  EN (c)  manufacturers producing for the Union market between 1 25 and 250 
engines per year of an ISM group containing only one single engine family 
shall submit  an average of  two engine's test results per year;  
(d)  manufacturers producing for the Union market fewer than 125 engines per 
year of an ISM group containin g only one single engine family shall submit 
an average of one engine's test results per year.  
The approval authority shall verify the declared production quantities are not 
exceeded during the 4-year period that the manufacturer conducts testing. If thes e 
quantities are exceeded at any point , the manufacturer shall test an average of nine 
engines per year for the remaining years of the 4-4year period for which results 
have not been reported.  
2.6.2.  Testing scheme for ISM groups B, F, G, J, K, L, M and N  
 The manufacturer shall choose , for each group , one of the following testing 
schemes described in points 2.6.2.1 and in 2.6.2.2 for in -service monitoring.  
2.6.2.1.  Testing scheme based on the Emission Durability Period (EDP)  
2.6.2.1.1.  Testing x engines fro m the ISM group with an accumulated service of less than c 
% of the EDP, in accordance with Table 3. Test results shall be submitted to the 
approval authority by [Please OJ insert the date twenty -four months after the day 
of entry into force of this Regula tion]. 
2.6.2.1.2.  Testing x engines from the ISM group with an accumulated service higher than d 
% of the EDP, in accordance with Table 3. Test results shall be submitted to the 
approval authority by [Please OJ insert the date forty -eight months after the day 
of entry into force of this Regulation ]. 
2.6.2.1.3.  When the manufacturer cannot fulfil the requirement s set out in  point s 2.6.2.1 .1 
and 2.6.2.1.2  due to unavailability of engines with the required service 
accumulation, the approval authority may permi t testing of engines under this 
point with an accumulated service between 2 times c % and d % of the EDP, 
subject to the manufacturer providing robust evidence that they have selected 
engines with the highest available service accumulation. As an alternati ve, the 
approval authority shall accept a change to the testing scheme based on a 4 -year 
period set out in point 2.6.2.2. In th at case, the total number of engines to be tested 
under point 2.6.2.2 shall be reduced by the number of engines already tested an d 
reported in accordance with point s 2.6.2.1 .1 and 2.6.2.1.2 . 
2.6.2.1.4.  When the test report of a Stage IIIB engine family equivalent to category RLL is 
used to obtain a corresponding Stage V type -approval for that engine family in 
accordance with  Article 7(2) of Implementing Regulation (EU) 2017/656 and the 
engine manufacturer cannot fulfil the requirement s under point s 2.6.2.1 .1 and 
2.6.2.1.2  due to unavailability of Stage V engines with the required service 
accumulation, the approval authority shall acc ept the selection of a Stage IIIB 
engine to comply with the requirements of  point s 2.6.2.1.1 and 2.6.2.1.2 . 
  EN 6  EN Table 3  
% of EDP values for ISM group s defined in 2.6.2 .1 
Reference power of selected 
engine (kW)  c d 
P < 56  10 40 
56 ≤ P < 130  20 55 
P ≥ 130  30 70 
 
Table 4  
Number of engines to be tested for ISM group s defined in 2.6.2  and 2.6.3.1  
 N CA x 
1 - 1 
2 ≤ N ≤4  - 2 
> 4 ≤ 50 2 
5 ≤ N ≤6  > 50 3 
≥ 7 > 50 4 
Where:  
N = Total number of EU engine families produced by the manufacturer within 
the ISM group  
CA = Combined annual production for EU market for the remaining engine 
families produced by manufacturer within group after discarding the four 
families with the highest annual production for EU market.  
x = Number of engines to be tested  
 
2.6.2.2.  Testing scheme based on a 4 -year period  
 Testing an average of x engines from the ISM group per year during 4 consecutive 
years, in accordance with Table 4. Test reports shall be submitted to the approval 
authority every year  and the years shall be consecu tive. The schedule for testing 
and submitting results shall be included in the initial plan, and in any subsequently 
updated plan, for monitoring in -service engines submitted by the manufacturer 
and approved by the approval authority . 
2.6.2.2.1.  The test r esults of the first x engines shall be submitted before the later  date of the 
following : 
(a) [Please OJ insert the date twenty -four months after the day of entry into force 
of this Regulation ]; EN 7  EN (b) 12 months after the first engine was installed innon -road mobile machinery;  
(c) 18 months after starting the production of an approved engine type or engine 
family within the ISM group.  
2.6.2.2.2.  When the manufacturer demonstrates to the approval authority that no engine has 
been installed in non -road mobile mac hinery 18 months after starting the 
production, the test results shall be submitted after the installation of the first 
engine, on a date agreed with the approval authority.  
2.6.2. 2.3.  Small -volume manufacturers  
 The number of engines tested shall be adap ted in case that the combined annual 
production across all engine families in an ISM group does not exceed 50 engines 
(small volume manufacturers) , as follows : 
(a) manufacturers producing a total between 25 and 50 engines per year for the 
Union market acro ss all families in a given ISM group shall submit either:  
(i)  one engine test results with an accumulated service between c % and d 
% of EDP as defined in Table 3 by [Please OJ insert the date thirty -six 
months after the day of entry into force of this R egulation ], or; 
(ii) an average of one engine test results per year over 2 years , starting  12 
months after the first engine was installed in non -road mobile machinery ,  
(b)  manufacturers producing a total of fewer than 25 engines per year for the EU 
market across all families in a given ISM group need not submit any engine 
test unless the production exceeds 35 engines in a two -year rolling period , in 
which case the manufacturer shall follow the same scheme as set out in sub -
point (a).  
The approval aut hority shall verify  that the declared production quantities are not 
exceeded during the periods set out in the first paragraph, sub-point (a). If th ose 
quantities are exceeded at any point , the manufacturer shall change to one of the 
testing schemes set  out in points 2.6.2.1 . and 2.6.2.2. In that case, the total number 
of engines to be tested under those points shall be reduced by the number of 
engines already tested and reported in accordance with this point.  
2.6.3 . ISM groups C, D, E, H and I  
 The manufac turer shall choose , for each group , one of the testing schemes 
described in point 2.6.2 or the testing scheme based on age of equipment 
described in section 2.6.3.1 for in -service monitoring.  
2.6.3.1. Testing scheme based on the age of non -road mobile mach inery  (see Figure 2 for 
reference)  
2.6.3.1.1 . Testing x engines from the ISM group with non -road mobile machinery 
production year not more than 2 years prior to the date of that test , (see Figure 2), 
in accordance with Table 4. Test results shall be submit ted to the approval 
authority by [Please OJ insert the date twenty -four months after the day of entry 
into force of this Regulation ].  
2.6.3.1.2.  Testing x engines from the ISM group with non -road mobile machinery 
production year not less than 4 years prior to year of test , (see Figure 2), in 
accordance with Table 4. Test results shall be submitted to the approval authority EN 8  EN by [Please OJ insert the date forty -eight months after the day of entry into force of 
this Regulation ]. 
2.6.3.1.2.1.  Robust evidence shall be provided to the approval authority that each engine 
selected for testing under point 2. 6.3.1.2 has been used each year in a manner and 
to an extent similar to that of the population of corresponding engines placed on 
the Union mark et. Suitable evidence may include characteristics demonstrating 
normal wear, records of use, records of maintenance and records of fuel 
consumed.  
2.6.3.1.3.  When the manufacturer cannot fulfil the requirement s set out in point s 2.6.3.1.1 
and 2.6.3.1.2  due to unavailability of engines with the required non -road mobile 
machinery production year or insufficient evidence of use, the approval authority 
shall accept a change to the testing scheme based on a 4-year period set out in 
point 2. 6.2.2. In th at case, t he total number of engines to be tested under point 
2.6.2.2 shall be reduced by the number of engines already tested and reported in 
accordance with point s 2.6.3.1.1 and 2.6.3.1.2 .  
Figure 2  
Illustration of eligible engines for ISM test based on age of non-road mobile 
machinery  
 
2.6.4.  ISM group s O and  P 
 The manufacturer shall choose , for each group , one of the testing schemes 
described in point 2.6.2 or the testing scheme based on the odometer reading 
described in point 2.6.4.1 for in -service monitor ing. 
 In case that the manufacturer choses the procedure set out in point 2.6.2.1, the 
required accumulated service shall be the one stated in Table 5 instead of the one 
stated in Table 3.  
 
EN 9  EN  
 
 
 Table 5  
% of EDP values for ISM groups O and P  
Group  c d 
O 20 55 
P 10 40 
 
2.6.4.1. Testing scheme based on the odometer reading of non -road mobile machinery  
2.6.4.1.1.  Testing x engines from the ISM group with non -road mobile machinery odometer 
reading an accumulated service of less than c (km) in accordance with Table 6. 
Test results shall be submitted to the approval authority by  [Please OJ insert the 
date twenty -four months after the day of entry into force of this Regulation ]. 
2.6.4.1.2.  Testing x engines from the ISM group with non -road mobile machinery odometer 
reading an accumulated service of more than d (km) in accordance with Table 6 . 
Test results shall be submitted to the approval authority by [Please OJ insert the 
date forty -eight months after the day of entry into force of this Regulation ].  
 Table 6  
Accumulated service  for ISM groups O and P  
Group  Engine swept  
volume (cm3) c (km)  d (km)  
O Any 1 600  4 400  
P < 100  1 350  5 400  
≥ 100  2 700  10 800  
 
(8) The following points 2.6.5 and 2.6.6 are inserted after point  2.6.4.1.2 : 
2.6.5. The manufacturer may conduct and report more tests than those established by the 
testing schemes set out in points 2. 6.1, 2. 6.2, 2. 6.3 and 2. 6.4.  
2.6.6.  Multiple testing of the same engine to provide data for the consecutive service 
accumulation stages in accordance with points 2. 6.1, 2. 6.2, 2. 6.3 and 2. 6.4 is 
recommended but not mandatory. ’; 
(9) point 3.4.2 is replaced by the following : 
‘3.4.2.  To demonstrate compliance with po int 3.4, samples shall be taken and retained 
until at least , whichever is the shorte st period  of time form the following : EN 10  EN (a) 12 months following the completion of the test, or  
(b) 1 month after the manufacturer submits the respective test report to the 
approval authority .’ 
(10) the following point 3.6. is inserted after point 3 .5: 
‘3.6. Where testing is undertaken outside the Union, the manufacturer must provide evidence 
to the approval authority that the  following conditions  are representative of the test 
conditions to which the non -road mobile machinery would be subject if tested in the 
Union : 
(a) non-road mobile machinery’s operation ; 
(b) ambient conditions ; 
(c) lubricating oil, fuel and reagent ; and 
(d) operating conditions .’; 
(11) point 4.1.1 is deleted.  
(12) point 4.2.2 is replaced by the following:  
‘4.2.2.  The following additional requirements shall be fulfilled when applying combined 
data sampling:  
(a)  the different operating sequences shall be obtained using  the same non -road 
mobile machinery and engine;  
(b) the combined data sampling of tests performed at ambient temperature above 
273,15 K shall contain a maximum of three operating sequences ; 
(c) the combined data sampling of tests performed at ambient temperature equal or 
below  273,15 K shall contain a maximum of six  operating sequences ; 
(d)  the maximum period elapsed between the first and last operating sequence 
shall be 72 hours;  
(e)  combined data sampling shall not be used if an engine malfunction occurs, as 
set out i n point 8 of Appendix 2;  
(f) to be eligible for combined data sampling  each operating sequence of an in -
service monitoring test shall contain the following minimum amount of work 
(kWh) or CO 2 mass (g/cycle):  
(i)  for engines in ISM Groups A and C, a minimum of  one hot -start NRTC 
reference work or CO 2 reference mass;  
(ii) for engines in ISM Group H, a minimum of one LSI -NRTC reference 
work or CO 2 reference mass;  
(iii) for engines in all other ISM Groups, a minimum of one steady -state cycle 
reference work or CO 2 reference mass determined using the method set out 
in Appendix 9.  
In case of an in -service test of an engine type within an engine family , the 
reference value shall be that for the parent engine type;  
(g) prior to joining the operating sequences , all necessary pre -processing shall be 
completed individually for each sequence in accordance with  the requirements 
set out in point 6.3;   EN 11  EN (h) the operating sequences in the combined data sampling shall be joined in a 
chronological order including all data no t excluded by sub -point (f);  
(i) the combined data sampling shall be considered one ISM test;  
(j) the determination of working events set out in point 6.4 and calculations set out 
in point 8 shall be applied to the complete combined data sampling.’;  
(13) the following  point 4.3 is inserted after point 4.2.2:  
‘4.3 Temporary signal loss  
Parameter recording shall reach a data completeness of not less than 
98%, meaning  that a maximum of 2  % of data with no consecutive period of more 
than 30 seconds duration may be excluded  from each operating sequence due to 
one or several episodes of unintended temporary signal loss in the original data 
recording. No signal loss shall be created during pre -processing, combination or 
post-processing of any operating sequence.’;  
(14) Points 5 to 5.2.2 are replaced by the following:  
‘5.  ECU data stream  
5.1. Engines fitted with an ECU and a communication interface shall provide data 
stream information to the measurement instruments or data logger of the PEMS in 
accordance with the requirements set out in Appendix 7.  
5.2. Prior to the in -service test, the availability of the measurement data requested by 
Appendix 7 shall be v alidated . 
(15) Points 5.3 to 5.4 are inserted  after point 5.2:  
5.3. The conformity of the ECU torque signal shall be v alidated  during the in -service 
monitoring in accordance with the method set out in Appendix 6.  
5.4. Where an engine fitted with an ECU and a communication interface does not 
permit fulfilling the requirements set out in points 5.1., 5.2 or 5.3., point 1.4. shall 
apply.’;  
(16) point 6.4 is replaced by the following:  
‘6.4.  Manufacturers shall follow the procedures set out in Appendix 4 for the 
determination of working and non -working events for gaseous pollutant emissions 
calculation following an in -service monitoring te st of engines installed on non -
road mobile machinery using a PEMS.’;  
(17) the following points 6.5 and 6.6 are inserted after point 6.4:  
‘6.5.  In accordance with point 4.2.2, where combined data sampling is used , the 
requirements of points 6.1 to 6.3 shall app ly individually to each operating 
sequence prior to combining operating sequences. The determination of working 
and non -working events set out in point 6.4 and calculations set out in point 8. 
shall be applied to the complete combined data sampling.  
6.6. Figure 3 outlines the complete sequence for conducting in -service monitoring 
including planning, PEMS preparation and installation, test procedures, data pre -
processing, data calculations and validation.  
 
Figure 3  EN 12  EN Illustration of the complete sequence for conducting in -service monitoring  
 
 
 
 
’; 
 
EN 13  EN (18) points 7 and 8 are replaced by the following:  
‘7. Test data availability  
No data shall be modified or removed from the raw test data file(s) used for the 
completion of point 6. Those raw test data file(s) shall be retained at least for 10 
years by the manufacturer and made available upon request to the approval 
authority and the Commission.  
8.  Calculations  
 Manufacturers shall follow the procedures set out in Appendix 5 for the gaseous 
pollutant emissions calculati ons for the in -service monitoring of engines installed on 
on-non-road mobile machinery using a PEMS.  
8.1. In the case of engines with an ECU that were produced with a communication 
interface intended to permit the collection of the engine torque and speed data as 
specified in Table 1 of Appendix 7 , the calculations shall be conducted and results 
reported for both the work -based method and the CO 2 mass -based method. In all other 
cases, the calculations shall be conducted and results reported for the CO 2 mass  based 
method  only. 
8.2. In all cases, the calculations shall be conducted twice following the pre -processing of 
data in accordance with  point 6.3 of this Annex:  
(a) firstly, using only working events determined in accordance with  point 6.4 of 
this Annex and v alid windows, and;  
(b) secondly, using all data not excluded by point 6.3 of this Annex, without 
applying point 6.4 of this Annex, and without exclusion of invalid windows as 
set out in points 2.2.2 and 2.3.1 of Appendix 5. ’; 
(19) Appendix 1 is amended as follows:  
(a) in point 1, point (b) is replaced by the following:  
‘ 
(b) an Exhaust Flow Meter (EFM) based on the averaging Pitot or equivalent 
principle, except where indirect exhaust flow measurement may be applied as 
permitted by note (3) to the table in point 1 of Appendix 2; ’; 
(b) points 2 to 2.2.2 are replaced by the following:  
‘2.  Measurement instruments requirements  
2.1.  Measurement Instruments shall meet the requirements on calibration and 
performance checks set out in Section 8.1 of Annex VI to  Commission  Delega ted 
Regulation (EU) 2017/654 * except as set out in points 2.1.1 and 2.1.2. Special 
attention shall be given to perform the following actions:  
(a) the vacuum -side leak verification of the PEMS as set out in Section 8.1.8.7 of 
Annex VI to Delegated Regulation (E U) 2017/654;  
(b) the response and updating -recording verification of the gas analyser as set out 
in Section  8.1.5 of Annex VI to Delegated Regulation (EU) 2017/654.  
2.1.1.  The minimum frequency for gas analy ser linearity verification and NO2 -to-NO 
converter co nversion verification set out in Tables 6.4 and 6.5 of Annex VI to 
Delegated Regulation (EU) 2017/654 may be increased to 3 months.  EN 14  EN 2.1.2  The minimum frequency of EFM performance and calibration checks, and the details 
of those checks, shall be those speci fied by the instrument manufacturer.  
2.2.  Measurement instruments shall meet the specifications set out in Section 9.4 of 
Annex VI to Delegated Regulation (EU) 2017/654.   
________________________________  
*Commission Delegated Regulation (EU) 2017/654 of 1 9 December 2016 
supplementing Regulation (EU) 2016/1628 of the European Parliament and of the 
Council with regard to technical and general requirements relating to emission limits 
and type -approval for internal combustion engines for non -road mobile machin ery 
(OJ L 102, 13.4.2017, p. 1). ’; 
(c) the following points 2.3 and 3 are inserted after point 2.2:  
2.3.  The analytical gases used for calibrating the measurement instruments shall meet the 
requirements set out in Section 9.5.1 of Annex VI to Delegated Regula tion (EU) 
2017/654.’;  
‘3.  Transfer line and sampling probe requirements  
3.1.  The transfer line shall meet the requirements set out in Section  9.3.1.2 of Annex VI 
to Delegated Regulation (EU) 2017/654.  
3.2.  The sampling probe shall meet the requirements set out in Section  9.3.1.1 of Annex 
VI to Delegated Regulation (EU) 2017/654.’;  
(20) Appendix 2 is amended as follows:  
(a) Points 1. to 4.1. are replaced by the following:  
‘1.  Test Parameters  
1.1 The gaseous pollutant  emissions to be measured and recorded during the in -service 
monitoring test are carbon monoxide (CO), total hydrocarbons (HC) and nitrogen 
oxides (NO x). Additionally, carbon dioxide (CO 2) shall be measured to enable the 
calculation procedures described in  Appendix 5.  
1.2. Where the manufacturer demonstrates to the approval authority that it is not practical 
to combine the flow from multiple exhaust stacks, and there is similarity in the 
technical configuration and operation of the part of the engine exhausting into each 
stack, it shall be sufficient to measure the emissions and exhaust mass flow from one 
exhaust stack. In th at case, when performing the calculations set out in Appendix 5 
the instantaneous mass flow rate of emissions from the measured s tack shall be 
multiplied by the total number of stacks to obtain the total instantaneous mass flow 
rate of emissions for the engine.  
1.3 The parameters set out in the Table shall be measured and recorded at a data 
sampling period of 1 second or less during  the in -service monitoring test:  
Table  
Test parameters  
 
Parameter  Unit (1) Source  
HC concentration (2) ppm Gas analyser  
CO concentration (2) ppm Gas analyser  EN 15  EN NOx concentration (2) ppm Gas analyser  
CO 2 concentration (2) ppm Gas analyser  
Exhaust mass flow (3) kg/h EFM  
Exhaust temperature (4) K EFM or ECU or Sensor  
Ambient temperature (5) K Sensor  
Ambient pressure  kPa Sensor  
Relative humidity  % Sensor  
Engine torque (6) (7) Nm ECU or Sensor  
Engine speed (7) rpm ECU or Sensor  
Engine fuel flow (7) g/s ECU or Sensor  
Engine coolant temperature (8) K ECU or Sensor  
Engine intake air temperature  K ECU or Sensor  
Non-road mobile machinery latitude  degree  GPS (optional)  
Non-road mobile machinery longitude  degree  GPS (optional)  
(1) Where the available data stream uses different units to those required by the table, that data stream shall be transformed 
into the required units during the data pre -processing set out in Appendix 3.  
(2) Measured or corrected to a wet basis.  
(3) Direct measurement of exhaust mass flow shall be used unless one of the following is applicable:  
(a)  the exhaust system installed in the non -road mobile machinery results in dilution of the exhaust by air upstream of the 
location where an EFM could be installed.  In th at case the exhaust sample shall be taken upstream of the point of 
dilution; or,  
(b)  the exhaust system installed in the non -road mobile machinery diverts a portion of the exhaust to another part of the 
non-road mobile machinery (e.g. for heating) u pstream of the location where an EFM could be installed.  
(c) the engine to be tested is of a reference power greater than 560 kW or is installed in an inland waterway vessel or a 
railway vehicle and the manufacturer demonstrates to the approval authority that installation of an EFM is impractical 
due to either the size or location of the exhaust on the NRMM ;   
(d) engines of category SMB and the manufacturer demonstrates to the approval authority that installation of an EFM is 
impractical due to location o f the exhaust on the NRMM.   
 In th ose cases, where the manufacturer is able to provide robust evidence to the approval authority of the correlation 
between the fuel mass flow estimated by the ECU and the fuel mass flow measured on the engine dynamometer t est 
bench, the EFM may be omitted and indirect exhaust flow measurements (from fuel and intake air flows or fuel flow and 
carbon balance) may be applied.  
(4) In order to determine the duration of the take -off phase after a long non -working event for an eng ine equipped with an 
after-treatment device used for NOx reduction, as set out in point 2.2.2 of Appendix 4, the exhaust gas temperature shall 
be measured during the operating sequence within 30 cm of the outlet of the after -treatment device used for NOx 
reduction. Where installing a sensor within 30 cm would result in damage to the after -treatment the sensor shall be 
installed as close to this location as can be practically achieved.  
(5) Use the ambient temperature sensor or an intake air temperature senso r. Use of an intake air temperature sensor shall 
comply with the requirements set out in the second paragraph of point 5.1.  
(6) The recorded value shall be either (a) the net torque; or (b) the net torque calculated from the actual engine percent 
torque, t he friction torque and the reference torque, in accordance with  standards set out in point 2.1.1 of Appendix 7. 
The basis for the net torque shall be uncorrected net torque delivered by the engine inclusive of the equipment and 
auxiliaries to be included f or an emissions test in accordance with Appendix 2 of Annex VI to Delegated Regulation (EU) 
2017/654.  
(7) Not required for engines tested under this Regulation that are not designed to have a communication interface capable to 
provide these data streams.  EN 16  EN (8)  In the case of air -cooled engines, the temperature at the reference point location identified in point 3.7.2.2.1 of PART C 
of Appendix 3 of Annex I to Implementing Regulation (EU) 2017/656 shall be recorded in place of the coolant 
temperature.   
2.  Test duration  
2.1. The test duration, comprising all operating sequences, shall be long enough to obtain 
the following amount of working events:  
(a) for engines in ISM groups A and C, between five and seven times the reference 
work in kWh performed on the hot -start NRTC run during the type -approval 
test or to produce between five and seven times the CO 2 reference mass in 
g/cycle from the hot -start NRTC run of the type -approval test as specified in 
points 11.3.1 . and 11.3.2 . of the addendum to the EU type approval certificate 
of the engine type or the engine family set out in Annex IV to Implementing 
Regulation (EU) 2017/656;  
(b) for engines in ISM group H, between five and seven times the reference work 
in kWh performed on the L SI-NRTC during the type -approval test or to 
produce between five and seven times the CO 2 reference mass in g/cycle of the 
LSI-NRTC during the type -approval test as specified in points 11.3.1 and 
11.3.2 of the addendum to the EU type approval certificate of  the engine type 
or the engine family set out in Annex IV to Implementing Regulation (EU) 
2017/656;  
(c) for engines in ISM groups E, I, O and P between three and five times the 
applicable reference work in kWh or CO 2 reference mass in g/cycle determined 
from t he type -approval test result using the method set out in Appendix 9 ; 
(d) for engines in ISM groups not listed in sub -points (a), (b) or (c), between five 
and seven times the applicable reference work in kWh or CO 2 reference mass 
in g/cycle determined from the type-approval test result using the method set 
out in Appendix 9.  
2.2. All data collected during all operating sequences shall be assembled chronologically 
even if the maximum amount of work or CO 2 mass specified in point 2.1 , sub -points  
(a) to (d) is exce eded.  In that case, during the calculation set -out in Appendix 5 of 
this Regulation:  
(a)  when the amount of work or CO 2 reference mass in the working events 
exceeds that maximum, the calculation shall be truncated at the end of the time 
increment in which th at occurs; and,  
(b) the results reported for the ISM test in accordance with  point 10 of th is Annex 
to this Regulation shall be those of that truncated calculation.  
3. Preparation of the non -road mobile machinery  
The preparation of the non -road mobile machinery whose engine has been selected 
for testing in accordance with point 1.3 of th is Annex shall comprise of at least the 
following:  
(a)  the check of the engine: any identified problems, once solved, shall be 
recorded and presented to the approval author ity; 
(b)  the replacement of the oil, fuel and reagent, if any, where no documented 
evidence is available that the fluid in question complies with the specification EN 17  EN listed in the type -approval information package applicable to the engine type, 
and it is practi cally and economically feasible to do so;  
(c) engines fitted with an ECU and a communication interface shall comply with 
point 5 of th is Annex.  
4. Installation of the PEMS  
4.1 Installation constraints  
4.1.1.  The installation of the PEMS shall not influence the  non-road mobile machinery 
gaseous pollutant emissions or performance.  
4.1.2.  The installation shall comply with the locally applicable safety regulations and 
insurance requirements and shall follow the instructions issued by the PEMS, 
measurement instrum ents, transfer line and sampling probe manufacturer.  
4.1.3.  Where for engines of ISM groups M and N it is not possible to install the PEMS 
systems without exceeding the loading gauge applicable to the rail network, the use 
of point 3.2.2 of th is Annex shal l include testing of the railway vehicle whilst 
stationary using a representative test duty cycle determined by the manufacturer and 
agreed with the approval authority.  
4.1.4.  For engines of ISM groups E, I, O and P the engine may be removed from the non -
road mobile machinery and the in -service monitoring test conducted on a 
dynamometer test bench. In that case , the following shall apply:  
(a) the engine inclusive of the entire emission control system shall be removed 
from the non -road mobile machinery and insta lled on the dynamometer test 
bench without adjustment to the emission control system;  
(b) it shall not be necessary to demonstrate to the Approval Authority that it is not 
possible to comply with point 3.2.1 of th is Annex;  
(c) notwithstanding sub -points (a) and (b ), the in -service monitoring test shall be 
conducted in accordance with this Regulation;  
(d) the procedure for removing engine from non -road mobile machinery and 
installing in test cell to replicate operation in the non -road mobile machinery 
shall be agreed wi th the approval authority prior to conducting the ISM test;  
(e) a representative test duty cycle shall be used as determined by the manufacturer 
and agreed with the approval authority in accordance with  point 3.2.2 of th is 
Annex;  
(f) the test duty cycle of sub -point (e) shall span a range of speed and load that 
represents the operation of the selected machine when used in the field.  
Methods to establish that range shall include, but are not limited to, logging 
operational data for one or more comparable machines o perated in the field;  
(g) to establish data on the extent to which results obtained from use of a PEMS 
system differ from those obtained from the use of a test bench system, in -
service monitoring measurements performed on the dynamometer test bench 
using the P EMS system may be supplemented by concurrent measurements 
using test bench instrumentation and an emission measurement system 
complying with the requirements of Section 9 of Annex VI to Delegated 
Regulation (EU) 2017/654, operated in accordance with  the requirements of 
section 8 of that Annex;  EN 18  EN (h) the requirements of points 6, 7, 8 and 10 of th is Annex shall additionally apply 
to any concurrent measurements in accordance with  sub-point (g) and the test 
data and test report shall include these measuremen ts.’; 
(b) point 4.6 is replaced by the following:  
‘4.6.  Data logger  
Where ECU data is to be used , a data logger shall be connected with the engine 
ECU to record the available engine parameters listed in Table 1 of Appendix 7, 
and, where applicable, the engin e parameters listed in Table 2 of Appendix 7.’;  
(c) point 5.1 is replaced by the following:  
‘5.1.  Ambient temperature measurement  
The ambient temperature shall at a minimum be measured at the beginning of the 
operating sequence and at the end of the operating sequence. The measurement 
shall be made within a reasonable distance from the non -road mobile machinery. 
A sensor or ECU signa l for engine intake air temperature  may be used.  
If intake air temperature is used to estimate the ambient temperature , the recorded 
ambient temperature shall be the intake air temperature adjusted by the applicable 
nominal offset between ambient and int ake air temperature as specified by the 
manufacturer. ’;  
(d) Points 6 to 8.2 are replaced by the following:  
‘6. In-service monitoring test data logging  
6.1.  Before the operating sequence  
Gaseous pollutant emissions data sampling, measurement of the exhaust 
parameters and recording of the engine and ambient data shall start prior to 
starting the engine.  
6.2.  During the operating sequence  
Gaseous pollutant emissions data sampling, measurement of the exhaust 
parameters and recording of the engine and ambient da ta shall continue 
throughout the normal in -use operation of the engine.  
The engine may be stopped and started, but the gaseous pollutant emissions data 
sampling, measurement of the exhaust parameters , recording of the engine and 
ambient data shall continu e throughout the entire in -service monitoring operating 
sequence.  
6.3.  After the operating sequence  
At the end of the in -service monitoring operating sequence, sufficient time shall 
be given to the measurement instruments and data logger to allow their re sponse 
times to elapse. The engine may be shut down before or after data logging is 
stopped.  
7. Checking of gas analysers  
7.1.  Periodic zero verification during the operating sequence  
Where practical and safe to perform, zero verification of the gas analy sers may be 
conducted every 2 hours during an operating sequence.  
7.2.  Periodic zero correction during the operating sequence  EN 19  EN The results obtained with the checks performed in accordance with point 7.1 may 
be used to perform a zero drift correction during  that operating sequence.  
7.3.  Drift verification after the operating sequence  
The drift verification shall be performed only if no zero drift correction was made 
during the operating sequence in accordance with point 7.2.  
7.3.1.  No later than 30 minutes  after the operating sequence is completed, the gas 
analysers shall be zeroed and spanned in order to verify their drift compared to the 
pre-test results.  
7.3.2.  The zero, span and linearity checks of the gas analysers shall be performed as set 
out in poi nt 5.4.  
8.  Engine or machine malfunction  
8.1.  In the case that a malfunction occurs during an operating sequence that affects 
engine operation and either:  
(a)  the non -road mobile machinery operator is clearly notified of that malfunction 
by the on -board dia gnostics system via a malfunction visual warning, text 
message or other indicator; or,  
(b) the non -road mobile machinery is not fitted with a malfunction diagnostic or 
warning system, but the malfunction is clearly detected by aural or visual 
means;  
the operating sequence shall be considered void.  
8.2.  Any malfunction shall be corrected before any further operating sequence is 
conducted on the engine. ’; 
(21) in Appendix 3 , points 2 to 6 are replaced by the following:  
‘2. Exclusion of data  
2.1. Temporary signal loss  
2.1.1  Any episodes of temporary signal loss shall be identified.  
2.1.2.  A maximum of 2  % of data with no consecutive period more than 30 seconds 
duration may be excluded from each operating sequence due to one or several 
episodes of unintended temporary signal loss in the original data recording, in 
accordance with point 4.3 of the Annex.  
2.1.3.  In the case that the test sequence contains episodes of signal loss either greater 
than 2  % of data or for a consecutive period greater than 30 seconds , that entire 
sequence shall be considered void and a further test shall be run.  
2.2. Periodic checks of measurement instruments  
2.2.1.  Any data points corresponding with checking of gas analysers in accordance with  
point 7 of Appendix 2 shall be identified  and excluded from further processing of 
an operating sequence except as required to perform the drift correction in point 3 
of this Appendix.  
2.3. Ambient conditions  
2.3.1.  Any data points in an operating sequence corresponding with ambient conditions 
that do not comply with the requirements set out in point 3.3 of th is Annex shall 
be identified.  EN 20  EN 2.3.2.  If the proportion of data points identified at Point 2.3.1 of this Appendix exceeds 
1 % that entire sequence shall be considered void and a further test sh all be run.  
2.3.2  In the case that ambient conditions are only measured at the start and the end of 
the test the entire test sequence shall be considered void if either measurement 
does not comply with the requirements set out in point 3.3 of the Annex.  
2.4  Cold start data  
Cold start gaseous pollutant emissions measured data shall be excluded prior to 
the gaseous pollutant emissions calculations.  
2.4.1.  Liquid -cooled engines  
 Valid measured data for gaseous pollutant emissions calculations shall start af ter 
the engine coolant temperature has reached 343 K (70 °C) for the first time or 
after the engine coolant temperature is stabilised within +/ – 2 K over a period of 5 
minutes, whichever comes first; in any case , it shall start no later than 20 minutes 
after starting the engine.  
2.4.2.  Air-cooled engines  
 Valid measured data for gaseous pollutant emissions calculations shall start after 
the temperature measured at the reference point identified in point 3.7.2.2.1 of 
PART C of Appendix 3 of Annex I to Implementing R egulation (EU) 2017/656 is 
stabilised within +/ – 5 % over a period of 5 minutes; in any case , it shall start no 
later than 20 minutes after starting the engine.  
3.  Drift correction  
3.1.  Maximum drift allowed  
Drifts of the zero response and the span response shall be less than 2 % of full 
scale on the lowest range used:  
(a) if the difference between the pre -test and post -test results is less than 2 %, the 
measured concentrations may be used uncorrected or may be corrected for 
driftin accordance w ith point 3.2;  
(b) if the difference between the pre -test and post -test results is equal to or greater 
than 2 %, the measured concentrations shall be drift corrected in accordance 
with point 3.2. If no correction is made, the test shall be considered void.  
3.2.  Drift correction  
3.2.1.  The corrected  drift concentration value shall be calculated in accordance with the 
requirements set out in Section s 2.1 or 3.5 of Annex VII to Delegated Regulation 
(EU) 2017/654.  
3.2.2.  The difference between the uncorrected and the corrected brake -specific gaseous 
pollutant emission values shall be within ± 6 % of the uncorrected brake -specific 
gaseous pollutant emission values. If the drift is greater than 6 %, the test shall be 
conside red void.  
3.2.2.1  Each brake -specific gaseous pollutant emission value shall be calculated from the 
integrated mass of gaseous pollutant emission of the test sequence divided by the 
total work performed during the test sequence. Th at calculation shall be 
performed prior to determination of working events in accordance with  Appendix 
4 or calculation of gaseous pollutant emissions in accordance with  Appendix 5.  EN 21  EN 3.2.3.  If drift correction is applied, only the drift -corrected gaseous pollutant emission 
results shall be used when reporting gaseous pollutant emissions.  
4.  Time alignment  
To minimise the biasing effect of the time lag between the different signals on the 
calculations of the mass of the gaseous pollutant emissions, the data relevant for 
gaseous poll utant emissions calculations shall be time aligned, in accordance with 
the requirements set out in points 4.1 to 4.4.  
4.1.  Gas analysers data  
The data from the gas analysers shall be properly aligned in accordance with the 
requirements set out in Section 8.1.5.3 of Annex VI to Delegated Regulation (EU) 
2017/654.  
4.2.  Gas analysers and EFM data  
The data from the gas analysers shall be properly aligned with the data of the 
EFM using the procedure set out in point 4.4.  
4.3.  PEMS and engine data  
The data fro m the PEMS (gas analysers and EFM) shall be properly aligned with 
the data from the engine ECU using the procedure in point 4.4.  
4.4.  Procedure for improved time alignment of the PEMS data  
The test parameters listed in the Table of Appendix 2 are split i nto three different 
categories:  
Category 1: Gas analysers (HC, CO, CO 2, NO x concentrations);  
Category 2: EFM (Exhaust mass flow and exhaust temperature);  
Category 3: Engine (Torque, speed, temperatures, fuel rate from ECU).  
The time alignment of each c ategory with the other two categories shall be 
verified by finding the highest correlation coefficient between two series of test 
parameters. All the test parameters in a category shall be shifted to maximise the 
correlation factor. The following test para meters shall be used to calculate the 
correlation coefficients:  
(a) Categories 1 and 2 (Gas analysers and EFM data) with Category 3 (Engine 
data): the exhaust mass flow from the EFM with torque from the ECU;  
(b) Category 1 with Category 2: the CO 2 concentration and the exhaust mass flow;  
(c) Category 1 with Category 3: the CO 2 concentration and the engine fuel flow.   
4.4.1  In the case of engines not designed to have a communication interface to permit 
the collection of the ECU data as specified in Ap pendix 7 the correlation at  point 
4.4, sub-points (a) and (c) shall be omitted.  
4.4.2  In the case of engines for which direct measurement of exhaust mass flow was 
omitted in accordance with  note (3) to the Table of Appendix 2 the correlation at 
point 4.4, sub-point (a) shall be omitted.  
5.  Data consistency check  
5.1. Gas analysers and EFM data  EN 22  EN For engines designed to have a communication interface capable to provide fuel 
flow in accordance with  Table 2 of Appendix 7 the consistency of the data 
(exhaust mas s flow measured by the EFM and gas concentrations) shall be 
verified using a correlation between the measured engine fuel flow from the ECU 
and the engine fuel flow calculated in accordance with the procedure set out in 
Section 2.1.6.4 of Annex VII to Dele gated Regulation (EU) 2017/654.  
A linear regression shall be performed for the measured and calculated fuel rate 
values. The method of least squares shall be used, with the best fit equation 
having the form:  
y = mx + b  
Where:  
– (a) y is the calculated fuel f low [g/s];  
– (b) m  is the slope of the regression line;  
– (c) x is the measured fuel flow [g/s];  
– (d) b  is the y intercept of the regression line.  
 
The slope (m) and the coefficient of determination ( R2) shall be calculated for 
each regression line. It is recommended to perform this analysis in the range from 
15 % of the maximum value to the maximum value and at a frequency greater or 
equal to 1 Hz. For a test to be considered valid, the following two cr iteria shall be 
evaluated:  
Table  1 
Tolerances  
Slope of the regression line, m  0,9 to 1,1 - Recommended  
Coefficient of determination, r2 Min. 0,90 - Mandatory  
 
5.2.  ECU torque data  
Where ECU torque data is to be used in the calculations the consistency of the 
ECU torque data shall be verified by comparing the maximum ECU torque values 
at different (if appropriate) engine speeds with the corresponding values on the 
official engine full load torque curve and in accordance with Appendix 6.  
5.3.  Brake -Specific Fuel Consumption (BSFC)  
Where ECU data is available the BSFC shall be checked using:  
(a) the fuel consumption calculated from the gaseous pollutant emissions data (gas 
analysers concentrations and exhaust mass flow data), in accordance with the 
procedure set out in Section 2.1.6.4 of Annex VII to Delegated Regulation 
(EU) 2017/654;  
(b) the work calculated using the data from the ECU (Engine torque and engine 
speed).  
5.4.  Ambient pressure  EN 23  EN The ambient pressure value shall be checked against the altitu de indicated by the 
GPS data, if available.  
5.5.  The approval authority may consider the test void if it is not satisfied with the 
results of the data consistency check.  
6.  Dry-wet correction  
If the concentration is measured on a dry basis, it shall be c onverted to a wet basis 
in accordance with the procedure set out in Section 2 or 3 of Annex VII to 
Delegated Regulation (EU) 2017/654.  
7. NOx correction for humidity and temperature  
The NOx concentrations measured by the gas analysers shall not be correcte d for 
ambient air temperature and humidity. ’; 
(22) in Appendix 4, points 2. and 3. are replaced by the following:  
‘2.  Procedure to determine non -working events  
2.1.  Non-working events are those where either:  
(a) for engines not designed to have a communication in terface capable to provide 
torque and speed data in accordance with  Table 1 of Appendix 7, the 
instantaneous proxy power determined in accordance with  the procedure set -
out in Appendix 10, or;  
(b) in all other cases, the instantaneous engine power,  
is below 10  % of the engine reference power, as defined in Article 3 , point (26) of 
Regulation (EU) 2016/1628 and listed in Annex I to that Regulation for each 
engine (sub -)category, for the engine type subject to ISM test.   
2.1.1  For engines tested under this Regu lation that are not designed to have a 
communication interface capable to provide torque and speed data in accordance 
with Table 1 of Appendix 7 the instantaneous proxy power shall be calculated 
using the procedure described in Appendix 10 prior to applyin g the procedure in 
this Appendix.  
2.2.  The following additional steps shall be conducted:  
2.2.1.  Non-working events shorter than D0 shall be considered as working events and 
merged with the surrounding working events (see Table  2 for the values of D0).  
2.2.2.  Working events shorter than D0 surrounded by non -working events of duration 
longer than D1 shall be considered non -working events and merged with the 
surrounding non -working events (see Table  2 for the values of D1)  
2.2.3.  The take -off phase follow ing long non -working events (> D2) for engines 
equipped with an after -treatment device used for NOx reduction and exhaust gas 
temperature measurement in accordance with  note (4) to the Table of Appendix 2 
shall also be considered as a non -working event unt il the exhaust gas temperature 
reaches 523 K. If the exhaust gas temperature does not reach 523 K within D3 
minutes, all events after D3 shall be considered as working events (see Table  2 
for the values of D2 and D3).  
2.2.4.  For all non -working events, the first D1 minutes of the event shall be considered 
as working event.  
3.  ‘Machine work’ marking algorithm to implement the requirements of point 2  EN 24  EN  Point 2 shall be implemented in the sequence set out in points 3.1 to 3.4  
3.1.  Step 1: Detect and split into working events and non -working events.  
(a) identify the working events and non -working events in accordance with point 
2.1;  
(b) calculate the duration of non -working events;  
(c) mark the non -working events shorter than D0 as working events;  
(d) calculate the durat ion of the working events.  
3.2.  Step 2: Merge short working events (≤ D0) into non -working events.  
 Mark as non -working events those working events shorter than D0 that are both 
preceded and followed by remaining non -working events of duration longer th an 
D1. 
3.3.  Step 3: Exclude working events after long non -working events (take -off phase).  
 Where point 2.2.3 is applicable, mark as non -working events those working 
events after long non -working events  (> D2)  until either;  
(a) the exhaust gas temperature re aches 523 K; or  
(b)  D3 minutes have elapsed;  
whatever happens first.  
3.4.  Step 4: Include non -working events after working events.  
 Include D1 minutes of non -working event following any working event as part of 
that working event.  
Table  2 
Values for the parameters D0, D1, D2 and D3  
Parameters  Value  
D0 2 minutes  
D1 2 minutes  
D2 10 minutes  
D3 4 minutes  
’; 
(23) In Appendix 5, points 2.1 to 2.3.2 are replaced by the following:  
‘2.1.  Averaging window method  
2.1.1.  General requirements  
Averaging window is the sub-set of the complete calculated data set during the in -
service monitoring test whose work or CO 2 mass is equal to the engine work or 
CO 2 mass measured over the reference laboratory test cycle.The mass of the 
gaseous pollutant emissions and the conformit y factors shall be calculated using 
the moving averaging window method, based on the reference work (procedure EN 25  EN set out point 2.2) and the reference CO 2 mass (procedure set out in point 2.3) 
measured over the reference laboratory test cycle.  
The engine powe r versus time and averaging window gaseous pollutant emissions, 
starting f rom the first averaging window.  
The calculations shall be conducted in accordance with the following sub -points:  
(a) any data excluded, under the terms of Appendix 4, shall not be consid ered for 
the calculations of the work or CO 2 mass and the gaseous pollutant emissions 
and conformity factors of the averaging windows, except as required by point 
4(f) of this Appendix;  
(b) the moving averaging window calculations shall be conducted with a tim e 
increment Δt equal to the data sampling period. The start of the moving 
average window shall be incremented by that amount at each iteration;  
(c) the mass of the gaseous pollutant emissions for each averaging window 
(mg/averaging window) shall be obtained by  integrating the mass of the 
instantaneous gaseous pollutant emissions  in the averaging window;   
(d) in the case of engines with an ECU that were designed with a communication 
interface intended to permit the collection of the engine torque and speed data 
as specified in Table 1 of Appendix 7 , the calculations shall be conducted and 
results reported for both the work based method and the CO 2 mass -based 
method. In all other cases the calculations shall be performed, and results 
reported, for only the CO 2 mass -based method.  
Figure 4 
Engine power versus time and averaging window gaseous pollutant emissions, starting from 
the first averaging window, versus time  
 
 
EN 26  EN  
 
2.1.2.  Reference values  
The reference work and reference CO 2 mass of an engine type, or for all engine 
types within the same engine family, shall be determined as follows:  
(a) for engines in ISM groups A and C those values from the hot -start NRTC run 
of the type -approval test of the parent engine as specified in points  11.3.1 and 
11.3.2 of the addendum to the EU type approval certificate of the engine type 
or the engine family, as set out in Annex IV to Implementing Regulation (EU) 
2017/656;  
(b) for engines in ISM group H those values from the LSI -NRTC run of the type -
appro val test of the parent engine;  
(c) for engines in ISM groups not listed in sub -points (a) or (b) those values 
determined from the type -approval test result of the parent engine using the 
method set out in Appendix 9.  
 
2.2  Work based method  
Figure 5 
Work -based  method  
EN 27  EN  
The duration ( t 2,i – t 1,i ) of the ith averaging window is determined by:  
W(t 2,i ) – W(t 1,i ) ≥ Wref 
Where:  
– W(t j,i ) is the engine work measured between the start and time t j,i , kWh,  
– Wref is the engine reference work determined according to point 2.1.2, kWh,  
– t 2,i shall be selected such that:  
W(t 2,i – Δt) – W(t 1,i ) < W ref ≤ W(t 2,i ) – W(t 1,i ) 
Where Δt is the data sampling period, equal to 1 second or less.   
2.2.1.  Calculations of the brake specific gaseous pollutant emissions  
The brake -specific gaseous pollutant emissions egas (g/kWh) shall be calculated 
for each averaging window and each gaseous pollutant in the following way:  
𝑒𝑔𝑎𝑠=𝑚𝑖
𝑊(𝑡2,𝑖) – 𝑊(𝑡1,𝑖) 
Where:  
– mi is the mass emission of the gaseous pollutant during the ith averaging 
window, g/averaging window,  
– W(t 2,i ) – W(t 1,i ) is the engine work during the ith averaging window, kWh.  
2.2.2.  Selection of valid averaging windows  
The valid averaging windows are the averaging windows whose average power 
exceeds the power threshold of 20 % of the reference power, as defined in Article 
3, point (26), of Regulation (EU) 2016/1628 and listed in Annex I to that 
EN 28  EN Regulation for each engine (sub -)category, for  the engine type subject to ISM test, 
except for engines of category ATS where the reference power is the power at 
intermediate speed as defined in Section  5.2.5.4 , point (f) of Annex VI to 
Delegated Regulation  (EU) 2017/654. The percentage of valid averag ing windows 
shall be equal or greater than 50 %.  
2.2.2.1.  If the percentage of valid windows is less than 50 %, the data evaluation shall be 
repeated using lower power thresholds. The power threshold shall be reduced 
from 20  % in steps of 1 % until the p ercentage of valid windows is equal to or 
greater than 50 %.   
2.2.2.2.  In any case, the lower power threshold shall not be lower than 1 0 %. 
2.2.2.3.  The test shall be considered void if the percentage of valid averaging windows is 
less than 50 % at a power  threshold of 1 0 %. 
2.2.3.  Calculations of the conformity factors  
The conformity factors shall be calculated for each individual valid averaging 
window and each individual gaseous pollutant in the following way:  
𝐶𝐹=𝑒𝑔𝑎𝑠
𝐿 
Where:  
–  egas is the brake -specific emission of the gaseous pollutant, g/kWh;  
–  L is the applicable limit, g/kWh.  
2.3.  CO 2 mass -based method  
Figure 6 
CO 2 mass -based method  
 
 
EN 29  EN The duration ( t 2,i – t 1,i ) of the ith averaging window is determined by:  
𝑚𝐶𝑂2(𝑡2,𝑖)−𝑚𝐶𝑂2(𝑡1,𝑖)≥𝑚𝐶𝑂2,𝑟𝑒𝑓 
Where:   
– 𝑚𝐶𝑂2(𝑡1,𝑖) is the CO 2 mass measured between the test start and time t j,i , g;  
– 𝑚𝐶𝑂2,𝑟𝑒𝑓 is the reference CO 2 mass determined in Grams (g) in accordance 
with point 2.1.2,  
– —   t 2,i shall be selected such as:  
𝑚𝐶𝑂2(𝑡2,𝑖−∆𝑡)−𝑚𝐶𝑂2(𝑡1,𝑖)<𝑚𝐶𝑂2,𝑟𝑒𝑓≤𝑚𝐶𝑂2(𝑡2,𝑖)−𝑚𝐶𝑂2(𝑡1,𝑖) 
Where Δt is the data sampling period, equal to 1 second or less.  
The CO 2 masses are calculated in the averaging windows by integrating the 
instantaneous gaseous pollutant emissions c alculated in accordance with  the 
requirements introduced in point 1.  
2.3.1.  Selection of valid averaging windows  
The valid averaging windows shall be those whose duration does not exceed the 
maximum duration calculated from:  
𝐷𝑚𝑎𝑥 =3 600 ∙𝑊𝑟𝑒𝑓
0,2∙𝑃𝑚𝑎𝑥 
Where:  
— Dmax is the maximum averaging window duration, s,   
— Pmax is the reference power, as defined in Article 3 , point (26), of Regulation (EU) 
2016/1628, kW, and listed in Annex I to that Regulation for each engine (sub -
)category, for the engine type subject to ISM test, except for engines of category 
ATS where the reference power is the power at intermediate speed as defined in 
Section  5.2.5.4. , point (f), of Annex VI to  Delegated  Regulation  (EU) 2017/654.  
The percentage of valid averaging windows shall be equal or greater than 50 %. 
2.3.1.1.  If the percentage of valid windows is less than 50 %, the data evaluation shall be 
repeated using longer window durations. This is achieved by decreasing the value 
of 0,2 in the formula given in point 2.3.1 by steps of 0,01 until the percentage of 
valid windows is equal to or greater than 50 %.  
2.3.1.2.  In any case, the lowest value in the above formula shall not be lower than 0,1 0. 
2.3.1.3.  The test shall be void if the percentage of valid windows is less than 50 % at a 
maximum window duration calculated in accordance with points 2.3.1., 2.3.1.1 . 
and 2.3.1.2 . 
2.3.2.  Calculations of the conformity factors  
The conformity factors shall be calc ulated for each individual averaging window 
and each individual pollutant in the following way:  
𝐶𝐹=𝐶𝐹𝐼
𝐶𝐹𝐶 
With  EN 30  EN 𝐶𝐹𝐼=𝑚𝑖
𝑚𝐶𝑂2(𝑡2,𝑖)−𝑚𝐶𝑂2(𝑡1,𝑖)  (in service ratio) and  
𝐶𝐹𝐶=𝑚𝐿
𝑚𝐶𝑂2,𝑟𝑒𝑓  (certification ratio)  
Where:  
— mi is the mass  emission of the gaseous pollutant during the ith averaging window, 
g/averaging window,  
— 𝑚𝐶𝑂2(𝑡2,𝑖)−𝑚𝐶𝑂2(𝑡1,𝑖) is the CO 2 mass during the ith averaging window, 
g/averaging window,  
—𝑚𝐶𝑂2,𝑟𝑒𝑓 is the reference engine CO 2 mass determined in acco rdance with  point 
2.1.2,  sub-point  (g),  
— mL is the mass emission of gaseous pollutant corresponding to the applicable limit 
on the reference test cycle, g.  
mL is determined as follows:  
𝑚𝐿=𝐿∙𝑊𝑟𝑒𝑓 
Where:  
— L is the applicable limit, g/kWh  
— Wref is the engine reference work determined in accordance with  point 2.1.2, 
kWh. ’; 
(24) In Appendix 6, point 2 , is replaced by the following:  
‘2. Impossibility to check the conformity of the ECU torque signal  
 When the manufacturer demonstrates to the approval authority that it is not 
possible to check the ECU torque signal during the in -service monitoring test, the 
verification performed in accordance with  the requirements of Appendix 3 of 
Annex VI to Delegated  Regulation (EU) 2017/654 during the tests required for 
EU type - approval and stated in the EU type -approval certificate shall be accepted 
by the approval authority.  
For engines in ISM groups other than A, C and H , the approval authority may 
accept a separ ate demonstration conducted in accordance with  the requirements of 
Appendix 3 of Annex VI to  Delegated  Regulation (EU) 2017/654 but using the 
following mapping procedures of that Annex:  
(a) for engines in ISM group I, and variable speed engines in ISM groups E , F, G, 
J, K, L, M and N, Section  7.6.1;  
(b) for all other engines, Section  7.6.3.  
Where mapping is performed at constant speed in accordance with  sub-point (b) , 
it shall be sufficient to measure and compare the readings of the torque measured 
by the dynamomet er and the torque broadcast by the ECU at the single point of 
rated net power. ’; 
(25) In Appendix 7 , points 1 to 1.3 are replaced by the following:  
‘1. Data to be provided  
1.1 Where an ECU is used to provide engine torque, speed or coolant temperature that 
data at a minimum shall be provided in accordance with Table 1.  EN 31  EN Table 1  
Measurement data  
Parameter  Unit (1) 
Engine torque (2) Nm 
Engine speed  rpm 
Engine coolant temperature  K 
(1) Where the available data stream uses different units to those required by the  table, that data 
stream shall be transformed into the required units during the data pre -processing set out in 
Appendix 3.  
(2) The provided value shall be either (a) the net brake engine torque or (b) the net brake engine 
torque calculated from other appropriate torque values as defined in the corresponding protocol 
standard set out in point 2.1.1. The basis for the net torque shall be uncorrected net torque 
delivered by the engine inclusive of the equipment and auxiliaries to be included for an 
emissi ons test in accordance with Appendix 2 of Annex VI to Delegated Regulation (EU) 
2017/654.  
1.2. Where either ambient pressure or ambient temperature are not measured by 
external sensors, they shall be provided by the ECU in accordance with  Table 2.  
Table 2  
Additional measurement data  
Parameter  Unit (1) 
Ambient temperature (2) K 
Ambient pressure  kPa 
Engine fuel flow  g/s 
(1) Where the available data stream uses different units to those required by the table, that data stream 
shall be transformed into the required units during the data pre -processing set out in Appendix 3.  
(2) Use of an intake air temperature sensor shall comply with the requirements set out in the second 
paragraph of point 5.1 of Appendix 2.  
1.3. Where exhaust mass flow is not measured directly, the engine fuel flow shall be 
provided in accordance with  the Table of Appendix 2 ’; 
(26) Appendix 8 is amended as follows:  
(a) data entries  2 to 2.20 are  replaced by the following:  
‘2.  Engine information  
2.1.  ISM Group  
2.2.  Category and sub -category of the engine type/engine family  
2.3.  Type approval number  
2.4.  Commercial name(s) (if applicable)  
2.5 Engine family designation (if member of a family)  
2.6 Reference work [kWh]  EN 32  EN 2.7 Reference CO 2 mass [g]  
2.8 Engine type designation  
2.9.  Engine identification number  
2.10.  Engine production year and month  
2.11.  Engine rebuilt (yes/no)  
2.12.  Engine total swept volume [cm3]  
2.13.  Number of cylinders  
2.14.  Engine declared rated net power/rated speed [kW/rp m]  
2.15.  Engine maximum net power/power speed [kW/rpm]  
2.16.  Engine declared maximum torque/torque speed [kW/rpm]  
2.17.  Idle speed [rpm]  
2.18.  Manufacturer supplied full -load torque curve available (yes/no)  
2.19.  Manufacturer supplied full -load t orque curve reference number  
2.20.  Installed DeNO x system (e.g. , EGR, SCR)  
2.21.  Installed type of catalytic converter  
2.22.  Installed type of particulate after -treatment  
2.23.  After -treatment modified with respect to type approval (yes/no)  
2.24.  Installed ECU information (Software calibration number)’;  
(b) data entries 9 to 9.11 are  replaced by the following:  
‘9. Averaging window (1) conformity factors (determined in accordance with 
Appendices 3 to 5)  
 (Minimum, maximum and 90th cumulative percentile)   
9.1. Work averaging window THC conformity factor [ -] (2) 
9.2. Work averaging window CO conformity factor [ -]  
9.3. Work averaging window NOx conformity factor [ -] (3) 
9.4. Work averaging window THC + NOx conformity factor [ -] (4) 
9.5. CO 2 mass averaging window THC conformity factor [ -] (5) 
9.6. CO 2 mass averaging window CO conformity factor [ -]  
                                                 
1 Averaging window is the sub -set of the complete calculated data set during the in -service monitoring test whose 
CO 2 mass or work is equal to the engine reference CO 2 mass or work measured over the applicable parent engine 
reference laboratory NRTC or NRSC   
2 Only applicable for engine (sub -)categories which have separate limits for HC and NOx in accordance with  [Please 
make change to all similar footnotes ] Annex II of  Regulation (EU) 2016/1628.  
3 Only applicable for engine (sub -)categories which have separate limits for HC and NOx according to Annex II of 
Regulation (EU) 2016/1628.  
4 Only applicable for engine (sub -)categories which have a combined emission limit for  HC + NOx according to 
Annex II of Regulation (EU) 2016/1628.  
5 Only applicable for engine (sub -)categories which have separate limits for HC and NOx according to Annex II of 
Regulation (EU) 2016/1628.  EN 33  EN 9.7. CO 2 mass averaging window NOx conformity factor [ -] (6) 
9.8. CO 2 mass averaging window THC+NOx conformity factor [ -] (7) 
9.9. Work averaging window: minimum and maximum averaging window power [%]  
9.10.  CO 2 mass averaging window: minimum and maximum averaging window duration 
[s]  
9.11.  Work averaging window: percentage of valid averaging windows  
9.12  CO 2 mass averaging window: percentage of v alid averaging windows ’; 
(c) data entries 10  to 10.8 are replaced by the following:  
‘10. Averaging window conformity factors (determined in accordance with Appendices 3 
and 5 without the determination of working and non -working events in accordance 
with Append ix 4 and without the exclusion of invalid windows as set out in points 
2.2.2 and 2.3.1 of Appendix 5)  
 (Minimum, maximum and 90th cumulative percentile)  
10.1.  Work averaging window THC conformity factor [ -] (8) 
10.2.  Work averaging window CO conformity fa ctor [ -]  
10.3.  Work averaging window NO x conformity factor [ -] (9) 
10.4.  Work averaging window THC+NO x conformity factor [ -] (10) 
10.5.  CO 2 mass averaging window THC conformity factor [ -] (11) 
10.6.  CO 2 mass averaging window CO conformity factor [ -]  
10.7.  CO 2 mass averaging window NO x conformity factor [ -] (12) 
10.8.  CO 2 mass averaging window THC+NO x conformity factor [ -] (13) 
10.9.  Work averaging window: minimum and maximum averaging window power [%]  
10.10.  CO 2 mass averaging window: minimum and maximum ave raging window duration 
[s]’; 
(d) data entries I -2 to I -2.20. are replaced by the following:  
I-2. Instantaneous calculated data  
I-2.1. THC mass [g/s]  
                                                 
6 Only applicable for engine (sub -)categories which have separate limits for HC and NOx according to Annex II of 
Regulation (EU) 2016/1628.  
7 Only applicable for engine (sub -)categories which have a combined emission limit for HC + NOx according to 
Annex II of Regulation (EU) 2016/1628.  
8 Only applicable f or engine (sub -)categories which have separate limits for HC and NOx according to Annex II of 
Regulation (EU) 2016/1628.  
9 Only applicable for engine (sub -)categories which have separate limits for HC and NOx according to Annex II of 
Regulation (EU) 2016/1 628. 
10 Only applicable for engine (sub -)categories which have a combined emission limit for HC + NOx according to 
Annex II of Regulation (EU) 2016/1628.  
11 Only applicable for engine (sub -)categories which have separate limits for HC and NOx according to Annex II of 
Regulation (EU) 2016/1628.  
12 Only applicable for engine (sub -)categories which have separate limits for HC and NOx according to Annex II of 
Regu lation (EU) 2016/1628.  
13 Only applicable for engine (sub -)categories which have a combined emission limit for HC + NOx according to 
Annex II of Regulation (EU) 2016/1628.  EN 34  EN I-2.2. CO mass [g/s]  
I-2.3. NOx mass [g/s]  
I-2.4. CO 2 mass [g/s]  
I-2.5. THC cumulated mass [g]  
I-2.6. CO cumulated mass [g]  
I-2.7. NOx cumulated mass [g]  
I-2.8. CO 2 cumulated mass [g]  
I-2.9. Calculated fuel rate [g/s]  
I-2.10. Engine power [kW]  
I-2.11. Engine work [kWh]  
I-2.12. Work averaging window duration [s]  
I-2.13. Work averaging window average eng ine power [%]  
I-2.14. Work averaging window THC conformity factor [ -] (14) 
I-2.15. Work averaging window CO conformity factor [ -]  
I-2.16. Work averaging window NOx conformity factor [ -] (15) 
I-2.17. Work averaging window THC+NOx conformity factor [ -] (16) 
I-2.18. CO 2 mass averaging window duration [s]  
I-2.19. CO 2 mass averaging window THC conformity factor [ -] (17) 
I-2.20. CO 2 mass averaging window CO conformity factor [ -]  
I-2.21. CO 2 mass averaging window NOx conformity factor [ -] (18) 
I-2.22. CO 2 mass ave raging window THC+NOx conformity factor [ -] (19)’; 
(27) The following Appendices 9 and 10 are added:  
‘Appendix 9  
Determination of reference work and reference CO 2 mass for engine types for which the 
applicable type -approval test cycle is solely a Non -Road Steady -State Cycle 
(NRSC)  
1. General  
                                                 
14 Only applicable for engine (sub -)categories which have separate limits for HC and  NOx in accordance with  [Please 
make change throughout footnotes .] Annex II of Regulation (EU) 2016/1628.  
15 Only applicable for engine (sub -)categories which have separate limits for HC and NOx according to Annex II of 
Regulation (EU) 2016/1628.  
16 Only app licable for engine (sub -)categories which have a combined emission limit for HC + NOx according to 
Annex II of Regulation (EU) 2016/1628.  
17 Only applicable for engine (sub -)categories which have separate limits for HC and NOx according to Annex II of 
Regul ation (EU) 2016/1628.  
18 Only applicable for engine (sub -)categories which have separate limits for HC and NOx according to Annex II of 
Regulation (EU) 2016/1628  
19 Only applicable for engine (sub -)categories which have a combined emission limit for HC + NOx  according to 
Annex II of Regulation (EU) 2016/1628.  EN 35  EN The reference work and reference mass of CO 2 for ISM groups A and C are taken 
from hot -start NRTC run of the type -approval test of the parent engine, and for ISM 
group H from the LSI -NRTC type -approval test of the paren t engine, as set out in 
point 2.1.2 of Appendix 5.  This Appendix defines how to determine the reference 
work and reference mass of CO 2 for engine types in all ISM groups except A, C and 
H. 
 For the purpose of this Appendix the applicable laboratory test c ycle shall be the 
discrete -mode NRSC or RMC NRSC for the corresponding engine (sub -)category set 
out in tables IV -1 and IV -2, and tables IV -5 to IV -10 of Annex IV to Regulation 
(EU) 2016/1628.  
2. Determination of Wref and 𝒎𝑪𝑶 𝟐,𝒓𝒆𝒇from RMC NRSC  
2.1. The reference work Wref ,kWh, is equal to the actual work Wact ,kWh, as given by 
Section 2.4.1.1 of Annex VII to Delegated Regulation  (EU)  2017/654 on technical 
and general requirements.  
2.2 The reference mass of CO 2 , 𝑚𝐶𝑂2,𝑟𝑒𝑓, g, is equal to the mass of CO 2 for the 
laboratory test cycle 𝑚𝐶𝑂2, g, calculated in accordance with  one of Section s 2.1.2, 
2.2.1, 3.5.1 or 3.6.1 of Annex VII to Delegated Regulation  (EU)  2017/654 on 
technical and general requirements according to whether raw or dilute gas eous 
sampling is used and whether mass -based or molar -based calculation is applied.  
 
3. Determination of Wref and 𝒎𝑪𝑶 𝟐,𝒓𝒆𝒇 from discrete -mode NRSC  
3.1. The reference work Wref , kWh shall be calculated using equation 9 -1. 
 
𝑊𝑟𝑒𝑓=∑ (𝑃𝑖∙𝑊𝐹 𝑖)𝑁𝑚𝑜𝑑𝑒
𝑖=1∙𝑡𝑟𝑒𝑓
3600 
(9-1) 
Where:  
Pi   is the engine power for mode i, kW, with Pi = P m,i + P AUX  (see Sections  6.3 
and 7.7.1.3 of Annex VI to Delegated Regulation  (EU)  2017/654 on technical 
and general requirements);  
 WF i  is the weighting factor for the mode i [ -]; 
 tref  is the reference time, s, (see table);  
Wref  is the reference cycle work emitted by the parent engine on the reference 
laboratory test cycle, kWh;  
 i  is the mode number;  
 Nmode is the total number of modes in the test cycle.  
3.2 The reference mass of CO 2 𝑚𝐶𝑂2,𝑟𝑒𝑓 , kg, shall be determined from the mean CO 2 
mass flow rate q mCO2,i  , g/h, for each mode i calculated in according with Sections 2 
or 3 of Annex VII to Delegated Regulation  (EU)  2017/654 on technical and general 
require ments using equation 9 -2. EN 36  EN 𝑚𝐶𝑂2,𝑟𝑒𝑓=∑ (𝑞𝑚𝐶𝑂2,𝑖∙𝑊𝐹 𝑖)𝑁𝑚𝑜𝑑𝑒
𝑖=1∙𝑡𝑟𝑒𝑓
3600 
(9-2) 
Where:  
𝑞𝑚𝐶𝑂2,𝑖 is the mean CO 2 mass flow rate for mode i, g/h;  
WF i  is the weighting factor for the mode i [-]; 
tref  is the reference time, s, (see table);  
𝑚𝐶𝑂2,𝑟𝑒𝑓 is the reference mass of CO 2 emitted by the parent engine on the reference 
laboratory test cycle, g;  
i  is the mode number;  
Nmode is the total number of modes in the test cycle  
 
3.3 Reference time tref is the total duration of the equivalen t Ramped Modal Cycle 
(RMC) set out in Appendix 2 to Annex XVII to Delegated Regulation  (EU)  
2017/654 on technical and general requirements.  Th ose values are set out in table.  
Table  
Reference time tref for each discrete -mode NRSC  
NRSC  tref [s] 
C1 1800  
C2 1800  
D2 1200  
E2 1200  
E3 1200  
F 1200  
G1 1800  
G2 1800  
H 1200  
 
  EN 37  EN Appendix 10  
Determination of the instantaneous proxy power from CO 2 mass flow  
 
1. General  
‘Proxy power’ means a value obtained by simple linear interpolation for the sole 
purpose of the determination of valid events during in -service monitoring as 
described in Appendix 4. This methodology is for engines designed without a 
communication interfac e capable to provide torque and speed data in accordance 
with Table 1 of Appendix 7. The calculation is based upon the assumption that , for 
all engine types within an engine family:  
(a)  the ratio of work and CO 2 mass on the reference laboratory test cycle  are 
similar;  
(b) there is a linear relationship between power and CO 2 mass flow rate; and,  
(c)  an operating engine that produces no net power emits no CO 2. 
2. Calculation of the instantaneous proxy power  
2.1. For the sole purpose of the calculations in Appendix 4 , an instantaneous power for 
the engine under ISM test shall be computed from the measured CO 2 mass flow at a 
time increment equal to the data sampling period. For this calculation a simplified 
engine -family -specific CO 2 (‘Veline ’) constant shall  be used.  
2.2 The Veline constant shall be calculated from the applicable reference values set out 
in point 2.1.2 of Appendix 5.  
 The Veline constant, Kveline, is computed from the reference mass of CO 2 emitted by 
the parent engine at type -approval divided  by the work performed by the parent 
engine at type -approval using equation 10 -1. 
𝐾𝑣𝑒𝑙𝑖𝑛𝑒 =𝑚𝐶𝑂2,𝑟𝑒𝑓
𝑊𝑟𝑒𝑓 
(10-1) 
Where:  
 
Kveline  is the “Veline” constant, g/kWh;  
𝑚𝐶𝑂2,𝑟𝑒𝑓  is the reference mass of CO 2 emitted by the parent engine in the 
reference laboratory test cycle , g; 
𝑊𝑟𝑒𝑓  is the reference work performed by the parent engine in the r eference 
laboratory test cycle, kWh.  
 
2.3  The instantaneous proxy power of the engine under ISM test is calcula ted from the 
instantaneous CO 2 mass flow using equation 10 -2   
 
𝑃𝑖,𝑝𝑟𝑜𝑥𝑦 =3600 ∙𝑚̇𝐶𝑂2,𝑖
𝐾𝑣𝑒𝑙𝑖𝑛𝑒 
(10-2) 
Where:  EN 38  EN  
Pi,proxy   is the instantaneous proxy power , kW; 
𝑚̇𝐶𝑂2,𝑖 is the instantaneous mass flow of CO 2 emitted by the engine under test , g/s.’.