# Commission Regulation (EU) 2017/1151 of 1 June 2017 supplementing Regulation (EC) No 715/2007 of the European Parliament and of the Council on type-approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5 and Euro 6) and on access to vehicle repair and maintenance information, amending Directive 2007/46/EC of the European Parliament and of the Council, Commission Regulation (EC) No 692/2008 and Commission Regulation (EU) No 1230/2012 and repealing Commission Regulation (EC) No 692/2008 (Text with EEA relevance), Division 1.2: Definitions


1.2.1.‘Accuracy’ means the deviation between a measured or calculated value and a traceable reference value.
1.2.2.‘Analyser’ means any measurement device that is not part of the vehicle but installed to determine the concentration or the amount of gaseous or particle pollutants.
1.2.3.‘Axis intercept’ of a linear regression (a0) means:
a0=y–−a1×x–where:
a1is the slope of the regression line
x–is the mean value of the reference parameter
y–is the mean value of the parameter to be verified
1.2.4.‘Calibration’ means the process of setting the response of an analyser, flow-measuring instrument, sensor, or signal so that its output agrees with one or multiple reference signals.
1.2.5.‘Coefficient of determination’ (r2) means:
r2=1−∑ni= 1yi− a0−a1× xi2∑ni= 1yi−y–2where:
a0is the axis intercept of the linear regression line
a1is the slope of the linear regression line
xiis the measured reference value
yiis the measured value of the parameter to be verified
y–is the mean value of the parameter to be verified
nis the number of values
1.2.6.‘Cross-correlation coefficient’ (r) means:
r=∑n− 1i= 1xi−x–×yi−y–∑n− 1i= 1xi−x–2×∑n− 1i= 1yi−y–2where:
xiis the measured reference value
yiis the measured value of the parameter to be verified
x–is the mean reference value
y–is the mean value of the parameter to be verified
nis the number of values
1.2.7.‘Delay time’ means the time from the gas flow switching (t0) until the response reaches 10 per cent (t10) of the final reading.
1.2.8.‘Engine control unit (ECU) signals or data’ means any vehicle information and signal recorded from the vehicle network using the protocols specified in point 3.4.5.of Appendix 1.
1.2.9.‘Engine control unit’ means the electronic unit that controls various actuators to ensure the optimal performance of the powertrain.
1.2.10.‘Emissions’ also referred to as ‘components’, ‘pollutant components’ or ‘pollutant emissions’ means the regulated gaseous or particle constituents of the exhaust.
1.2.11.‘Exhaust’, also referred to as exhaust gas, means the total of all gaseous and particulate components emitted at the exhaust outlet or tailpipe as the result of fuel combustion within the vehicle’s internal combustion engine.
1.2.12.‘Exhaust emissions ’ means the tailpipe emissions of gaseous, solid and liquid compounds.
1.2.13.‘Full scale’ means the full range of an analyser, flow-measuring instrument or sensor as specified by the equipment manufacturer. If a sub-range of the analyser, flow-measuring instrument or sensor is used for measurements, full scale shall be understood as the maximum reading.
1.2.14.‘Hydrocarbon response factor’ of a particular hydrocarbon species means the ratio between the reading of a FID and the concentration of the hydrocarbon species under consideration in the reference gas cylinder, expressed as ppmC1.
1.2.15.‘Major maintenance’ means the adjustment, repair or replacement of an analyser, flow-measuring instrument or sensor that could affect the accuracy of measurements.
1.2.16.‘Noise ’ means two times the root mean square of ten standard deviations, each calculated from the zero responses measured at a constant frequency which is a multiple of 1,0 Hz during a period of 30 seconds.
1.2.17.‘Non-methane hydrocarbons’ (NMHC) means the total hydrocarbons (THC) excluding methane (CH4).
1.2.18.‘Particle number emissions ’ (PN) means the total number of solid particles emitted from the vehicle exhaust quantified according to the dilution, sampling and measurement methods as specified in Annex XXI.
1.2.19.‘Precision’ means 2.5 times the standard deviation of 10 repetitive responses to a given traceable standard value.
1.2.20.‘Reading’ means the numerical value displayed by an analyser, flow-measuring instrument, sensor or any other measurement devise applied in the context of vehicle emission measurements.
1.2.21.‘Response time’ (t90) means the sum of the delay time and the rise time.
1.2.22.‘Rise time’ means the time between the 10 per cent and 90 per cent response (t90 – t10) of the final reading.
1.2.23.‘Root mean square’ (xrms) means the square root of the arithmetic mean of the squares of values and defined as:
xrms=1nx21+ x22+ …+ x2nwhere:
xis the measured or calculated value
nis the number of values
1.2.24.‘Sensor’ means any measurement device that is not part of the vehicle itself but installed to determine parameters other than the concentration of gaseous and particle pollutants and the exhaust mass flow.
1.2.25.‘Span ’ means to adjust an instrument so that it gives a proper response to a calibration standard that represents between 75 per cent and 100 per cent of the maximum value in the instrument range or expected range of use.
1.2.26.‘Span response’ means the mean response to a span signal over a time interval of at least 30 seconds.
1.2.27.‘Span response drift’ means the difference between the mean response to a span signal and the actual span signal that is measured at a defined time period after an analyser, flow-measuring instrument or sensor was accurately spanned.
1.2.28.‘Slope’ of a linear regression (a1) means:
a1=∑ni= 1yi−y–×xi−x–∑ni= 1xi−x–2where:
x–is the mean value of the reference parameter
y–is the mean value of the parameter to be verified
xiis the actual value of the reference parameter
yiis the actual value of the parameter to be verified
nis the number of values
1.2.29.‘Standard error of estimate’ (SEE) means:
SEE=1xmax×∑ni= 1yi− ý2n− 2where:
ýis the estimated value of the parameter to be verified
yiis the actual value of the parameter to be verified
xmaxis the maximum actual value of the reference parameter
nis the number of values
1.2.30.‘Total hydrocarbons’ (THC) means the sum of all volatile compounds measurable by a flame ionization detector (FID).
1.2.31.‘Traceable’ means the ability to relate a measurement or reading through an unbroken chain of comparisons to a known and commonly agreed standard.
1.2.32.‘Transformation time’ means the time difference between a change of concentration or flow (t0) at the reference point and a system response of 50 per cent of the final reading (t50).
1.2.33.‘Type of analyser’, also referred to as ‘analyser type’ means a group of analysers produced by the same manufacturer that apply an identical principle to determine the concentration of one specific gaseous component or the number of particles.
1.2.34.‘Type of exhaust mass flow meter’ means a group of exhaust mass flow meters produced by the same manufacturer that share a similar tube inner diameter and function on an identical principle to determine the mass flow rate of the exhaust gas.
1.2.35.‘Validation’ means the process of evaluating the correct installation and functionality of a Portable Emissions Measurement System and the correctness of exhaust mass flow rate measurements as obtained from one or multiple non-traceable exhaust mass flow meters or as calculated from sensors or ECU signals.
1.2.36.‘Verification’ means the process of evaluating whether the measured or calculated output of an analyser, flow-measuring instrument, sensor or signal agrees with a reference signal within one or more predetermined thresholds for acceptance.
1.2.37.‘Zero’ means the calibration of an analyser, flow-measuring instrument or sensor so that it gives an accurate response to a zero signal.
1.2.38.‘Zero response’ means the mean response to a zero signal over a time interval of at least 30 seconds.
1.2.39.‘Zero response drift’ means the difference between the mean response to a zero signal and the actual zero signal that is measured over a defined time period after an analyser, flow-measuring instrument or sensor has been accurately zero calibrated.
1.2.40.‘Off-vehicle charging hybrid electric vehicle’ (OVC-HEV) means a hybrid electric vehicle that can be charged from an external source.
1.2.41.‘Not off-vehicle charging hybrid electric vehicle’ (NOVC-HEV) means a vehicle with at least two different energy converters and two different energy storage systems that are used for the purpose of vehicle propulsion and that cannot be charged from an external source.

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Source: https://www.legislation.gov.uk/eur/2017/1151/annex/IIIA/division/1/division/1.2 (the official version)
Page: https://openlegislation.uk/eu-regulation-2017-1151/annex-IIIA/division-1/division-1.2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.