ANNEX III

TYPE I TEST (verifying the average emission of pollutants in a congested urban area after a cold start) Procedure for Type I test specified in item 3.2.1.1. of Annex I 1. OPERATING CYCLE ON THE DYNAMOMETER BENCH 1.1. Description of cycle The operating cycle on the dynamometer bench shall be that indicated in the following table and plotted in Appendix 1. The analysis by operations is given in Appendix 2. >PIC FILE= "T0002125"> 1.2. General conditions for carrying out the cycle Preliminary testing cycles should be carried out if necessary to determine how best to actuate the accelerator and brake controls so as to achieve a cycle approximating to the theoretical cycle within the prescribed limits. 1.3. Use of the gearbox 1.3.1. If the maximum speed which can be attained in first gear is below 15 km/h, the second, third and fourth gears shall be used. 1.3.2. Vehicles equipped with semi-automatic gearboxes shall be tested by using the ratios normally employed for driving, and the gear lever shall be operated in accordance with the manufacturer's instructions. 1.3.3. Vehicles equipped with fully automatic gearboxes shall be tested with the highest gear ("Drive") engaged. The accelerator shall be operated so as to obtain the steadiest acceleration possible, allowing the various gears to be engaged in the normal order. Furthermore, the gear-change points shown in Appendix 1 shall not apply ; acceleration shall continue throughout the period represented by the straight lines connecting the end of each period of idling with the beginning of the next period of steady speed. The tolerances given in item 1.4 shall apply. 1.3.4. Vehicles equipped with an overdrive-which can be actuated by the driver shall be tested with the overdrive out of action. 1.4. Tolerances 1.4.1. A tolerance of 1 km/h above or below the theoretical speed shall be allowed during acceleration during steady speed, and during deceleration when the vehicle's brakes are applied. If the vehicle decelerates more rapidly without the use of the brakes, only the requirements of item 5.6.3 shall apply. Speed tolerances greater than those prescribed shall be permitted during phase changes provided that the tolerances are never exceeded for more than 0.5 second on any one occasion. 1.4.2. Time tolerances of ± 0 7 5 sec. These tolerances shall apply at the beginning and at the end of each gear-changing period.(1) 1.4.3. The speed and time tolerances shall be combined as indicated in Appendix 1. 2. VEHICLE AND FUEL 2.1. Test vehicle 2.1.1. The vehicle shall be presented in good mechanical condition. It shall have been run in and have been driven at least 3000 km before the test. 2.1.2. The exhaust device shall not have any leaks likely to reduce the quantity of gases collected, which shall be the quantity of gases emerging from the engine. 2.1.3. The tightness of the admission system may be checked to ensure that carburation is not affected by an accidental intake of air. 2.1.4. The settings of the engine and of the vehicle's controls shall be those prescribed by the manufacturer. 2.1.5. A vacuum gauge shall be installed in the intake circuit near the carburettor, beyond the throttle. 2.1.6. The laboratory may verify that the vehicle conforms to the performances stated by the manufacturer, that it can be used for normal driving, and more particularly that it is capable of starting when cold and when hot. 2.2. Fuel 2.2.1. The fuel shall be the reference fuel whose specifications ate given in Annex VI. If the engine is lubricated by a mixture, the oil added to the reference fuel shall comply as to grade and quantity with the manufacturer's recommendations. (1)It should be noted that the time of two seconds allowed includes the time for changing gear and, if necessary, a certain amount of latitude to catch up with the cycle. 3. TEST EQUIPMENT 3.1. Dynamometer brake No particular model is prescribed. However, its adjustment shall not be affected by the lapse of time. It shall not produce any perceptible vibrations in the vehicle likely to impair the latter's normal operation. It must be equipped with an inertia adapter enabling the operation of the vehicle on the road to be reproduced (equivalent inertias). 3.2. Gas-collection equipment 3.2.1. The connecting tubes shall be made of steel and shall, so far as possible, be provided with rigid connections. However, a completely gas-tight flexible ring element shall be used to isolate the device from the vehicle vibrations. Other materials may be used if they do not affect the composition of the gases. 3.2.2. If the vehicle being tested is equipped with an exhaust pipe comprising several branches, the branches shall be interlinked as near as possible to the vehicle. 3.2.3. The temperature of the gases in the collecting system shall be compatible with the correct operation of the engine, with maintenance of the sampling bags in good condition, with the hydrocarbon absorption level laid down in item 4.5.1 and with the reduction to a minimum of condensation on the sides of the sampling bag or bags. 3.2.4. The various valves used to direct the exhaust gases either to the atmosphere or to the sampling device shall be quickly adjustable and quick-acting. 3.2.5. The collecting device shall comprise one or more bags of adequate capacity. The bags shall be made of such materials as will not affect either the accuracy of the measurements or the conservation of the gases. 3.3. Analytical equipment 3.3.1. The sampling probe may consist of the sampling tube leading into the collecting device or of the bag-emptying tube. It may also be independent but in no case shall its opening be at the bottom of the bag. 3.3.2. Analysers shall be of the non-dispersive type with absorption in the infra-red. The hydrocarbons analyser shall be sensitised for n-hexane. 3.4. Volume-measuring equipment 3.4.1. A volumetric gauge shall be used. 3.4.2. Pressure and temperature measurements enabling the volume to be referred to standard conditions shall be carried out at points selected in the light of the type of gauge used. The laboratory shall specify their positions. 3.4.3. The gas-bleeding device may consist of a pump or of any other system which keeps the pressure measured at the gauge constant. 3.5. Accuracy of instruments 3.5.1. As the brake is calibrated in a separate test, the accuracy of the dynamometer is not indicated. The total inertia of the rotating masses, including that of the rollers and the rotating part of the brake (see item 4.2), shall be given to within ± 20 kg. 3.5.2. The speed of the vehicle shall be measured by the speed of rotation of the rollers connected to the brake flywheels. It shall be measurable to within ± 2 km/h in the speed range 0 to 10 km/h and to within ± 1 km/h for speeds above 10 km/h. 3.5.3. The temperatures considered in items 5.1.1 and 6.3.3 shall be measurable to within ± 2º C. 3.5.4. The atmospheric pressure shall be measurable to within ± 1 mm of mercury. 3.5.5. The vacuum in the vehicle's intake system shall be measurable to within ± 5 mm of mercury. The other pressures (backpressure in the sampling device, pressure for correction of volume etc.) must be measurable to within ± 5 mm water gauge. 3.5.6. The size and accuracy of the gauge shall be appropriate to the volume of gas to be measured, so that the measurement of volume is accurate to within ± 2 %. 3.5.7. The analysers shall have a measuring range compatible with the accuracy required to measure the content of the various constituents to within ± 3 %, disregarding the accuracy of the standard (calibration) gases. The overall response time of the analysing circuit shall be less than one minute. 3.5.8. The content of the standard gases shall not differ by more than ± 2 % from the reference value of each gas. The diluent shall be nitrogen. 4. PREPARING THE TEST 4.1. Setting of brake 4.1.1. The brake shall be so adjusted as to reproduce the operation of the vehicle on the level at a steady speed of 50 km/h. 4.1.2. For this purpose the vacuum shall be measured at the engine intake during a road test carried out at 50 km/h in third gear, or using the gears specified in item 1.3, the vehicle being loaded to its reference weight and the tyre pressure being that indicated by the manufacturer. The vacuum shall be measured when a steady speed on the level has been maintained for at least fifteen seconds. To take account of the effects of wind, the average of the results of measurements made twice in each direction shall be taken. 4.1.3. The vehicle shall then be placed on the dynamometer bench and the brake so adjusted as to obtain the same vacuum at the intake as that recorded in the road test referred to item 4.1.2 above. This brake setting shall be maintained throughout the test. 4.1.4. This setting is appropriate for brakes of hydraulic type. For other types it may be necessary to make sure that the setting so obtained is appropriate for other intermediate states between idling and the maximum speed in the cycle. If necessary, an average setting shall be adopted. 4.2. Adjustment of equivalent inertias to the vehicle's translatory inertias A flywheel shall be used enabling a total inertia of the rotating masses to be obtained proportional to the reference weight within the following limits: >PIC FILE= "T0002126"> 4.3. Conditioning of vehicle 4.3.1. Before the test the vehicle shall be kept at a temperature of between 20º and 30º C for at least six hours. The cooling-water and engine-oil temperatures shall be measured before the test to make sure that they are between 20º and 30º C. 4.3.2. The tyre pressure shall, as in the case of the preliminary road test for brake adjustment, be that indicated by the manufacturer. However, if the diamter of the rollers is less than 50 cm, the pressure in the tyres shall be increased by 30-50 % to prevent damage to the tyres. 4.4. Check of back-pressure During the preliminary tests a check shall be made to ensure that the back-pressure set up by the sampling device does not exceed 75 mm water gauge, measurements being performed at the various steady speeds prescribed in the cycle. 4.5. Conditioning of bags 4.5.1. The bags shall be so conditioned, particularly with regard to hydrocarbons, that hydrocarbon losses over a period of 20 minutes do not exceed 2 % of the initial content. This conditioning shall be carried out during preliminary tests conducted at temperatures close to the extreme temperatures encountered during the various tests. 4.5.2. Losses shall be measured as follows. When the engine is running at a constant (rpm) speed the hydrocarbon content of the gases entering the bag shall be measured continuously until the bag has been filled. The content, when filling is completed, must be the average of the contents recorded during filling. The bag shall be emptied by the analyser pumps and the content recorded continuously or at fixed intervals. If after twenty minutes the content has varied by more than 2 %, the bag shall be emptied and then refilled for a second measurement. This cycle shall be repeated as many times as is necessary to saturate the walls. 4.6. Calibration of analytical apparatus 4.6.1. Calibration of analysers. The quantity of gas at the indicated pressure compatible with the correct functioning of the equipment shall be injected into the analyser by means of the discharge gauge and the pressure-reducing valve mounted on each bottle. The apparatus shall be adjusted to indicate as a stabilised value the value shown on the standard-gas bottle. Starting from the setting obtained with the maximum-content bottle, the curve of the analyser's deviations shall be drawn as a function of the content of the various standard-gas bottles used. 4.6.2. Overall response time of the apparatus. The gas from the maximum-content bottle shall be injected into the end of the sampling probe. A check shall be made to ensure that the indicated value corresponding to maximum deviation is attained in less than one minute. If this value is not attained, the analysing circuit shall be inspected from end to end for leaks. 4.7. Adjustment of volume-measuring device The bag shall be filled during the preliminary tests and a check made to ensure that the volume can be measured with the desired accuracy. If necessary, a suitable (gas) gauge shall be selected in each case. 5. PROCEDURE FOR BENCH TESTS 5.1. Special conditions for carrying out the cycle 5.1.1. The temperature in the place where the roller bench is situated shall be between 20º and 30º C throughout the test and approximate as closely as possible that of the place where the vehicle was conditioned for the test. 5.1.2. The vehicle shall be more or less horizontal during the test so as to avoid any abnormal distribution of the fuel. 5.1.3. The test shall be carried out with the bonnet raised. An auxiliary ventilating device acting on the radiator (water-cooled) or on the air intake (air-cooled) may be used, if necessary, to keep the engine temperature normal. 5.1.4. When the cycle is carried out the speed considered shall be that of the rollers connected to the brake flywheel. During the test the speed shall be plotted against time so that the correctness of the cycles performed can be assessed. 5.1.5. Recording of the vacuum shall be optional ; however, if it is recorded at the same time as the speed, it will be possible to judge whether the accelerations have been made correctly. 5.1.6. The temperatures of the cooling water and of the crankcase oil may also be recorded if desired. 5.2. Starting up the engine 5.2.1. The engine shall be started up by means of the devices provided for this purpose, such as the choke, the starter valve, etc., according to the manufacturer's instructions. 5.2.2. The engine shall be kept idling on the choke for a period of forty seconds. The first cycle shall begin when the valve of the effluent-recovery device is operated, which shall be done at the end of the forty-second period. 5.3. Use of the manual choke The choke shall be cut out as soon as possible, and in principle before acceleration from 0 to 50 km/h. If this requirement cannot be met, the moment of effective cut-out shall be indicated. The method used to adjust the choke shall be that indicated by the manufacturer. 5.4. Idling 5.4.1. Manual-shift gearbox: 5.4.1.1. During periods of idling the clutch shall be engaged and the gears in neutral. 5.4.1.2. To enable the accelerations to be performed according to the normal cycle the vehicle shall be put in first gear, with the clutch disengaged, five seconds before the acceleration following the idling period in question. 5.4.1.3. The first idling period at the beginning of the cycle shall consist of six seconds of idling in neutral with the clutch engaged and five seconds in first gear with the clutch disengaged. 5.4.1.4. For the idling periods during each cycle the corresponding times shall be sixteen seconds in neutral and five seconds in first gear with the clutch disengaged. 5.4.1.5. The last idling period in the cycle shall consist of seven seconds in neutral with the clutch engaged. 5.4.2. Semi-automatic gearboxes: The manufacturer's instructions for driving in town, or in their absence instructions applicable to manual gearboxes, shall be followed. 5.4.3. Automatic gearboxes: The selector must not be operated at any time during the test unless the manufacturer specifies otherwise. In the latter case the procedure for manual gearboxes shall be applied. 5.5. Accelerations 5.5.1. Accelerations shall be so performed that the rate of acceleration is as constant as possible through-out the operation. 5.5.2. If acceleration cannot be carried out in the prescribed time, the extra time required shall be deducted from the time allowed for changing the combination, if possible, and in any case from the next steady-speed period. 5.6. Decelerations 5.6.1. All decelerations shall be effected by removing the foot completely from the accelerator, the clutch remaining engaged. The clutch shall be disengaged, without touching the gear lever, at a speed of 10 km/h. 5.6.2. If the period of deceleration is longer than that prescribed for the corresponding phase, the vehicle's brakes shall be used to keep to the cycle. 5.6.3. If the period of deceleration is shorter than that prescribed for the corresponding phase, the timing of the theoretical cycle shall be restored by an idling period merging into the following idling operation. 5.6.4. At the end of the deceleration period (stopping vehicle on the rollers) the gear shall be put into neutral and the clutch engaged. 5.7. Steady speeds 5.7.1. "Pumping" or the closing of the throttle shall be avoided when passing from acceleration to the following steady speed. 5.7.2. Periods of constant speed shall be achieved by keeping the accelerator position fixed. 6. PROCEDURE FOR SAMPLING AND ANALYSIS 6.1. Sampling 6.1.1. Sampling shall begin as soon as the valve has been opened as indicated in item 5.2.2. 6.1.2. If several bags are used the bag shall be changed at the beginning of the first idling period of a cycle. 6.1.3. The bag shall be hermetically closed as soon as it is full. 6.1.4. At the end of the last cycle the valve shall be operated to divert the gases produced by the engine into the atmosphere. 6.2. Analysis 6.2.1. The gases contained in each bag shall be analysed as soon as possible and in any event not later than twenty minutes after filling of the bag in question began. 6.2.2. If the sampling probe is not left permanently in the bag, the entry of air into the latter during insertion of the probe and the escape of gases from the bag during extraction of the probe should be avoided. 6.2.3. The analyser shall be in a stabilised condition within one minute of its connection to the bag. 6.2.4. The figure adopted as the content of the gases in each of the effluents measured shall be that read off after stabilisation of the measuring instrument. 6.3. Measurement of volume 6.3.1. To avoid wide temperature variations, the volume of the bag or bags shall be measured as soon as the gases have reached room temperature. 6.3.2. The bags shall be emptied by passing the gases through the gas gauge. 6.3.3. The temperature (tm) used for the calculations shall be the arithmetic mean of the temperatures at the beginning and at the end of emptying, the maximum permissible difference between these two temperatures being less than 5 ºC. 6.3.4. The pressure (Pm) used for the calculations shall be the arithmetic mean of the absolute pressures recorded beginning and at the end of emptying, the maximum permissable difference between these two pressures being less than 4 mm of mercury. 6.3.5. The volume of gas drawn off for analysis shall be added to the volume measured by the meter if the first volume is equivalent to more than 1 per cent of the measured volume. The result obtained shall be designated by the symbol Vm. 7. DETERMINATION OF THE QUANTITY OF GASEOUS POLLUTANTS EMITTED 7.1. Correction of the measured volumes of gas The volume of the gases contained in each bag shall be referred to normal temperature and pressure by means of the formula: >PIC FILE= "T0002127"> Vm : is the volume, expressed in litres, recorded as indicated in item 6.3.5; tm : is the arithmetic mean of the extreme temperatures recorded as indicated in item 6.3.3, expressed in degrees Celsius; Pm : is the arithmetic mean of the extreme absolute pressures recorded as indicated in item 6.3.4, expressed in millimetres of mercury ; and PH : is the saturated-water-vapour pressure, expressed in millimetres of mercury, at temperature Tm. 7.2. Mass of the gaseous pollutants contained in each bag The mass of the gaseous pollutants contained in each bag shall be determined by the product dCV, where C is the content by volume and d the volume mass of the gaseous pollutant considered : - in the case of carbon monoxide, d = 1 7 250; in the case of hydrocarbons, d = 3 7 844 (n-hexane). 7.3. Total mass of gaseous pollutants emitted The mass M of each gaseous pollutant emitted by the vehicle during the test shall be determined by adding the masses of the gaseous pollutants contained in each bag and calculated as indcated in item 7.2. Note : Laboratories are recommended to check the analyses by also measuring the quantity of carbon dioxide produced. APPENDIX 1 >PIC FILE= "T0002128"> APPENDIX 2 Analysis of the operating cycle used for the type I test >PIC FILE= "T0002129"> Average speed during test : 19 km/h. Effective running time : 195 sec. Theoretical distance covered per cycle : 1 7 013 km. Equivalent distance for the test (4 cycles) : 4 7 052 km.

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Source: EUR-Lex (Cellar) · retrieved 2026-11-01 · Text as adopted (Official Journal); later amendments are not incorporated in this text.