Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:10:p144
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 10 (pt 144/150)
Character Range: 1126438–1129519

of the i bins registered in the histogram.

              AE = effective ageing time, in hours, needed to achieve, by exposing the replacement pollution control device at the temperature Tr, the same amount of ageing as the one that would result from exposure of the replacement pollution control device during the duration of the thermal sequence.

              2.4.2.7. It is allowed to reduce NTS and, consequently the service accumulation schedule, by increasing the temperatures at which each device is exposed at each mode of the ageing cycle through the application of one or several of the following measures:

                  (a) Insulating the exhaust pipe;

                  (b) Moving the replacement pollution control device closer to the exhaust manifold;

                  (c) Artificially heating up the temperature of the exhaust;

                  (d) Optimizing the engine settings without substantially changing the emission behaviour of the engine.

              2.4.2.8. When applying the measures referred to in paragraphs 2.4.4.6. and 2.4.4.7., the total ageing time calculated from NTS shall not be less than 10 per cent of the useful life listed in Table 1, e.g. the vehicle category N1 shall not have an NTS of less than 286 thermal sequences, assuming that each sequence is 1 hour long.

              2.4.2.9. It is allowed to increase NTS and, consequently, the duration of the service accumulation schedule, by lowering the temperatures at each mode of the ageing cycle through the application of one or several of the following measures:

                  (a) Moving the replacement pollution control device further away from the exhaust manifold;

                  (b) Artificially cooling down the temperature of the exhaust;

                  (c) Optimizing the engine settings.

              2.4.2.10. In the case referred to in paragraph 2.4.1.5., the following shall apply:

              2.4.2.10.1. NTS shall be the same for each device, so that a single service accumulation schedule can be set up.

              2.4.2.10.2. In order to achieve the same NTS for each device, a first NTS value shall be calculated for each device, with its own AT and AE values.

              2.4.2.10.3. If the calculated NTS values are different, one or more of the measures set out in paragraphs 2.4.2.7. to 2.4.2.10. may be applied on the device or devices for which NTS needs to be modified, over the thermal sequences referred to in paragraph 2.4.2.3., in order to influence the measured Ti and therefore conveniently speed up or slow down the artificial ageing of the targeted device or devices.

              2.4.2.10.4. The new NTS values corresponding to the new temperatures Ti obtained in paragraph 2.4.2.10.3. shall be calculated.

              2.4.2.10.5. The steps set out in paragraphs 2.4.2.10.3. and 2.4.2.10.4. shall be repeated until the NTS values obtained for each device in the system match.

              2.4.2.10.6. The Tr values used for obtaining the different NTS in paragraphs 2.4.2.10.4. and 2.4.2.10.5. shall be