Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:10:p95
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 10 (pt 95/150)
Character Range: 990730–993383

the PEMS demonstration test shall be representative for the category of vehicle intended for the engine system. The vehicle may be a prototype vehicle.
7.3.2. At the request of the Type Approval Authority, an additional engine within the engine family or an equivalent engine representing a different vehicle category may be tested in a vehicle.
7.4. World-harmonized Not-To-Exceed laboratory testing
 Where the provisions of this annex are used as the basis for laboratory testing the following provision shall apply:
7.4.1. The specific mass emissions of regulated pollutants shall be determined on the basis of randomly defined test points distributed across the WNTE control area. All the test points shall be contained within 3 randomly selected grid cells imposed over the control area. The grid shall comprise of 9 cells for engines with a rated speed less than 3,000 min-1 and 12 cells for engines with a rated speed greater than or equal to 3,000 min-1. The grids are defined as follows:
(a) The outer boundaries of the grid are aligned to the WNTE control area;
(b) 2 vertical lines spaced at equal distance between engine speeds n30 and nhi for 9 cell grids, or 3 vertical lines spaced at equal distance between engine speeds n30 and nhi for 12 cell grids; and
(c) 2 lines spaced at equal distance of engine torque (⅓) at each vertical line within the WNTE control area.
 Examples of the grids applied to specific engines are shown in Figures 5 and 6.
7.4.2. The 3 selected grid cells shall each include 5 random test points, so a total of 15 random points shall be tested within the WNTE control area. Each cell shall be tested sequentially; therefore all 5 points in one grid cell are tested before transiting to the next grid cell. The test points are combined into a single ramped steady state cycle.
7.4.3. The order in which each of the grid cells are tested, and the order of testing the points within the grid cell, shall be randomly determined. The 3 grid cells to be tested, the 15 test points, the order of testing the grid cells, and the order of the points within a grid cell shall be selected by the Type approval or Certification Authority using acknowledged statistical methods of randomization.
7.4.4. The average specific mass emissions of regulated gaseous pollutants shall not exceed the WNTE limit values specified in paragraph 5.2. when measured over any of the cycles in a grid cell with 5 test points.
7.4.5. The average specific mass emissions of regulated particulate pollutants shall not exceed the WNTE limit values specified in paragraph 5.2. when measured over the whole 15 test point cycle.
7.5. Laboratory test