Document ID: chunk:federal_register_of_legislation:F2022C00213:reg:120:p39
Version: federal_register_of_legislation:F2022C00213
Segment Type: reg
Provision Reference: reg 120 (pt 39/56)
Character Range: 261577–266278

decision number for the sample given in table 1, a pass decision is reached;

        9.3.2.5.2. if the test statistic is less than the fail decision number for the sample size given in table 1, a fail decision is reached;

        9.3.2.5.3. otherwise, an additional vehicle is tested according to Annex 6 and the procedure is applied to the sample with one unit more.

        Table 1

 Sample Size                                     Pass Decision No.          Fail Decision No.
 (cumulative number of vehicles tested)

        (a)                                      (b)                        (c)

        3                                        3.327                      - 4.724
        4                                        3.261                      - 4.790
        5                                        3.195                      - 4.856
        6                                        3.129                      - 4.922
        7                                        3.063                      - 4.988
        8                                        2.997                      - 5.054
        9                                        2.931                      - 5.120
        10                                       2.865                      - 5.185
        11                                       2.799                      - 5.251
        12                                       2.733                      - 5.317
        13                                       2.667                      - 5.383
        14                                       2.601                      - 5.449
        15                                       2.535                      - 5.515
        16                                       2.469                      - 5.581
        17                                       2.403                      - 5.647
        18                                       2.337                      - 5.713
        19                                       2.271                      - 5.779
        20                                       2.205                      - 5.845
        21                                       2.139                      - 5.911
        22                                       2.073                      - 5.977
        23                                       2.007                      - 6.043
        24                                       1.941                      - 6.109
        25                                       1.875                      - 6.175
        26                                       1.809                      - 6.241
        27                                       1.743                      - 6.307
        28                                       1.677                      - 6.373
        29                                       1.611                      - 6.439
        30                                       1.545                      - 6.505
        31                                       1.479                      - 6.571
        32                                       - 2.112                    - 2.112

        9.3.3. Conformity of production when manufacturer's statistical data is unsatisfactory or unavailable.

        9.3.3.1. The following sections describe the procedure to be used to verify the CO2 conformity of production requirements when the manufacturer's evidence of production standard deviation is either unsatisfactory or unavailable.

        9.3.3.2. With a minimum sample size of three the sampling procedure is set so that the probability of a lot passing a test with 40 per cent of the production defective is 0.95 (producer's risk = 5 per cent) while the probability of a lot being accepted with 65 per cent of the production defective is 0.1 (consumer's risk = 10 per cent).

        9.3.3.3. The measurement of CO2 is considered to be log normally distributed and should first be transformed by taking the natural logarithms.  Let mo and m denote the minimum and maximum sample sizes respectively (mo = 3 and m = 32) and let n denote the current sample number.

        9.3.3.4. If the natural logarithms of the measurements in the series are x1, x2, ..., xj and L is the natural logarithm of the CO2 type approval value, then define:

        9.3.3.5. Table 2 shows values of the pass (An) and fail (Bn) decision numbers against current sample number.  The test statistic is the ratio  and shall be used to determine whether the series has passed or failed as follows:

         for mo  n  m:

        9.3.3.5.1. pass the series if ;

        9.3.3.5.2. fail the series if ;

        9.3.3.5.3. take another measurement if .

        Table