Document ID: chunk:federal_register_of_legislation:F2023C00229:reg:9:p37
Version: federal_register_of_legislation:F2023C00229
Segment Type: reg
Provision Reference: reg 9 (pt 37/71)
Character Range: 312739–317736

described in this section for the components indicated in Annex III, Appendix 4, Section 5 and Annex V, Section 3.

4.2.                            Calibration procedure

4.2.1.                        Warming-up time

              The opacimeter shall be warmed up and stabilised according to the manufacturer's recommendations. If the opacimeter is equipped with a purge air system to prevent sooting of the instrument optics, this system should also be activated and adjusted according to the manufacturer's recommendations.

4.2.2.                        Establishment of the linearity response

              The linearity of the opacimeter shall be checked in the opacity readout mode as per the manufacturer's recommendations. Three neutral density filters of known transmittance, which shall meet the requirements of Annex III, Appendix 4, Section 5.2.5, shall be introduced to the opacimeter and the value recorded. The neutral density filters shall have nominal opacities of approximately 10 %, 20 % and 40 %.

              The linearity must not differ by more than ± 2 % opacity from the nominal value of the neutral density filter. Any non-linearity exceeding the above value must be corrected prior to the test.

4.3.                            Calibration intervals

              The opacimeter shall be calibrated according to Section 4.2.2 at least every three months or whenever a system repair or change is made that could influence calibration.

ANNEX IV

       TECHNICAL CHARACTERISTICS OF REFERENCE FUEL PRESCRIBED FOR APPROVAL TESTS AND TO VERIFY CONFORMITY OF PRODUCTION

    1.1.         DIESEL FUEL (1)

                                                                                          Limits (2)
     Parameter                                                           Unit                            Test method     Publication
  Minimum                                                                 Maximum
Cetane number (3)                                                                    52                  54            EN-ISO 5165             1998 (4)
Density at 15 °C                                                         kg/m3       833                 837           EN-ISO 3675             1995
Distillation:
— 50 % point                                                             °C          245              —                EN-ISO 3405             1998
— 95 % point                                                             °C          345                 350           EN-ISO 3405             1998
— final boiling point                                                    °C        —                     370           EN-ISO 3405             1998
Flash point                                                              °C          55               —                EN 27719                1993
CFPP                                                                     °C        —                     - 5           EN 116                  1981
Viscosity at 40 °C                                                       mm2/s       2,5                 3,5           EN-ISO 3104             1996
Polycyclic aromatic
hydrocarbons                                                             % m/m       3,0                 6,0           IP 391 (*)              1995
Sulphur content (5)                                                      mg/kg     —                     300           pr. EN-ISO/DIS 14596    1998 (4)
Copper corrosion                                                                   —                  1                EN-ISO 2160             1995
Conradson carbon residue
(10 % DR)                                                                % m/m     —                     0,2           EN-ISO 10370
Ash content                                                              % m/m     —                     0,01          EN-ISO 6245             1995
Water content                                                            % m/m     —                     0,05          EN-ISO 12937            1995
Neutralisation (strong acid)
number                                                                   mg KOH/g  —                     0,02          ASTM D 974-95           1998 (4)
Oxidation stability (6)                                                  mg/ml     —                     0,025         EN-ISO 12205            1996
 (*) New and better method for polycyclic aromatics under development
                                                                                                                                               [2000] (4)
                                                                         % m/m     —                  —                EN 12916

      (1)   If it is required to calculate the thermal efficiency of an engine or vehicle, the calorific value of the fuel can be calculated from:
      Specific energy (calorific value)(net) in MJ/kg = (46,423 - 8,792d2 + 3,170d)(1 - (x + y +