Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:13:p12
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 13 (pt 12/27)
Character Range: 582083–585279

100 nm electrical mobility diameter and a minimum concentration of 5,000 particles cm-3 at the VPR inlet. Particle concentrations shall be measured upstream and downstream of the components.
               The particle concentration reduction factor at each particle size (fr(di) ) shall be calculated as follows:
                         (117)
               Where:
                     Nin(di) = upstream particle number concentration for particles of diameter di
                     Nout(di) = downstream particle number concentration for particles of diameter di and
                     di = particle electrical mobility diameter (30, 50 or 100 nm)
                         Nin(di) and Nout(di) shall be corrected to the same conditions.
               The mean particle concentration reduction () at a given dilution setting shall be calculated as follows:
                  (118)
               It is recommended that the VPR is calibrated and validated as a complete unit.
              A.8.2.2.3. The Technical Service shall ensure the existence of a validation certificate for the VPR demonstrating effective volatile particle removal efficiency within a 6 month period prior to the emissions test. If the volatile particle remover incorporates temperature monitoring alarms a 12 month validation interval shall be permissible. The VPR shall demonstrate greater than 99.0 per cent removal of tetracontane (CH3(CH2)38CH3) particles of at least 30 nm electrical mobility diameter with an inlet concentration of ≥ 10,000 cm-3 when operated at its minimum dilution setting and manufacturers recommended operating temperature.
              A.8.2.3. Particle number system check procedures
              A.8.2.3.1. Prior to each test, the particle counter shall report a measured concentration of less than 0.5 particles cm-3 when a HEPA filter of at least class H13 of EN 1822:2008, or equivalent performance, is attached to the inlet of the entire particle sampling system (VPR and PNC).
              A.8.2.3.2. On a monthly basis, the flow into the particle counter shall report a measured value within 5 per cent of the particle counter nominal flow rate when checked with a calibrated flow meter.
              A.8.2.3.3. Each day, following the application of a HEPA filter of at least class H13 of EN 1822:2008, or equivalent performance, to the inlet of the particle counter, the particle counter shall report a concentration of ≤ 0.2 cm-3. Upon removal of this filter, the particle counter shall show an increase in measured concentration to at least 100 particles cm-3 when challenged with ambient air and a return to ≤ 0.2 cm-3 on replacement of the HEPA filter.
              A.8.2.3.4. Prior to the start of each test it shall be confirmed that the measurement system indicates that the evaporation tube, where featured in the system, has reached its correct operating temperature.
              A.8.2.3.5. Prior to the start of each test it shall be confirmed that the measurement system indicates that the diluter PND1 has reached its correct operating temperature.

Annex 5 Specifications of reference fuels
  Technical data on fuels for testing compression-ignition and