Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:10:p24
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 10 (pt 24/150)
Character Range: 781207–784325

long as the volatile particle removal efficiency meets the specifications set out in paragraph A.2.2.5.4.

              A.2.2.5.1.5. Pressure, temperature and other sensors shall monitor the operation of the instrument during its operation and shall trigger a warning or message in case of malfunction.

              A.2.2.5.1.6. The delay time inside the PM number analyser shall be < 5 s. Delay time means the time difference between a change of concentration at the reference point and a system response of 10 per cent of the final reading.

              A.2.2.5.1.7. The PM number analyser (and/or particle detector) shall have a rise time of < 3.5 s.

              A.2.2.5.1.8. Particle concentration measurements shall be reported normalised to 273 K (0 °C) and 101.3 kPa. If considered necessary using best engineering judgement, the pressure and/or temperature at the inlet of the detector shall be measured and reported for the purposes of normalising the particle concentration.

              A.2.2.5.1.9. PM number analysers that comply with the calibration requirements of UN Regulation No. 83 or UN Regulation No. 154 shall be deemed to comply with the calibration requirements of this annex.

              A.2.2.5.2. Efficiency requirements

              A.2.2.5.2.1. The complete PM number analyser system and the sampling line, shall meet the efficiency requirements of Table 1:

              Table 1
              PM number analyser system (and sampling line) efficiency requirements

dp [nm]  sub-23  23       30       50       70       100      200
E(dp)    - (*)   0.2-0.6  0.3-1.2  0.6-1.3  0.7-1.3  0.7-1.3  0.5-2.0

(*) Will be defined at a later stage
              A.2.2.5.2.2. Efficiency E(dp) is the ratio in the readings of the PM number analyser system to a reference Condensation Particle Counter (CPC)'s (d50 = 10 nm or lower, checked for linearity and calibrated with an electrometer) or an Electrometer's number concentration measuring in parallel monodisperse aerosol of mobility diameter dp and normalised at the same temperature and pressure conditions. The material shall be thermally stable and soot-like (e.g. spark discharged graphite or diffusion flame soot with thermal pre-treatment). If the efficiency curve is measured with a different aerosol (e.g. NaCl), the correlation to the soot-like curve shall be provided in the form of a chart which compares the efficiencies obtained using both test aerosols. The differences in the counting efficiencies shall be taken into account by adjusting the measured efficiencies based on that comparison chart to give soot-like aerosol efficiencies. Any correction for multiple charged particles shall be applied and documented, but it shall not exceed 10 per cent. The final efficiencies (e.g. adjusted for the different material and multiple charged particles) shall cover the PM number analyser and sampling line. The PM number analyser may alternatively be calibrated in parts (i.e. the pre-conditioning unit separately from the particle detector) provided that the PM number analyser and the sampling line together meet the