Document ID: chunk:federal_register_of_legislation:F2012C00283:reg:21:p15
Version: federal_register_of_legislation:F2012C00283
Segment Type: reg
Provision Reference: reg 21 (pt 15/39)
Character Range: 297939–301077

(THC) analysis - compression-ignition engines:
                The analyser shall be of the flame ionisation type with detector, valves, pipework, etc., heated to 463 K (190 °C) 10 K (HFID). It shall be calibrated with propane gas expressed equivalent to carbon atoms (C1).
              1.3.4.  Nitrogen oxide (NOx) analysis:
                The analyser shall be either of the chemi-luminescent (CLA) or of the non-dispersive ultra-violet resonance absorption (NDUVR) type, both with NOx-NO converters.
              1.3.5.  Methane (CH4) analysis:
                The analyser shall be either a gas chromatograph combined with a flame ionisation (FID), or a flame ionisation (FID) with a non-methane cutter type, calibrated with methane gas expressed equivalent to carbon atoms (C1).
              1.3.6.  The analysers shall have a measuring range compatible with the accuracy required to measure the concentrations of the exhaust gas sample pollutants.
              1.3.7. Measurement error shall not exceed 2 per cent (intrinsic error of analyser) disregarding the true value for the calibration gases.
              1.3.8.  For concentrations of less than 100 ppm, the measurement error shall not exceed 2 ppm.
              1.3.9. The ambient air sample shall be measured on the same analyser with an appropriate range.
              1.3.10. No gas drying device shall be used before the analysers unless shown to have no effect on the pollutant content of the gas stream.
              1.4.  Recommended System Descriptions
               Figure 10 is a schematic drawing of the system for gaseous emissions sampling.

Figure 10
Gaseous Emissions Sampling Schematic

               The components of the system are as follows:
              1.4.1.  Two sampling probes (S1 and S2) for continuous sampling of the dilution air and of the diluted exhaust-gas/air mixture;
              1.4.2.  A filter (F), to extract solid particles from the flows of gas collected for analysis;
              1.4.3.  Pumps (P), to collect a constant flow of the dilution air as well as of the diluted exhaust-gas/air mixture during the test;
              1.4.4.  Flow controller (N), to ensure a constant uniform flow of the gas samples taken during the course of the test from sampling probes S1 and S2 (for PDP-CVS) and flow of the gas samples shall be such that, at the end of each test, the quantity of the samples is sufficient for analysis (approximately 10 litres per minute);
              1.4.5.  Flow meters (FL), for adjusting and monitoring the constant flow of gas samples during the test;
              1.4.6.  Quick-acting valves (V), to divert a constant flow of gas samples into the sampling bags or to the outside vent;
              1.4.7.  Gas-tight, quick-lock coupling elements (Q) between the quick-acting valves and the sampling bags; the coupling shall close automatically on the sampling-bag side; as an alternative, other ways of transporting the samples to the analyser may be used (three-way stopcocks, for instance);
              1.4.8.  Bags (B), for collecting samples of the diluted exhaust gas and of the