Document ID: chunk:federal_register_of_legislation:F2023C00229:reg:9:p42
Version: federal_register_of_legislation:F2023C00229
Segment Type: reg
Provision Reference: reg 9 (pt 42/71)
Character Range: 330439–333327

sufficiently distant (radially) from other probes and the tunnel wall so as to be free from  the  influence of any wakes or eddies;
                —    be heated and insulated over its entire length to a minimum temperature of 328 K (55 °C) to prevent water condensation.

              HSL1 Heated sampling line

              The sampling line provides a gas sample from a single probe to the split point(s) and the HC analyser. The sampling line shall:
                —    have a 5 mm minimum and a 13,5 mm maximum inside diameter;

                —    be made of stainless steel or PTFE;

                —    maintain a wall temperature of 463 K ± 10 K (190 °C ± 10 °C) as measured at every separately controlled heated section, if the temperature of the exhaust gas at the sampling probe is equal to or below 463 K (190 °C);

                —    maintain a wall temperature greater than 453 K (180 °C), if the temperature of the exhaust gas at the sampling probe is above 463 K (190 °C);

                —    maintain a gas temperature of 463 K ± 10 K (190 °C ± 10 °C) immediately before the heated filter  F2 and the HFID.

              HSL2 Heated NOx sampling line

              The sampling line shall:

                —    maintain a wall temperature of 328 K to 473 K (55 °C to 200 °C), up to the converter C when using a cooling bath B, and up to the analyser when a cooling bath B is not used,

                —    be made of stainless steel or PTFE.

              SL Sampling line for CO and CO2

              The line shall be made of PTFE or stainless steel. It may be heated or unheated.

              BK Background bag (optional; Figure 8 only)

              For the sampling of the background concentrations.

              BG Sample bag (optional; Figure 8 CO and CO2 only)

              For the sampling of the sample concentrations.

              F1 Heated pre-filter (optional)

              The temperature shall be the same as HSL1.

              F2 Heated filter

              The filter shall extract any solid particles from the gas sample prior to the analyser. The temperature shall be the same as HSL1. The filter shall be changed as needed.

              P Heated sampling pump

              The pump shall be heated to the temperature of HSL1.

              HC

              Heated flame ionisation detector (HFID) for the determination of the hydrocarbons. The temperature shall be kept at 453 K to 473 K (180 °C to 200 °C).

              CO, CO2

              NDIR analysers for the determination of carbon monoxide and carbon dioxide (optional for the determination of the dilution ratio for PT measurement).

              NO

              CLD or HCLD analyser for the determination of the oxides of nitrogen. If a HCLD is used it shall be kept at a temperature of 328 K to 473 K (55 °C to 200 °C).
              C Converter