Document ID: chunk:federal_register_of_legislation:F2011C00805:reg:20:p18
Version: federal_register_of_legislation:F2011C00805
Segment Type: reg
Provision Reference: reg 20 (pt 18/23)
Character Range: 192789–195890

is dynamic and suitable for the high flow-rate encountered in constant volume sampler testing. The device shall be of certified accuracy traceable to an approved national or international standard.

           4.5.  Gases

           4.5.1. Pure gases

           The following pure gases shall be available, if necessary, for calibration and operation:

           purified nitrogen:
           (purity:  1 ppm C,  1 ppm CO,  400 ppm CO2,  0.1 ppm NO);

           purified synthetic air:
           (purity:  1 ppm C,  1 ppm CO,  400 ppm CO2,  0.1 ppm NO); oxygen content between 18 and 21 per cent volume;

           purified oxygen: (purity > 99.5 per cent vol. O2);

           purified hydrogen (and mixture containing helium):
           (purity  1 ppm C,   400 ppm CO2);

           carbon monoxide: (minimum purity 99.5 per cent);

           propane: (minimum purity 99.5 per cent).

           4.5.2.  Calibration and span gases

           Mixtures of gases having the following chemical compositions shall be available:

             C8 H8 and purified synthetic air (see paragraph 4.5.1. of this Annex);

             CO and purified nitrogen;

             CO2 and purified nitrogen;

             NO and purified nitrogen.  (The amount of NO2 contained in this calibration gas shall not exceed 5 per cent of the NO content.)

           The true concentration of a calibration gas shall be within  2 per cent of the stated figure.

           The concentrations specified in Appendix 6 to this Annex may also be obtained by means of a gas divider, diluting with purified N2 or with purified synthetic air. The accuracy of the mixing device shall be such that the concentrations of the diluted calibration gases may be determined to within  2 per cent.

           4.6. Additional equipment

           4.6.1.  Temperatures

           The temperatures indicated in Appendix 8 shall be measured with an accuracy of  1.5 K.

           4.6.2.  Pressure

           The atmospheric pressure shall be measurable to within  0.1 kPa.

           4.6.3.  Absolute humidity

           The absolute humidity (H) shall be measurable to within  5 per cent.

           4.7. The exhaust gas-sampling system shall be verified by the method described in paragraph 3. of  Appendix 7 to this Annex.
           The maximum permissible deviation between the quantity of gas introduced and the quantity of gas measured is 5 per cent.

           5.  PREPARING THE TEST

           5.1. Adjustment of inertia simulators to the vehicle's translatory
           inertias

           An inertia simulator shall be used enabling a total inertia of the rotating masses to be obtained proportional to the reference mass within the following limits:

Reference mass of vehicle  Equivalent inertia
RW(kg)                     I(kg)

      RW  480             455

480 < RW  540             510

540 < RW  595             570

595 < RW  650             625

650 < RW  710             680

710 < RW  765             740

765 < RW  850             800

850 < RW  965             910

965 <