Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:9:p28
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 9 (pt 28/37)
Character Range: 1856564–1859481

shall be available containing mixtures of propane (C3H8) and purified synthetic air. The true concentrations of a calibration gas shall be within 2 per cent of the stated figures. The accuracy of the diluted gases obtained when using a gas divider shall be to within 2 per cent of the true value. The concentrations specified in paragraphs 4.2.3. and 4.3.3. of this annex may also be obtained by the use of a gas divider using synthetic air as the dilutant gas.
              4.8. Carbon canister weighing scale for depressurisation puff loss overflow measurement
               The carbon canister weighing scale shall have an accuracy of ±0.02 g.
              4.9. Fuel tank heating (only applicable for gasoline canister load option)

              4.9.1. The fuel in the vehicle tank(s) shall be heated by a controllable source of heat; for example a heating pad of 2,000 W capacity is suitable. The heating system shall apply heat evenly to the tank walls beneath the level of the fuel so as not to cause local overheating of the fuel. Heat shall not be applied to the vapour in the tank above the fuel.

              4.9.2. The tank heating device shall make it possible to heat the fuel in the tank evenly by 14 °C from 16 °C within 60 minutes, with the temperature sensor position as in paragraph 4.9.3. of this annex. The heating system shall be capable of controlling the fuel temperature to 1.5 °C of the required temperature during the tank heating process.

              4.9.3. The fuel tank of the vehicle shall, without introducing any leaks, be equipped with a temperature sensor to enable the temperature to be measured at the mid-point of the fuel in the fuel tank when filled to 40 per cent of its capacity.

              5. Procedure for carbon canister bench ageing and PF determination
              5.1. Carbon canister bench ageing
              Before performing the hot soak and diurnal losses sequences, the carbon canister shall be aged according to the procedure described in Figure C3/1.
Figure C3/1
              Carbon canister bench ageing procedure

              5.1.1. Ageing through exposure to temperature cycling
              The carbon canister shall be cycled between temperatures from -15 °C to 60 °C in a dedicated temperature enclosure with 30 minutes of stabilisation at -15 °C and 60 °C. Each cycle shall last 210 minutes (see Figure C3/2).
              The temperature gradient shall be as close as possible to 1 °C/min. No forced air flow should pass through the carbon canister.
              The cycle shall be repeated 50 times consecutively. In total, this procedure lasts 175 hours.
    Figure C3/2
Temperature conditioning cycle
              5.1.2. Ageing through exposure to vibration
              Following the temperature ageing procedure, the carbon canister shall be shaken vertically with the carbon canister mounted as per its orientation in the