Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:9:p27
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 9 (pt 27/37)
Character Range: 1853742–1856803

in the case of use of the gasoline canister load option (paragraph 6.5.5.3. of this annex).
              4.4.3. Temperatures shall, throughout the evaporative emission measurements, be recorded or entered into a data processing system at a frequency of at least once per minute.
              4.4.4. The accuracy of the temperature recording system shall be within 1.0 K and the temperature shall be capable of being resolved to 0.4 K.
              4.4.5. The recording or data processing system shall be capable of resolving time to 15 seconds.
              4.5. Pressure recording system
              The pressure recording system shall meet the requirements of paragraphs 4.5.1. to 4.5.3.
              4.5.1. The difference Δp between barometric pressure within the test area and the enclosure internal pressure shall, throughout the evaporative emission measurements, be recorded or entered into a data processing system at a frequency of at least once per minute.
              4.5.2. The accuracy of the pressure recording system shall be within 0.3 kPa and the pressure shall be capable of being resolved to 0.025 kPa.
              4.5.3. The recording or data processing system shall be capable of resolving time to 15 seconds.
              4.6. Fans
              The fans shall meet the requirements of paragraphs 4.6.1. and 4.6.2. of this annex.
              4.6.1. By the use of one or more fans or blowers with the Sealed Housing Evaporative Determination (SHED) door(s) open, it shall be possible to reduce the hydrocarbons concentration in the chamber to the ambient hydrocarbon level.
              4.6.2. The chamber shall have one or more fans or blowers of like capacity 0.1 to 0.5 m3/sec. with which to thoroughly mix the atmosphere in the enclosure. It shall be possible to attain an even temperature and hydrocarbon concentration in the chamber during measurements. The vehicle in the enclosure shall not be subjected to a direct stream of air from the fans or blowers.
              4.7. Calibration gases
              The gases shall meet the requirements of paragraphs 4.7.1. and 4.7.2. of this annex.
              4.7.1. The following pure gases shall be available for calibration and operation:
               Purified synthetic air: (purity < 1 ppm C1 equivalent,
               1 ppm CO,  400 ppm CO2,  0.1 ppm NO);
               Oxygen content between 18 and 21 per cent by volume.
               Hydrocarbon analyser fuel gas: (40  2 per cent hydrogen, and balance helium with less than 1 ppm C1 equivalent hydrocarbon, less than 400 ppm CO2),
               Propane (C3H8): 99.5 per cent minimum purity.
               Butane (C4H10): 98 per cent minimum purity.
               Nitrogen (N2): 98 per cent minimum purity.
              4.7.2. Calibration and span gases 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