Document ID: chunk:federal_register_of_legislation:F2023L01526:body:0:p53
Version: federal_register_of_legislation:F2023L01526
Segment Type: other
Provision Reference: 
Character Range: 148261–151233

enclosure, in ppm volume

                     V = net enclosure volume in cubic metres (m3) corrected for the volume of the vehicle, with the windows and the luggage compartment open. If the volume of the vehicle is not determined a volume of 1.42 m³ is subtracted.

                     Vout = compensation volume in m³, at the test temperature and pressure

                     T = ambient chamber temperature, in K

                     P = absolute enclosure pressure, in kPa

                     k = 2.42

       Where: i is the initial reading

                     f is the final reading

       6.1. Results of test

        The hydrogen mass emissions for the REESS are:

       MN = hydrogen mass emission for normal charge test, in grams

       MD = hydrogen mass emission for charging failure test, in grams

Annex 8 ‑ Appendix 1

Calibration of equipment for hydrogen emission testing

       1. Calibration frequency and methods

        All equipment shall be calibrated before its initial use and then calibrated as often as necessary and in any case in the month before type approval testing.  The calibration methods to be used are described in this appendix.

       2. Calibration of the enclosure

       2.1. Initial determination of enclosure internal volume

       2.1.1. Before its initial use, the internal volume of the chamber shall be determined as follows. The internal dimensions of the chamber are carefully measured, taking into account any irregularities such as bracing struts. The internal volume of the chamber is determined from these measurements.

       The enclosure shall be latched to a fixed volume when the enclosure is held at an ambient temperature of 293 K. This nominal volume shall be repeatable within ±0.5 per cent of the reported value.

       2.1.2. The net internal volume is determined by subtracting 1.42 m3 from the internal volume of the chamber. Alternatively the volume of the test vehicle with the luggage compartment and windows open or REESS may be used instead of the 1.42 m3.

       2.1.3. The chamber shall be checked as in Annex 8, paragraph 2.3. If the hydrogen mass does not agree with the injected mass to within ±2 per cent then corrective action is required.

       2.2. Determination of chamber background emissions

       This operation determines that the chamber does not contain any materials that emit significant amounts of hydrogen. The check shall be carried out at the enclosure's introduction to service, after any operations in the enclosure which may affect background emissions and at a frequency of at least once per year.

       2.2.1. Variable-volume enclosure may be operated in either latched or unlatched volume configuration, as described in paragraph 2.1.1. above. Ambient temperature shall be maintained at 293 K ± 2 K, throughout the four-hour period mentioned below.

       2.2.2. The enclosure may be sealed and the mixing fan operated for a period of up to 12