Document ID: chunk:federal_register_of_legislation:F2008C00323:reg:3:p13
Version: federal_register_of_legislation:F2008C00323
Segment Type: reg
Provision Reference: reg 3 (pt 13/18)
Character Range: 334237–337205

7.2.3.  The pressure shall be allowed to stabilise prior to isolating the fuel system from the pressure source.

          7.2.4.  Following isolation of the fuel system, the pressure shall not drop by more than
          50 mm of H2O in five minutes.

          7.3. Test for venting

          7.3.1. Vents to the atmosphere from the emission control shall be isolated.

          7.3.2.  A pressure of 370  10 mm of H2O shall be applied to the fuel system.

          7.3.3.  The pressure shall be allowed to stabilise prior to isolating the fuel system from the pressure source.

          7.3.4.  The venting outlets from the emission control systems to the atmosphere shall be reinstated to the production condition.

          7.3.5.  The pressure of the fuel system shall drop to below 100 mm of H20 in not less than 30 seconds but within two minutes.

          7.3.6.  At the request of the manufacturer the functional capacity for venting can be demonstrated by equivalent alternative procedure. The specific procedure should be demonstrated by the manufacturer to the technical service during the type approval procedure.

          7.4.  Purge test

          7.4.1. Equipment capable of detecting an airflow rate of 1.0 litres in one minute shall be attached to the purge inlet and a pressure vessel of sufficient size to have negligible effect on the purge system shall be connected via a switching valve to the purge inlet, or alternatively.

          7.4.2.  The manufacturer may use a flowmeter of his own choosing, if acceptable to the competent authority.

          7.4.3.  The vehicle shall be operated in such a manner that any design feature of the purge system that could restrict purge operation is detected and the circumstances noted.

          7.4.4.  Whilst the engine is operating within the bounds noted in paragraph 7.4.3. above, the air flow shall be determined by either:

          7.4.4.1.  the device indicated in paragraph 7.4.1. above being switched in. A pressure drop from atmospheric to a level indicating that a volume of 1.0 litres of air has flowed into the evaporative emission control system within one minute shall be observed; or

          7.4.4.2. if an alternative flow measuring device is used, a reading of no less than 1.0 litre per minute shall be detectable.

          7.4.4.3.  At the request of the manufacturer an alternative purge tat procedure can be used, if the procedure has been presented to and has been accepted by the technical service during the type approval procedure.

          7.5.  The competent authority which has granted type approval may at any time verify the conformity control methods applicable to each production unit.

          7.5.1. The inspector shall take a sufficiently large sample from the series.

          7.5.2.  The inspector may test these vehicles by application of paragraph 8.2.5. of this Regulation.

          7.6. If the requirements of paragraph 7.5. above