(a) Equipment. (1) The sampling and analytical system shall meet the specifications in § 86.107-98(a) through (i).

(2) The refueling equipment nozzle specifications shall meet the requirements described in § 80.32.

(b) General requirements. (1) The refueling test procedure for light-duty liquefied petroleum gas-fueled vehicles and trucks starts with the preconditioning of the vehicle followed by a refueling emissions measurement. The test is conducted by following paragraphs (c) through (f) of this section in order.

(2) Ambient temperature levels encountered by the test vehicle throughout the test sequence shall not be less than 68 °F (20 °C) nor more than 86 °F (30 °C).

(3) The vehicle shall be approximately level during all phases of the test sequence to prevent abnormal fuel distribution.

(c) Vehicle preconditioning. (1) The vehicle fuel tanks are to be filled with fuel that meets the specifications in § 86.113. Fuel tanks shall be filled to 10 percent of nominal fuel tank capacity, determined to the nearest one-tenth of a U.S. gallon (0.38 liter).

(2) The vehicle shall be parked (without starting the engine) within the temperature range specified in paragraph (a)(2) of this section for a minimum of one hour and a maximum of six hours.

(d) Measurement procedure. (1) The steps prior to the actual refueling event described in § 86.154-98(b) through (e)(5) shall be performed.

(2) Within one minute of obtaining the initial FID (or HFID) reading, the dispensed fuel nozzle shall be attached to the vehicle fuel receptacle, and the refueling operation shall be started. If the vehicle is equipped with a fixed liquid level gauge or other gauge or valve which could be opened to release fuel or fuel vapor during refueling, and has not received an exemption as outlined in § 86.098-28(h), § 86.001-28(h) or § 86.004-28(h), the fixed level gauge or other gauges or valves shall be opened after the dispensing nozzle is attached, but prior to the start of the refueling operation. The dispensed fuel must be at a temperature stabilized to approximately the same temperature as the vehicle was in paragraph (c)(2) of this section. The dispensing rate must be typical of in-use dispensing rates for liquefied petroleum gas into light-duty vehicles and trucks.

(3) The fuel flow shall continue until the amount of fuel dispensed is at least 85 percent of nominal fuel tank capacity, determined to the nearest one-tenth of a U.S. gallon (0.38 liter).

(4) Following the fuel shut-off the fixed liquid level gauge or other gauges or valves, if open, shall be closed and the nozzle disconnected.

(5) The final reading of the evaporative enclosure FID (or HFID) analyzer shall be taken 60 ±5 seconds following the disconnect of the refueling nozzle. This is the final hydrocarbon concentration, CHCf, required in § 86.143. The elapsed time, in minutes, between the initial and final FID (or HFID) readings shall be recorded.

(6) For vehicles equipped with more than one fuel tank, the procedures described in this section shall be performed for each fuel tank.

(e) Records required. (1) Test: test number, system or device tested (brief description), date and time of day, instrument operated, operator, enclosure barometric pressure and temperature, recorder charts (identify zero, span, and enclosure gas traces), fuel dispensing rate(s) and dispensed fuel volume.

(2) Vehicle: ID number, manufacturer, model year, engine family, evaporative/refueling emission family, fuel tank(s) capacity, basic fuel system description and odometer reading.

(3) All pertinent instrument information including nozzle and fuel delivery system description. As an alternative, a reference to a vehicle test cell number may be used, with advance approval of the Administrator, provided test cell calibration records show the pertinent instrument information.

(4) All additional information necessary for the calculations specified in paragraph (f) of this section.

(f) Calculations. (1) The calculation of the net hydrocarbon mass change in the enclosure is used to determine refueling mass emissions. The mass is calculated from initial and final hydrocarbon concentrations in ppm carbon, initial and final enclosure ambient temperatures, initial and final barometric pressures and net volume using the equations of § 86.143. For vehicles with multiple tanks, the results for each tank shall be calculated and then summed to determine overall refueling emissions.

(2) The final results for comparison with the refueling control emission standard shall be computed by dividing the total refueling mass emissions by the total gallons of fuel dispensed in the refueling test (see paragraph (d)(3) of this section).

(3) The results of all emission tests shall be rounded, in accordance with ASTM E 29-67 to the number of decimal places contained in the applicable emission standard expressed to one additional significant figure. This procedure has been incorporated by reference (see § 86.1).