P.1 

OAR Box 1856 

Prepped by Keeia Richards 

Document Number: 

73) ll-A-10 

Docket Number: 

A-87-11 

Printed 11/24/2008 12:41:50 PM Sheet 73 of 82 
P.2 

* 

-J7-H I-A 

Id 

DRAFT 

Subpart C 

Emission Regulations for 19XX and Later Model Year New 

or In-Use Light-Duty Vehicles and New or In-Use 

Light-Duty Trucks; Refueling Emissions Test Procedure. 

July 1985 
P.3 

* 

Subpart C - Emission Regulations for 19XX and Later Model 

Year New or In-Use Light-Duty Vehicles and New or In-Use 

Light-Duty Trucks; Refueling Emissions Test Procedure. 

§86.201 General applicability. 

(a) The provisions of this subpart are applicable to 

19XX and later model year new light-duty vehicles and 

light-duty trucks, and to 19XX and later model year 

light-duty vehicles and light-duty trucks in actual use. 

'(b) Provisions of this subpart apply to tests 

performed by both the Administrator and motor vehicle 

manufacturers. 

(c) The procedure of this subpart is intended to be 

performed in conjunction with the exhaust and evaporative 

emissions tests of Subpart B. The following sections of 

Subpart B apply equally to this section and will not be 

repeated in this section. 

1. §86.103 Abbreviations. 

2. §86.104 Section numbering; construction. 

3. §86.113-8X Fuel specifications. 

4. §86.117-78 Evaporative emission enclosure 

calibration. 

5. §86.121-82 Hydrocarbon analyzer calibration. 
P.4 

§86.202 Definitions, 

(a) The definitions of Subpart B apply to this 

Subpart. 

(b) Specific terms used in this subpart are defined 

as follows. 

"In-use vehicle" means a light-duty vehicle or 

light-duty truck which is used on the public highways 

by the "ultimate purchaser" as described in Section 

216 of the Clean Air Act, or any subsequent purchaser. 

. ''Integrated" refueling emission control system means a 

system where vapors resulting from refueling are 

stored in a common vapor storage unit with either or 

both the diurnal heating or hot soak emissions of the 

vehicle and purged through a common purge system. 

"Non-integrated" refueling emission control system 

means a system where fuel vapors from refueling are 

stored in a vapor storage unit assigned solely to the 

functions of storing refueling vapors. 

-2-
P.5 

§86.203 [Reserved] 

-3-
P.6 

§86.204 Introduction; structure of subpart. 

(a) This subpart describes the equipment required 

and the procedures to follow in order to perform refueling 

emissions tests on light-duty gasoline-fueled vehicles and 

light-duty gasoline-fueled trucks. Subpart A sets forth 

testing requirements and test intervals necessary to comply 

with EPA certification procedures. 

(b) Two topics are addressed in this subpart. 

§86.207 sets forth specifications and equipment 

requirements; test procedures and data requirements are 

listed (in approximate order of performance) in §§86.227 

through 86.243. 

-4-
P.7 

§86.205 [Reserved] 

§86.206 [Reserved] 

-5-
P.8 

§86.207 Sampling and analytical system. 

(a) Component description. The components used in 

refueling emissions sampling systems are the same 

components used in the evaporative emissions sampling 

systems as described in §86.107, except for the following 

components which are exclusive to refueling testing. 

(1) Refueling equipment. The refueling equipment 

shall consist of a fuel cart with temperature control 

equipment, fuel flow safety switch, service station type 

dispensing pump, meter, hose, and nozzle. Only the hose 

and nozzle are inside the enclosure. The hose shall 

intersect the enclosure wall below the level of the vehicle 

fuel tank filler; the seal at the intersection of the hose 

and the wall shall be gas tight in accordance with 

§86.117. The amount of fuel trapped in the hose and other 

piping outside of the temperature control unit should be 

minimized. The fuel cart must be capable of delivering 

fuel at 88+2°F (31+1°C) and at a flow rate between 8.0 and 

10.0 gal/min (30.3 and 37.9 l/min). 

(2) Tank fuel heating system. The heating system 

for refueling testing must adhere to the description of 

§86.107 (a)(4) with the following temperature 

requirements. The standard temperature for residual fuel 

in the vehicle fuel tank shall be 86°-95°F (30°-35°C), and 

shall also be 2°-5°F (l.l°-2.8°C) greater than the 

temperature of the dispensed fuel during the refueling 

procedure of paragraph §86.233 (k). 
P.9 

(3) Temperature recording system. Strip chart 

recorder(s) or automatic data processor shall be used to 

record enclosure ambient and vehicle fuel tank temperatures 

during the test. The temperature recorder(s) or data 

processor shall record each temperature at least once every 

20 seconds. The recording system shall be capable of 

resolving time to + 15s and be capable of resolving 

temperature to +0.75°F (0.42°C). The temperature recording 

system (recorder and sensor) shall have an accuracy of +3°F 

(1.7°C). Two ambient temperature sensors, connected to 

provide one average output, shall be located in the 

enclosure. These sensors shall be located at the 

approximate vertical centerline of each side wall extending 

4 inches (10 cm) (nominally) into the enclosure at a height 

of 3+0.5 ft (0.9+0.2m). For certification vehicles, the 

vehicle fuel tank temperature sensors shall be located in 

the fuel tank so as to measure the temperature of the 

residual fuel in the tank and the vapor space in the tank. 

The temperature sensing zones of the temperature sensors 

shall not be in contact with the walls of the fuel tank. 

For in-use vehicles, the temperature sensors shall be 

attached to the external wall- of the vehicle fuel tank in a 

manner such that the temperature sensing capability is not 

impaired. Temperature sensors must be located so that they 

will not lie between or near the interface of the fuel tank 

-7-
P.10 

and the heating source. A temperature sensor shall also be 

located in the fuel dispensing nozzle to measure dispensed 

fuel temperature. Manufacturers shall arrange that 

vehicles furnished for testing at Federal certification 

facilities be equipped with iron-constantan Type J 

thermocouples for measurement of fuel tank temperature. 

(4) Mixing blower. An explosion-proof blower of 

100-200 ftVmin (2-6 m3/min) capacity is required for 

mixing the enclosure atmosphere during tests. This blower 

shall be directed toward any spilled fuel . to aid 

evaporation. 

-8-
§86.208 

§86.209 

§86.210 

§86.211 

§86.212 

§86.213 

§86.214 

§86.215 

§86.216 

§86.217 

§86.218 

§86.219 

§86.220 

§86.221 

§86.222 

§86.223 

§86.224 

§86.225 

§86.226 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] 

[Reserved] • 

p.11 

- 9 -
P.12 

§86.227 Test procedure; overview. 

(a) The procedure described in this and subsequent 

sections is used to determine the conformity of vehicles 

with the refueling emissions standards set forth in Subpart 

A for light-duty vehicles and light-duty trucks. 

(b) The refueling emissions test is designed to 

measure hydrocarbon emissions resulting from the 

displacement of fuel tank vapor during vehicle refueling. 

The refueling emissions shall be measured by the enclosure 

technique. The test shall be conducted in two (2) 

portions, in order to test both storage capacity and purge 

capability of the refueling emission control system. 

(c) All emission control systems installed on or 

incorporated in a new motor vehicle shall be functioning 

during all procedures in this subpart except: 1) in cases 

of component malfunction or failure, and 2) during certain 

specified fuel drain and fill operations at which times the 

refueling emission control canister is disconnected. 

Maintenance to correct component malfunction or failure 

shall be authorized in accordance with §86.0XX-25. 

-10-
§86.228 [Reserved] 

§86.229 [Reserved] 

-11-
P.14 

§86.230 Test sequence; general requirements. 

(a) The placement of the refueling emissions 

procedure in the test sequence of §86.130-78 is shown in 

Figure CXX-1. As indicated, the storage capacity portion 

is to be conducted immediately prior to the vehicle 

preconditioning procedures described in §86.132 of Subpart 

B. The purge portion, required only for vehicles with 

non-integrated refueling emissions control systems, is to 

be conducted immediately following the hot soak evaporative 

emission test if such test is required; otherwise, it is to 

be, conducted immediately following the hot transient 

segment of the exhaust emission test. The refueling 

emissions test procedure is subsequently described. 

(b) Ambient temperature levels encountered by the 

test vehicle shall not be less than 68°F (20°C) nor more 

than 86°F (30°C). The vehicle shall be approximately level 

during all phases of the test sequence to prevent abnormal 

fuel distribution. 

-12-
P.15 

§86.231 Vehicle preparation. 

(a) Prepare the fuel tank for recording the 

prescribed fuel and vapor temperatures at the locations 

described in §86.207 (a)(3). 

(b) Provide additional fittings and adapters, as 

required, to accommodate a fuel drain at the lowest point 

possible in the tank(s) as installed on the vehicle. 

In-use vehicles shall be modified, if at all, in a manner 

which causes no permanent alteration of the vehicle. 

(c) Provide valving or other means to allow the 

venting of the refueling vapor line to the atmosphere 

rather than to the refueling canister when required by this 

test procedure. 

-13-
P.16 

§86.232 Vehicle Preconditioning. 

(a) Vehicles which are parked or stored prior to 

entering the test procedure specified in §86.233 shall have 

their gas caps loosened or removed to allow escape of 

gasoline vapors, thus preventing abnormal loading of the 

canister prior to initiation of the capacity test. Care 

must be taken to ensure that water can not enter the fuel 

tank(s) when the vehicle is parked or stored with the gas 

cap(s) either loosened or removed. 

•(b) Immediately prior to the start of the capacity 

portion of the refueling control test, §86.233 (a), 

vehicles shall be prepared for testing as follows: 

(1) The fuel tank(s) of manufacturer-supplied 

certification vehicles shall be drained and filled to 

one-tenth of the nominal tank capacity, for each tank if 

the vehicle is equipped with more than one tank, determined 

to the nearest one-tenth of a U.S. gallon (0.38 liter), 

with the specified test fuel, §86.113-8X. During the 10 

percent fueling, the canister(s) shall be disconnected. 

(2) In-use vehicles shall have the following 

performed. 

-14-
P.17 

(i) The vehicle fuel tank shall be drained and 

fueled to 40 percent of tank capacity to the nearest 

one-tenth of a U.S. gallon (0.38 liter) with the specified 

test fuel, §86.113-8X. Vehicles shall then be driven for 

50 miles according to the Durability Driving Schedule 

contained in Appendix IV of this Part, or equivalent, as 

approved by the Administrator, prior to the start of 

testing as specified in §86.233. If the vehicle is 

equipped with two fuel tanks, the engine fuel supply shall 

be switched from the first tank to the second tank 

approximately at the mid-point of the 50 mile drive. 

(ii) Following the 50 mile drive, the fuel tank(s) of 

the in-use vehicle shall be drained and refilled to 

one-tenth of the nominal tank capacity, determined to the 

nearest one-tenth of a U.S. gallon (0.38 liter), with the 

specified test fuel, §86.113-8X. During the 10 percent 

fueling, the canister(s) shall be disconnected. 

-15-
§86.233 Refueling Control test. 

(a) The evaporative emission enclosure shall be 

purged for several minutes immediately prior to the test. 

NOTE: If at any time the hydrocarbon concentration 

exceeds 15,000 ppm C the enclosure should be 

immediately purged. This concentration provides a 4:1 

safety factor against the lean flammability limit. 

(b) The FID hydrocarbon analyzer, and additional 

analyzer, if needed, shall be zeroed and spanned 

immediately prior to the test. 

(c) If not already on, the enclosure mixing fan 

shall be turned on at this time. 

(d) The capacity portion of the refueling control 

test shall be performed immediately prior to the vehicle 

preconditioning procedures described in §86.132 of Subpart 

B. The capacity portion of the refueling test shall be 

performed as follows: 

•16-
P.19 

(1) The test vehicle, with the engine shut off, 

shall be moved into the enclosure. The test vehicle 

windows and luggage compartment shall be opened. The 

temperature sensors shall be connected to the temperature 

recording system and the heat source shall be properly 

positioned with respect to the fuel tank(s) and connected 

to the temperature controller. 

(2) The temperature recording system shall be 

started. 

(3) The vehicle fuel tank liquid temperature shall 

be' brought to test temperature, as described in 

§86.207(a)(2), and maintained at that level until the 

beginning of the procedure of paragraph (d)(6) of this 

section. The vapor temperature shall be allowed to rise to 

within +3°F (+1.7°C) of the liquid temperature, and shall 

remain within such a range for a minimum of 10 minutes 

prior to the start of the procedure of paragraph (d)(6) of 

this section. 

(4) An electrical ground shall be attached to the 

vehicle. The refueling nozzle shall be fully inserted into 

the filler neck and the safety switch outside of the 

enclosure shall be in the off position. The enclosure door 

shall be closed and sealed. The FID trace shall be allowed 

to stabilize. 

-17-
P.20 

(5) The initial reading of the evaporative enclosure 

FID analyzer shall be taken immediately prior to the start 

of fuel flow. 

(6) Within one minute of obtaining the initial 

reading of the evaporative enclosure FID analyzer, the 

refueling operation shall be started. The refueling 

operation shall be performed by turning the safety switch 

on and activating the fuel dispensing nozzle. The fuel 

shall be dispensed at 88°+2°F (31°+1°C) and at a dispensing 

rate of between 8.0 and 10.0 gal/min (30.3 and 37.9 

l/min). The fuel flow shall continue until the refueling 

nozzle automatic shut-off is activated. The amount of fuel 

dispensed must be at least 85 percent of fuel tank volume, 

determined to the nearest one-tenth of a U.S. gallon (0.38 

liter). 

(7) The final reading of the evaporative enclosure 

FID analyzer shall be taken 60+5 seconds following the 

shut-off of the fuel flow. The elapsed time, in minutes, 

between the initial and final FID readings shall be 

recorded. 

-18-
P.21 

(8) For vehicles equipped with more than one fuel 

tank, the procedures described in paragraphs (d)(1) through 

(d)(7) above shall be performed for each fuel tank. 

(e) The canister saturation portion of the refueling 

control test shall be performed immediately following the 

capacity portion of the refueling tests as described in 

paragraph (d) above. The canister saturation portion of 

the refueling test shall be performed as follows: 

(1) With the evaporative enclosure door open, the 

vehicle fuel tank(s) shall be drained. The vehicle may be 

removed from the enclosure to facilitate draining of the 

fuel. The vehicle fuel tank shall then be recharged with 

the specific test fuel, §86.113-8X, until automatic 

shut-off of the fuel flow occurs. The enclosure mixing and 

purge blowers may remain on during draining of the fuel 

tank but the purge blowers shall be turned off during 

refueling and the enclosure sealed to allow hydrocarbon 

measurement. 

(2) The procedure of paragraph (e)(1) shall be 

repeated until a sharp rise occurs in the reading of the 

FID analyzer. At this time, the fuel flow shall be 

-19-
P.22 

manually shut off. A sharp rise in the hydrocarbon 

analyzer reading is defined as an increase in hydrocarbon 

concentration by a factor of at least 3 in a one minute 

period. 

(3) For vehicles equipped with multiple fuel tanks 

having separate refueling emissions control canisters for 

each fuel tank, the procedures described in paragraphs 

(e)(1) and (e)(2) shall be performed for each fuel tank. 

(f) The temperature sensors shall be disconnected 

from' the temperature recording system, the test vehicle 

windows and luggage compartments may be closed, and the 

test vehicle, with the engine shut off, shall be removed 

from the enclosure. 

(g) Immediately following the refueling emissions 

capacity test and canister saturation, the vehicle 

preconditioning shall be performed according to §86.132 of 

Subpart B with the exception that the refueling control 

canister shall be disconnected during the fuel drain and 

fill. If desired, the 40 percent tank fuel volume required 

may be attained by adjusting the fuel level in the tank 

following canister saturation rather than by draining and 

refueling. 

-20-
P.23 

(h) Following vehicle preconditioning as specified 

in §86.132, the diurnal breathing loss test shall be 

performed as specified in §86.133 with the exception that 

during the drain -and 40 percent fueling the emission 

control canister shall be disconnected. In addition, 

additional preconditioning as described in §86.132 (a)(3) 

shall not be allowed. 

(i) The running loss, cold and hot start exhaust, 

and evaporative emissions tests shall be performed as 

necessary according to §§86.134 through 86.138. 

(j) The canister purge portion of the refueling 

control test is required to be performed on vehicles 

equipped with non-integrated refueling emission control 

systems. The canister purge portion of the refueling 

control test shall be performed immediately following the 

hot soak evaporative emission test, §86.138, if such test 

is required, or immediately following the hot transient 

exhaust emission test otherwise. 

(1) If the hot soak evaporative emission test is 

required, the vehicle shall be placed, by being pushed, on 

a dynamometer within one hour after the completion of the 

hot soak evaporative emission test. 

-21-
(2) The vehicle exhaust system shall be connected 

either to a CVS or to an exhaust collection system which 

discharges outside of the dynamometer test cell. During 

operation on the dynamometer, road load power setting shall 

be as specified in §86.129, and an auxiliary cooling fan as 

specified in §86.132 (b) shall be used. In addition, 

auxiliary cooling fans may be located so as to provide 

cooling for the vehicle tires and brakes which are in use 

when the vehicle is in operation on the chassis dynamometer. 

(3) The vehicle shall be operated through one Urban 

Dynamometer Driving Schedule (UDDS) test procedure, 

described in §86.115-78 and contained in Appendix I. 

Following completion of the UDDS, the vehicle shall be hot 

soaked for 60+1 minutes with the cooling fans turned off, 

the engine compartment cover closed, and the CVS either 

turned off or the exhaust collection system disconnected 

from the tailpipe(s) of the vehicle. 

(4) The preceding paragraph, (j)(3), shall be 

repeated until approximately 30 percent of the tank fuel 

volume has been used. The number of repetitions shall be 

calculated according to the following equation: 

(FE x 0.3V ) - 11.1 

R = T 

7.5 

-22-
P.25 

Where: 

R = number of repetitions rounded upward 

to the.nearest whole number 

FE = EPA estimated fuel economy of the test 

vehicle on the UDDS, miles per gallon 

VT = nominal fuel tank volume, gallons 

The vehicle may be driven off the dynamometer and out of 

the dynamometer test cell at minimum throttle, the engine 

shut off, and the vehicle pushed to an overnight parking 

site, if necessary, between repetitions of the UDDS. In 

this- case, the vehicle gas cap shall be loosened during the 

time the vehicle is not operating. 

(5) If the vehicle is equipped with more than one 

fuel tank, paragraphs (j)(2) through (j)(4) of this section 

shall be conducted for each fuel tank. 

(6) A refueling test as contained in paragraph (d) 

of this section shall then be conducted with the exception 

that the amount of fuel dispensed shall not be as in 

paragraph (d)(6). The amount of fuel dispensed shall be 

the amount of fuel calculated to have been used in the 

previous procedures: 

V (7.5 R + 11.1 ) 

F = 

FE 

-23-
P.26 

Where: 

VF = fuel volume dispensed, to the 

nearest one-tenth of a U.S. gallon 

(0.38 liter) 

R = number of repetitions conducted in 

accordance with paragraph (j)(4) above 

FE = EPA estimated fuel economy of the 

test vehicle on the UDDS, miles per 

gallon 

(7) The temperature sensors shall be disconnected from the 

temperature recording system, the test vehicle windows and 

luggage compartments may be closed, and the test vehicle, 

with the engine shut off, shall be removed from the 

enclosure. 

-24-
P.27 

§86.234 [Reserved] 

§86.235 [Reserved] 

§86.236 [Reserved] 

§86.237 [Reserved] 

§86.238 [Reserved] 

§86.239 [Reserved] 

§86.240 [Reserved] 

§86.241 [Reserved] 

-25-
P.28 

§86.242 Records required. 

The following information shall be recorded with 

respect to each test: 

(a) Test number. 

(b) System or device tested (brief description). 

(c) Date and time of day. 

•(d) Instrument operated. 

(e) Operator. 

(f) Vehicle: ID number, manufacturer, model year, 

engine family, fuel system (including number of 

carburetors, number of carburetor barrels, fuel injection 

type, and fuel tank(s)- capacity and location), basic engine 

description (including displacement, number of cylinders, 

turbocharger (if used), and catalyst usage), engine code, 

odometer reading. 

(g) All pertinent instrument information including 

nozzle and fuel cart 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. 

-26-
P.29 

(h) Recorder charts: Identify zero, span, and 

sample traces. 

(i) Enclosure barometric pressure and ambient 

temperature. 

NOTE: A central laboratory barometer may be used, 

provided that individual test cell barometric pressures are 

shown to be within +0.1 percent of the barometric pressure 

at the central barometer location. 

. -(j) Temperatures: vehicle fuel tank, both liquid 

and vapor, sufficient to verify required test conditions; 

dispensed fuel, initial and final. 

(k) Fuel dispensing rate. 

(1) All additional information necessary for the 

calculations specified- in §86.243. 

-27-
P.30 

§86.243 Calculations. 

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 enclosure volume using the 

evaporative emissions equation of §86.143-78, with the 

hydrogen-carbon ratio equal to that of diurnal emissions. 

For vehicles with multiple tanks, the results for each tank 

shall be calculated and then summed to determine overall 

refueling emissions. 

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 

dispensed fuel in the refueling test. 

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. 

-28-
P.31 

For vehicles with non-integrated refueling emission 

control systems, results from the refueling capacity 

portion of the test, §86.233 (d), and from the canister 

purge portion of the test, §86.233 (j)(6), shall be 

computed separately. The results from each portion of the 

test must comply with the emission standard. 

-29-