CFR > Title 40 - Protection of Environment > CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY > SUBCHAPTER C—AIR PROGRAMS (Parts 50–99) > PART 80—REGULATION OF FUELS AND FUEL ADDITIVES > SUBPART D—Reformulated Gasoline (§80.40 to §80.85-80.89) > 80.45—Complex emissions model.

80.45—Complex emissions model.

(a) Definition of terms. For the purposes of this section, the following definitions shall apply:
Target fuel = The fuel which is being evaluated for its emissions performance using the complex model
OXY = Oxygen content of the target fuel in terms of weight percent
SUL = Sulfur content of the target fuel in terms of parts per million by weight
RVP = Reid Vapor Pressure of the target fuel in terms of pounds per square inch
E200 = 200 °F distillation fraction of the target fuel in terms of volume percent
E300 = 300 °F distillation fraction of the target fuel in terms of volume percent
ARO = Aromatics content of the target fuel in terms of volume percent
BEN = Benzene content of the target fuel in terms of volume percent
OLE = Olefins content of the target fuel in terms of volume percent
MTB = Methyl tertiary butyl ether content of the target fuel in terms of weight percent oxygen
ETB = Ethyl tertiary butyl ether content of the target fuel in terms of weight percent oxygen
TAM = Tertiary amyl methyl ether content of the target fuel in terms of weight percent oxygen
ETH = Ethanol content of the target fuel in terms of weight percent oxygen
exp = The function that raises the number e (the base of the natural logarithm) to the power in its domain
Phase I = The years 1995-1999
Phase II = Year 2000 and beyond
(b) Weightings and baselines for the complex model. (1) The weightings for normal and higher emitters (w1 and w2, respectively) given in table 1 shall be used to calculate the exhaust emission performance of any fuel for the appropriate pollutant and Phase:
Table 1—Normal and Higher Emitter Weightings for Exhaust Emissions
Phase I Phase II
VOC & toxics NOX VOC & toxics NOX
Normal Emitters (w1) 0.52 0.82 0.444 0.738
Higher Emitters (w2) 0.48 0.18 0.556 0.262
(2) The following properties of the baseline fuels shall be used when determining baseline mass emissions of the various pollutants:
Table 2—Summer and Winter Baseline Fuel Properties
Fuel property Summer Winter
Oxygen (wt %) 0.0 0.0
Sulfur (ppm) 339 338
RVP (psi) 8.7 11.5
E200 (%) 41.0 50.0
E300 (%) 83.0 83.0
Aromatics (vol %) 32.0 26.4
Olefins (vol %) 9.2 11.9
Benzene (vol %) 1.53 1.64
(3) The baseline mass emissions for VOC, NOX and toxics given in tables 3, 4 and 5 of this paragraph (b)(3) shall be used in conjunction with the complex model during the appropriate Phase and season:
Table 3—Baseline Exhaust Emissions
Exhaust pollutant Phase I Phase II
Summer (mg/mile) Winter (mg/mile) Summer (mg/mile) Winter (mg/mile)
VOC 446.0 660.0 907.0 1341.0
NOX 660.0 750.0 1340.0 1540.0
Benzene 26.10 37.57 53.54 77.62
Acetaldehyde 2.19 3.57 4.44 7.25
Formaldehyde 4.85 7.73 9.70 15.34
1,3-Butadiene 4.31 7.27 9.38 15.84
POM 1.50 2.21 3.04 4.50
Table 4—Baseline Non-Exhaust Emissions (Summer Only)
Non-exhaust pollutant Phase I Phase II
Region 1 (mg/mile) Region 2 (mg/mile) Region 1 (mg/mile) Region 2 (mg/mile)
VOC 860.48 769.10 559.31 492.07
Benzene 9.66 8.63 6.24 5.50
Table 5—Total Baseline VOC, NOX and Toxics Emissions
Pollutant Summer (mg/mile) Phase I Region 1 Region 2 Phase II Region 1 Region 2 Winter (mg/mile) Phase I Region 1 Region 2 Phase II Region 1 Region 2
NOX 660.0 660.0 1340.0 1340.0 750.0 750.0 1540.0 1540.0
VOC 1306.5 1215.1 1466.3 1399.1 660.0 660.0 1341.0 1341.0
Toxics 48.61 47.58 86.34 85.61 58.36 58.36 120.55 120.55
(c) VOC performance. (1) The exhaust VOC emissions performance of gasolines shall be given by the following equations:

Code of Federal Regulations

VOCE = VOC(b) (VOC(b)×Yvoc(t)/100)

Code of Federal Regulations

Yvoc(t) = [(w1×Nv) (w2×Hv)−1]×100
where
VOCE = Exhaust VOC emissions in milligrams/mile
Yvoc(t) = Exhaust VOC performance of the target fuel in terms of percentage change from baseline
VOC(b) = Baseline exhaust VOC emissions as defined in paragraph (b)(2) of this section for the appropriate Phase and season
Nv = [exp v1(t)]/[exp v1(b)]
Hv = [exp v2(t)]/[exp v2(b)]
w1 = Weighting factor for normal emitters as defined in paragraph (b)(1) of this section for the appropriate Phase
w2 = Weighting factor for higher emitters as defined in paragraph (b)(1) of this section for the appropriate Phase
v1(t) = Normal emitter VOC equation as defined in paragraph (c)(1)(i) of this section, evaluated using the target fuel's properties subject to paragraphs (c)(1) (iii) and (iv) of this section
v2(t) = Higher emitter VOC equation as defined in paragraph (c)(1)(ii) of this section, evaluated using the target fuel's properties subject to paragraphs (c)(1) (iii) and (iv) of this section
v1(b) = Normal emitter VOC equation as defined in paragraph (c)(1)(i) of this section, evaluated using the base fuel's properties
v2(b) = Higher emitter VOC equation as defined in paragraph (c)(1)(ii) of this section, evaluated using the base fuel's properties
(i) Consolidated VOC equation for normal emitters.

Code of Federal Regulations

v1 = (−0.003641 × OXY) (0.0005219 × SUL) (0.0289749 × RVP) (−0.014470 × E200) (−0.068624 × E300) (0.0323712 × ARO) (−0.002858 × OLE) (0.0001072 × E2002) (0.0004087 × E3002) (−0.0003481 × ARO × E300)
(ii) VOC equation for higher emitters.

Code of Federal Regulations

v2 = (−0.003626 × OXY) (−5.40×10−5 × SUL) (0.043295 × RVP) (−0.013504 × E200) (−0.062327 × E300) (0.0282042 × ARO) (−0.002858 × OLE) (0.000106 × E2002) (0.000408 × E3002) (−0.000287 × ARO × E300)
(iii) Flat line extrapolations. (A) During Phase I, fuels with E200 values greater than 65.83 percent shall be evaluated with the E200 fuel parameter set equal to 65.83 percent when calculating Yvoc (t) and VOCE using the equations described in paragraphs (c)(1) (i) and (ii) of this section. Fuels with E300 values greater than E300* (calculated using the equation E300* = 80.32 [0.390×ARO]) shall be evaluated with the E300 parameter set equal to E300* when calculating VOCE using the equations described in paragraphs (c)(1) (i) and (ii) of this section. For E300* values greater than 94, the linearly extrapolated model presented in paragraph (c)(1)(iv) of this section shall be used.
(B) During Phase II, fuels with E200 values greater than 65.52 percent shall be evaluated with the E200 fuel parameter set equal to 65.52 percent when calculating VOCE using the equations described in paragraphs (c)(1) (i) and (ii) of this section. Fuels with E300 values greater than E300* (calculated using the equation E300* = 79.75 [0.385 × ARO]) shall be evaluated with the E300 parameter set equal to E300* when calculating VOCE using the equations described in paragraphs (c)(1) (i) and (ii) of this section. For E300* values greater than 94, the linearly extrapolated model presented in paragraph (c)(1)(iv) of this section shall be used.
(iv) Linear extrapolations. (A) The equations in paragraphs (c)(1) (i) and (ii) of this section shall be used within the allowable range of E300, E200, and ARO for the appropriate Phase, as defined in table 6:
Table 6—Allowable Ranges of E200, E300, and ARO for the Exhaust VOC Equations in Paragraphs (c)(1)(i) and (ii) of This Section
Fuel parameter Phase I Phase II
Lower limit Higher limit Lower limit Higher limit
E200 33.00 65.83 33.00 65.52
E300 72.00 Variable 1 72.00 Variable 2
ARO 18.00 46.00 18.00 46.00
1 Higher E300 limit = lower of 94.0 or 80.32 [0.390×(ARO)].
2 Higher E300 limit = lower of 94.0 or 79.75 [0.385×(ARO)].
(B) For fuels with E200, E300 and/or ARO levels outside the ranges defined in table 6, YVOC (t) shall be defined:
(1) For Phase I:

Code of Federal Regulations

YVOC(t) = 100% × 0.52 × [exp(v1(et)) / exp(v1(b)) − 1] 100% × 0.48 × [exp(v2(et)) / exp(v2(b)) − 1] {100% × 0.52 × [exp(v1(et)) / exp(v1(b))] × [{[(0.0002144 × E200et) − 0.014470] × ΔE200} {[(0.0008174 × E300et) − 0.068624 − (0.000348 × AROet)] × ΔE300} {[(−0.000348 × E300et) .0323712] × ΔARO}]} {100% × 0.48 × [exp(v1(et)) / exp(v2(b))}] × [{[(0.000212 × E200et) − 0.01350] × ΔE200} {[(0.000816 × E300et) − 0.06233 − (0.00029 × AROet)] × ΔE300} {[(−0.00029 × E300}) 0.028204] × ΔARO}]}
(2) For Phase II:

Code of Federal Regulations

YVOC(t) = 100% × 0.444 × [exp(v1(et)) / exp(v1(b)) − 1] 100% × 0.556 × [exp(v2(et)) / exp(v2(b)) − 1] {100% × 0.444 × [exp(v1(et)) / exp(v1(b))] × [{[(0.0002144 × E200et) − 0.014470] × ΔE200} {[(0.0008174 × E300et) − 0.068624 − (0.000348 × AROet)] × ΔE300} {[(−0.000348 × E300et) 0.0323712] × ΔARO}]} {100% × 0.556 × [exp(v2(et)) / exp(v2(b))] × [{[(0.000212 × E200et) − 0.01350] × ΔE200} {[(0.000816 × E300et) − 0.06233 − (0.00029 × AROet)] × ΔE300} {[(-0.00029 × E300et) 0.028204] × ΔARO}]}
(C) During Phase I, the “edge target” fuel shall be identical to the target fuel for all fuel parameters, with the following exceptions:
(1) If the E200 level of the target fuel is less than 33 volume percent, then the E200 value for the “edge target” fuel shall be set equal to 33 volume percent.
(2) If the aromatics level of the target fuel is less than 18 volume percent, then the ARO value for the “edge target” fuel shall be set equal to 18 volume percent.
(3) If the aromatics level of the target fuel is greater than 46 volume percent, then the ARO value for the “edge target” fuel shall be set equal to 46 volume percent.
(4) If the E300 level of the target fuel is less than 72 volume percent, then the E300 value for the “edge target” fuel shall be set equal to 72 volume percent.
(5) If the E300 level of the target fuel is greater than 95 volume percent, then the E300 value of the target fuel shall be set equal to 95 volume percent for the purposes of calculating VOC emissions with the Phase I equation given in paragraph (c)(1)(iv)(B) of this section.
(6) If [80.32 (0.390 × ARO)] exceeds 94 for the target fuel, and the target fuel value for E300 exceeds 94, then the E300 value for the “edge target” fuel shall be set equal to 94 volume percent.
(7) If the E200 level of the target fuel is less than 33 volume percent, then ΔE200 shall be set equal to (E200−33 volume percent).
(8) If the E200 level of the target fuel equals or exceeds 33 volume percent, then ΔE200 shall be set equal to zero.
(9) If the aromatics level of the target fuel is less than 18 volume percent, then ΔARO shall be set equal to (ARO−18 volume percent). If the aromatics level of the target fuel is less than 10 volume percent, then ΔARO shall be set equal to −8 volume percent.
(10) If the aromatics level of the target fuel is greater than 46 volume percent, then ΔARO shall be set equal to (ARO−46 volume percent).
(11) If neither of the conditions established in paragraphs (c)(1)(iv)(C)(9) and (10) of this section are met, then ΔARO shall be set equal to zero.
(12) If the E300 level of the target fuel is less than 72 percent, then ΔE300 shall be set equal to (E300−72 percent).
(13) If the E300 level of the target fuel is greater than 94 volume percent and [80.32 (0.390xARO)] also is greater than 94, then ΔE300 shall be set equal to (E300−94 volume percent). If the E300 level of the target fuel is greater than 95 volume percent and [80.32 (0.390×ARO)] also is greater than 94, then ΔE300 shall be set equal to 1 volume percent.
(14) If neither of the conditions established in paragraphs (c)(1)(iv)(C)(12) and (13) of this section are met, then ΔE300 shall be set equal to zero.
(D) During Phase II, the “edge target” fuel is identical to the target fuel for all fuel parameters, with the following exceptions:
(1) If the E200 level of the target fuel is less than 33 volume percent, then the E200 value for the “edge target” fuel shall be set equal to 33 volume percent.
(2) If the aromatics level of the target fuel is less than 18 volume percent, then the ARO value for the “edge target” fuel shall be set equal to 18 volume percent.
(3) If the aromatics level of the target fuel is greater than 46 volume percent, then the ARO value for the “edge target” fuel shall be set equal to 46 volume percent.
(4) If the E300 level of the target fuel is less than 72 volume percent, then the E300 value for the “edge target” fuel shall be set equal to 72 volume percent.
(5) If the E300 level of the target fuel is greater than 95 volume percent, then the E300 value of the target fuel shall be set equal to 95 volume percent for the purposes of calculating VOC emissions with the Phase II equation given in paragraph (c)(1)(iv)(B) of this section.
(6) If [79.75 (0.385 × ARO)] exceeds 94 for the target fuel, and the target fuel value for E300 exceeds 94, then the E300 value for the “edge target” fuel shall be set equal to 94 volume percent.
(7) If the E200 level of the target fuel is less than 33 volume percent, then ΔE200 shall be set equal to (E200−33 volume percent).
(8) If the E200 level of the target fuel equals or exceeds 33 volume percent, then ΔE200 shall be set equal to zero.
(9) If the aromatics level of the target fuel is less than 18 volume percent and greater than or equal to 10 volume percent, then ΔARO shall be set equal to (ARO−18 volume percent). If the aromatics level of the target fuel is less than 10 volume percent, then ΔARO shall be set equal to −8 volume percent.
(10) If the aromatics level of the target fuel is greater than 46 volume percent, then ΔARO shall be set equal to (ARO − 46 volume percent).
(11) If neither of the conditions established in paragraphs (c)(1)(iv)(D)(9) and (10) of this section are met, then ΔARO shall be set equal to zero.
(12) If the E300 level of the target fuel is less than 72 percent, then ΔE300 shall be set equal to (E300 − 72 percent).
(13) If the E300 level of the target fuel is greater than 94 volume percent and (79.75 (0.385 × ARO)) also is greater than 94, then ΔE300 shall be set equal to (E300 − 94 volume percent). If the E300 level of the target fuel is greater than 95 volume percent and (79.75 (0.385 × ARO)) also is greater than 94, then “E300 shall be set equal to 1 volume percent.
(2) The winter exhaust VOC emissions performance of gasolines shall be given by the equations presented in paragraph (c)(1) of this section with the RVP value set to 8.7 psi for both the baseline and target fuels.
(3) The nonexhaust VOC emissions performance of gasolines in VOC Control Region 1 shall be given by the following equations, where:
VOCNE1 = Total nonexhaust emissions of volatile organic compounds in VOC Control Region 1 in grams per mile
VOCDI1 = Diurnal emissions of volatile organic compounds in VOC Control Region 1 in grams per mile
VOCHS1 = Hot soak emissions of volatile organic compounds in VOC Control Region 1 in grams per mile
VOCRL1 = Running loss emissions of volatile organic compounds in VOC Control Region 1 in grams per mile
VOCRF1 = Refueling emissions of volatile organic compounds in VOC Control Region 1 in grams per mile
(i) During Phase I:
VOCNE1 = VOCDI1 VOCHS1 VOCRL1 VOCRF1
VOCDI1 = [0.00736 × (RVP2)] − [0.0790 × RVP] 0.2553
VOCHS1 = [0.01557 × (RVP2)] − [0.1671 × RVP] 0.5399
VOCRL1 = [0.00279 × (RVP2)] [0.1096 × RVP] − 0.7340
VOCRF1 = [0.006668 × RVP] − 0.0180
(ii) During Phase II:
VOCNE1 = VOCDI1 VOCHS1 VOCRL1 VOCRF1
VOCDI1 = [0.007385 × (RVP2)] − [0.08981 × RVP] 0.3158
VOCHS1 = [0.006654 × (RVP2)] − [0.08094 × RVP] 0.2846
VOCRL1 = [0.017768 × (RVP2)] − [0.18746 × RVP] 0.6146
VOCRF1 = [0.004767 × RVP] 0.011859
(4) The nonexhaust VOC emissions performance of gasolines in VOC Control Region 2 shall be given by the following equations, where:
VOCNE2 = Total nonexhaust emissions of volatile organic compounds in VOC Control Region 2 in grams per mile
VOCDI2 = Diurnal emissions of volatile organic compounds in VOC Control Region 2 in grams per mile
VOCHS2 = Hot soak emissions of volatile organic compounds in VOC Control Region 2 in grams per mile
VOCRL2 = Running loss emissions of volatile organic compounds in VOC Control Region 2 in grams per mile
VOCRF2 = Refueling emissions of volatile organic compounds in VOC Control Region 2 in grams per mile
(i) During Phase I:
VOCNE2 = VOCDI2 VOCHS2 VOCRL2 VOCRF2
VOCDI2 = [0.006818 × (RVP2)] − [0.07682 × RVP] 0.2610
VOCHS2 = [0.014421 × (RVP2)] − [0.16248 × RVP] 0.5520
VOCRL2 = [0.016255 × (RVP2)] − [0.1306 × RVP] 0.2963
VOCRF2 = [0.006668 × RVP] − 0.0180
(ii) During Phase II:
VOCNE2 = VOCDI2 VOCHS2 VOCRL2 VOCRF2
VOCDI2 = [0.004775 × (RVP2)] − [0.05872 × RVP] 0.21306
VOCHS2 = [0.006078 × (RVP2)] − [0.07474 × RVP] 0.27117
VOCRL2 = [0.016169 × (RVP2)] − [0.17206 × RVP] 0.56724
VOCRF2 = [0.004767 × RVP] 0.011859
(5) Winter VOC emissions shall be given by VOCE, as defined in paragraph (c)(2) of this section, using the appropriate baseline emissions given in paragraph (b)(3) of this section. Total nonexhaust VOC emissions shall be set equal to zero under winter conditions.
(6) Total VOC emissions. (i) Total summer VOC emissions shall be given by the following equations:
VOCS1 = (VOCE / 1000) VOCNE1
VOCS2 = (VOCE / 1000) VOCNE2
VOCS1 = Total summer VOC emissions in VOC Control Region 1 in terms of grams per mile
VOCS2 = Total summer VOC emissions in VOC Control Region 2 in terms of grams per mile
(ii) Total winter VOC emissions shall be given by the following equations:
VOCW = (VOCE/1000)
VOCW = Total winter VOC emissions in terms of grams per mile
(7) Phase I total VOC emissions performance. (i) The total summer VOC emissions performance of the target fuel in percentage terms from baseline levels shall be given by the following equations during Phase I:
VOCS1% = [100% × (VOCS1−1.306 g/mi)]/(1.306 g/mi)
VOCS2% = [100% × (VOCS2−1.215 g/mi)]/(1.215 g/mi)
VOC1% = Percentage change in VOC emissions from baseline levels in VOC Control Region 1
VOC2% = Percentage change in VOC emissions from baseline levels in VOC Control Region 2
(ii) The total winter VOC emissions performance of the target fuel in percentage terms from baseline levels shall be given by the following equations during Phase I:
VOCW% = [100% × (VOCW−0.660 g/mi)]/(0.660 g/mi)
VOCW% = Percentage change in winter VOC emissions from baseline levels
(8) Phase II total VOC emissions performance. (i) The total summer VOC emissions performance of the target fuel in percentage terms from baseline levels shall be given by the following equations during Phase II:
VOCS1% = [100% × (VOCS1−1.4663 g/mi)]/(1.4663 g/mi)
VOCS2% = [100% × (VOCS2−1.3991 g/mi)]/(1.3991 g/mi)
(ii) The total winter VOC emissions performance of the target fuel in percentage terms from baseline levels shall be given by the following equation during Phase II:
VOCW% = [100% × (VOC −1.341 g/mi)] / (1.341 g/mi)
(d) NO X performance. (1) The summer NOX emissions performance of gasolines shall be given by the following equations:

Code of Federal Regulations

NOX = NOX(b) [NOX(b) × Y(t)/100]

Code of Federal Regulations

YNOX(t) = [(w1 × Nn) (w2 × Hn)−1] × 100
where
NOX = NOX emissions in milligrams/mile
YNOx(t) = NOX performance of target fuel in terms of percentage change from baseline
NOX(b) = Baseline NOX emissions as defined in paragraph (b)(2) of this section for the appropriate phase and season
Nn = exp n1(t)/exp n1(b)
Hn = exp n2(t)/exp n2(b)
w1 = Weighting factor for normal emitters as defined in paragraph (b)(1) of this section for the appropriate Phase
w2 = Weighting factor for higher emitters as defined in paragraph (b)(1) of this section for the appropriate Phase
n1(t) = Normal emitter NOX equation as defined in paragraph (d)(1)(i) of this section, evaluated using the target fuel's properties subject to paragraphs (d)(1)(iii) and (iv) of this section
n2(t) = Higher emitter NOX equation as defined in paragraph (d)(1)(ii) of this section, evaluated using the target fuel's properties subject to paragraphs (d)(1)(iii) and (iv) of this section
n1(b) = Normal emitter NOX equation as defined in paragraph (d)(1)(i) of this section, evaluated using the base fuel's properties
n2(b) = Higher emitter NOX equation as defined in paragraph (d)(1)(ii) of this section, evaluated using the base fuel's properties
(i) Consolidated equation for normal emitters.

Code of Federal Regulations

n1 = (0.0018571 × OXY) (0.0006921 × SUL) (0.0090744 × RVP) (0.0009310 × E200) (0.0008460 × E300) (0.0083632 × ARO) (−0.002774 × OLE) (−6.63×10−7 × SUL2) (−0.000119 × ARO2) (0.0003665 × OLE2)
(ii) Equation for higher emitters.

Code of Federal Regulations

n2 = (−0.00913 × OXY) (0.000252 × SUL) (−0.01397 × RVP) (0.000931 × E200) (−0.00401 × E300) (0.007097 × ARO) (−0.00276 × OLE) (0.0003665 × OLE2) (−7.995×10−5 × ARO2)
(iii) Flat line extrapolations. (A) During Phase I, fuels with olefin levels less than 3.77 volume percent shall be evaluated with the OLE fuel parameter set equal to 3.77 volume percent when calculating NOX performance using the equations described in paragraphs (d)(1)(i) and (ii) of this section. Fuels with aromatics levels greater than 36.2 volume percent shall be evaluated with the ARO fuel parameter set equal to 36.2 volume percent when calculating NOX performance using the equations described in paragraphs (d)(1)(i) and (ii) of this section.
(B) During Phase II, fuels with olefin levels less than 3.77 volume percent shall be evaluated with the OLE fuel parameter set equal to 3.77 volume percent when calculating NOX performance using the equations described in paragraphs (d)(1)(i) and (ii) of this section. Fuels with aromatics levels greater than 36.8 volume percent shall be evaluated with the ARO fuel parameter set equal to 36.8 volume percent when calculating NOX performance using the equations described in paragraphs (d)(1)(i) and (ii) of this section.
(iv) Linear extrapolations. (A) The equations in paragraphs (d)(1)(i) and (ii) of this section shall be used within the allowable range of SUL, OLE, and ARO for the appropriate Phase, as defined in the following table 7:
Table 7—Allowable Ranges of SUL, OLE, and ARO for the NOX Equations in Paragraphs/(d)(1)(i) and (ii) of This Section
Fuel parameter Phase I Phase II
Low end High end Low end High end
SUL 10.0 450.0 10.0 450.0
OLE 3.77 19.0 3.77 19.0
ARO 18.0 36.2 18.0 36.8
(B) For fuels with SUL, OLE, and/or ARO levels outside the ranges defined in Table 7 of paragraph (d)(1)(iv)(A) of this section, YNOx (t) shall be defined as:

Code of Federal Regulations

(1) For Phase I:

Code of Federal Regulations

YNOx(t) = 100% × 0.82 × [exp(n1(et))/exp(n1(b)) − 1]
Code of Federal Regulations 646

Code of Federal Regulations

100% × 0.18 × [exp(n2(et))/exp(n2(b)) − 1]

Code of Federal Regulations

{100% × 0.82 × [exp(n1(et))/exp(n1(b))] × [{[(−0.00000133 × SULet) 0.000692] × ΔSUL}

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{[(−0.000238 × AROet) 0.0083632] × ΔARO}

Code of Federal Regulations

{[(0.000733 × OLEet) − 0.002774] × ΔOLE}]}

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{100% × 0.18 × [exp(n2(et))/exp(n2(b))]
× [{0.000252 × ΔSUL}

Code of Federal Regulations

{[(−0.0001599 × AROet) 0.007097] × ΔARO}

Code of Federal Regulations

{[(0.000732 × OLEet) − 0.00276] × ΔOLE}]}
(2) For Phase II:

Code of Federal Regulations

YNO X(t) = 100% × 0.738 × [exp(n1(et))/exp(n1(b)) − 1]

Code of Federal Regulations

100% × 0.262 × [exp(n2(et)/exp(n2(b)) − 1]

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[100% × 0.738 × [exp(n1(et))/exp(n1(b))]

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× [{[(−0.00000133 × SULet) 0.000692] × ΔSUL}

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{[(−0.000238 × AROet) 0.0083632] × ΔARO}

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{[(0.000733 × OLEet) − 0.002774] × ΔOLE}]}

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{100% × 0.262 × [exp(n2(et))/exp(n2(b))]
× [{0.000252 × ΔSUL}

Code of Federal Regulations

× [{(−0.0001599 × AROet) 0.007097] × ΔARO}

Code of Federal Regulations

{[(0.000732 × OLEet) − 0.00276] × ΔOLE}]}
Where:

Code of Federal Regulations

n1, n2 = The equations defined in paragraphs (d)(1) (i) and (ii) of this section.
et = Collection of fuel parameters for the “edge target” fuel. These parameters are defined in paragraphs (d)(1)(iv) (C) and (D) of this section.

Code of Federal Regulations

n1(et) = The function n1 evaluated with “edge target” fuel parameters, which are defined in paragraph (d)(1)(iv)(C) of this section.

Code of Federal Regulations

n2(et) = The function n2 evaluated with “edge target” fuel parameters, which are defined in paragraph (d)(1)(iv)(C) of this section.

Code of Federal Regulations

n1(b) = The function n1 evaluated with the appropriate baseline fuel parameters defined in paragraph (b)(2) of this section.

Code of Federal Regulations

n2(b) = The function n2 evaluated with the appropriate baseline fuel parameters defined in paragraph (b)(2) of this section.

Code of Federal Regulations

SULet = The value of SUL for the “edge target” fuel, as defined in paragraph (d)(1)(iv)(C) of this section.

Code of Federal Regulations

AROet = The value of ARO for the “edge target” fuel, as defined in paragraph (d)(1)(iv)(C) of this section.

Code of Federal Regulations

OLEet = The value of OLE for the “edge target” fuel, as defined in paragraph (d)(1)(iv)(C) of this section.
(C) For both Phase I and Phase II, the “edge target” fuel is identical to the target fuel for all fuel parameters, with the following exceptions:
(1) If the sulfur level of the target fuel is less than 10 parts per million, then the value of SUL for the “edge target” fuel shall be set equal to 10 parts per million.
(2) If the sulfur level of the target fuel is greater than 450 parts per million, then the value of SUL for the “edge target” fuel shall be set equal to 450 parts per million.
(3) If the aromatics level of the target fuel is less than 18 volume percent, then the value of ARO for the “edge target” fuel shall be set equal to 18 volume percent.
(4) If the olefins level of the target fuel is greater than 19 volume percent, then the value of OLE for the “edge target” fuel shall be set equal to 19 volume percent.
(5) If the E300 level of the target fuel is greater than 95 volume percent, then the E300 value of the target fuel shall be set equal to 95 volume percent for the purposes of calculating NOX emissions with the equations given in paragraph (d)(1)(iv)(B) of this section.
(6) If the sulfur level of the target fuel is less than 10 parts per million, then ΔSUL shall be set equal to (SUL−10 parts per million).
(7) If the sulfur level of the target fuel is greater than 450 parts per million, then ΔSUL shall be set equal to (SUL−450 parts per million).
(8) If the sulfur level of the target fuel is neither less than 10 parts per million nor greater than 450 parts per million, ΔSUL shall be set equal to zero.
(9) If the aromatics level of the target fuel is less than 18 volume percent and greater than 10 volume percent, then ΔARO shall be set equal to (ARO−18 volume percent). If the aromatics level of the target fuel is less than 10 volume percent, then ΔARO shall be set equal to −8 volume percent.
(10) If the aromatics level of the target fuel is greater than or equal to 18 volume percent, then ΔARO shall be set equal to zero.
(11) If the olefins level of the target fuel is greater than 19 volume percent, then ΔOLE shall be set equal to (OLE−19 volume percent).
(12) If the olefins level of the target fuel is less than or equal to 19 volume percent, then ΔOLE shall be set equal to zero.
(2) The winter NOX emissions performance of gasolines shall be given by the equations presented in paragraph (d)(1) of this section with the RVP value set to 8.7 psi.
(3) The NOX emissions performance of the target fuel in percentage terms from baseline levels shall be given by the following equations:
For Phase I:

Code of Federal Regulations

Summer NOX% = [100% × (NOX−0.660 g/mi)]/(0.660 g/mi)

Code of Federal Regulations

Winter NOX% = [100% × (NOX−0.750 g/mi)]/(0.750 g/mi)
For Phase II:

Code of Federal Regulations

Summer NOX% = [100% × (NOX−1.340 g/mi)]/(1.340 g/mi)

Code of Federal Regulations

Winter NOX% = [100% × (NOX−1.540 g/mi)]/(1.540 g/mi)

Code of Federal Regulations

Summer NOX% = Percentage change in NOX emissions from summer baselin