CFR > Title 40 - Protection of Environment > CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY > SUBCHAPTER C—AIR PROGRAMS (Parts 50–99) > PART 86—CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES > SUBPART N—Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty Engines; Gaseous and Particulate Exhaust Test Procedures (§86.1301 to §86.1380-2004) > 86.1342-94—Calculations; exhaust emissions.

86.1342-94—Calculations; exhaust emissions.

Section 86.1342-94 includes text that specifies requirements that differ from § 86.1342-90. Where a paragraph in § 86.1342-90 is identical and applicable to § 86.1342-94, this may be indicated by specifying the corresponding paragraph and the statement “[Reserved]. For guidance see § 86.1342-90.”
(a) introductory text [Reserved]. For guidance see § 86.1342-90.
(a) (1) AWM =Weighted mass emission level (HC, CO, CO2. or NOX) in grams per brake horsepower-hour and, if appropriate, the weighted mass total hydrocarbon equivalent, formaldehyde, or non-methane hydrocarbon emission level in grams per brake horsepower-hour.
(a) (2) through (b)(7) [Reserved]. For guidance see § 86.1342-90.
(b) (8) Non-methane hydrocarbon mass:

Code of Federal Regulations

NMHCmass = Vmix × DensityNMHC × (NMHCconc/1,000,000)
(c) through (d)(1)(i) [Reserved]. For guidance see § 86.1342-90.
(d) (1) DensityHC = Density of hydrocarbons.
(A) For gasoline and the gasoline fraction of methanol-fuel, and may be used for petroleum and the petroleum fraction of methanol diesel fuel if desired; 16.33 g/ft 3 -carbon atom (0.5768 kg/m 3 -carbon atom).
(B) For #1 petroleum diesel fuel; 16.42 g/ft 3 -carbon atom (0.5800 kg/m 3 -carbon atom).
(C) For #2 diesel 16.27 g/ft 3 -carbon atom (0.5746 kg/m 3 -carbon atom). Average carbon to hydrogen ratios of 1:1.85 for gasoline, 1:1.93 for #1 petroleum diesel fuel and 1:1.80 for #2 petroleum diesel fuel are assumed at 68 °F (20 °C) and 760 mm Hg (101.3 kPa) pressure.
(D) For natural gas and liquified petroleum gas-fuel; 1.1771 (12.011 H/C (1.008)) g/ft 3 -carbon atom (0.04157 (12.011 H/C (1.008)) kg/m 3 -carbon atom) where H/C is hydrogen to carbon ratio of the hydrocarbon components of the test fuel, at 68 °F (20 °C) and 760 mm Hg (101.3 kPa) pressure.
(d) (1) through (d)(1)(iv)(A) [Reserved]. For guidance see § 86.1342-90.
(d) (1) (B) For petroleum-fueled, natural gas-fueled and liquified petroleum gas-fueled engines, HCe is the FID measurement.
(d) (1) (C) through (d)(3)(v)(A) [Reserved]. For guidance see § 86.1342-90.
(d) (3) (B) COe = [1 − (0.01 0.005HCR) CO2. − 0.000323R] COem for methanol-fuel, natural gas-fuel and liquified petroleum gas-fuel where HCR is hydrogen to carbon ratio as measured for the fuel used.
Where:
(d) (3) through (d)(5)(iii)(B) [Reserved]. For guidance see § 86.1342-90.
(d) (5) (A) CCH3OHe =Methanol concentration in the dilute exhaust, in ppm.
(B)
(v) (A) CCH3OHd =Methanol concentration in the dilution air, in ppm
(B)
(vi) TEM =Temperature of methanol sample withdrawn from dilute exhaust, °R
(vii) TDM =Temperature of methanol sample withdrawn from dilution air, °R
(viii) PB =Barometric pressure during test, mm Hg.
(ix) VEM =Volume of methanol sample withdrawn from dilute exhaust, ft 3
(x) VDM =Volume of methanol sample withdrawn from dilution air, ft 3
(xi) CS =GC concentration of sample drawn from dilute exhaust
(xii) CD =GC concentration of sample drawn from dilution air
(xiii) AVS =Volume of absorbing reagent (deionized water) in impinger through which methanol sample from dilute exhaust is drawn, ml
(xiv) AVD =Volume of absorbing reagent (deionized water) in impinger through which methanol sample from dilution air is drawn, ml
(xv) 1=first impinger.
(xvi) 2=second impinger.
(d) (6) through (d)(7)(i) [Reserved]. For guidance see § 86.1342-90.
(d) (7) For methanol-fueled vehicles, where fuel composition is CX Hy Oz as measured, or calculated, for the fuel used:
(d) (8) [Reserved]. For guidance see § 86.1342-90.
(d) (8) For Otto-cycle engines: KH =1/[1-0.0047(H-75)] (or for SI units, KH =1/[1-0.0329(H-10.71)]).
(iii) For diesel engines: KH = 1/[1-0.0026 (H-75)] (or for SI units = 1/[1-0.0182 (H-10.71)]).
Where:
(d) (8) through (d)(9)(x) [Reserved]. For guidance see § 86.1342-90.
(d) (10) NMHCconc = HCconc -CH4conc
(ii) DensityNMHC = The density of non-methane hydrocarbon, is 1.1771(12.011 H/C (1.008)) g/ft 3 -carbon atom (0.04157(12.011 H/C (1.008))kg/m 3 -carbon atom), where H/C is the hydrogen to carbon ratio of the non-methane hydrocarbon components of the test fuel, at 68 °F (20 °C) and 760 mm Hg (101.3 kPa) pressure.
(iii) (A) CH4conc = Methane concentration of the dilute exhaust sample corrected for background, in ppm carbon equivalent.
(B) CH4conc = rCH4 × (CH4e -CH4d (1-1/DF))
Where:
(1) CH4e = Methane exhaust bag concentration in ppm carbon equivalent.
(2) CH4d = Methane concentration of the dilution air in ppm carbon equivalent.
(3) rCH4 = HC FID response to methane for natural gas-fueled vehicles as measured in § 86.1321 (d).
(e) Through (i) [Reserved]. For guidance see § 86.1342-90.

Code of Federal Regulations

[59 FR 48534, Sept. 21, 1994, as amended at 60 FR 34375, June 30, 1995; 62 FR 47135, Sept. 5, 1997]