Skip to main content
 
CFR › Title 40 › Chapter I › Subchapter U › Part 1065 › Subpart G › Section 1065.665

40 CFR 1065.665 - THCE and NMHCE determination.

There is 1 rule appearing in the Federal Register for 40 CFR 1065. Select the tab below to view, or View eCFR (GPOAccess)
§ 1065.665 THCE and NMHCE determination.
(a) If you measured an oxygenated hydrocarbon's mass concentration, first calculate its molar concentration in the exhaust sample stream from which the sample was taken (raw or diluted exhaust), and convert this into a C1-equivalent molar concentration. Add these C1-equivalent molar concentrations to the molar concentration of NOTHC. The result is the molar concentration of THCE. Calculate THCE concentration using the following equations, noting that equation 1065.665-3 is only required if you need to convert your OHC concentration from mass to moles:
Where:
x THCE = The C1-equivalent sum of the concentration of carbon mass contributions of non-oxygenated hydrocarbons, alcohols, and aldehydes.
x NOTHC = The C1-equivalent sum of the concentration of nonoxygenated THC.
x OHC i = The C1-equivalent concentration of oxygenated species i in diluted exhaust, not corrected for initial contamination.
x OHC i -init = The C1-equivalent concentration of the initial system contamination (optional) of oxygenated species i, dry-to-wet corrected.
x THC[THC-FID]cor = The C1-equivalent response to NOTHC and all OHC in diluted exhaust, HC contamination and dry-to-wet corrected, as measured by the THC-FID.
RF OHC i [THC-FID] = The response factor of the FID to species i relative to propane on a C1-equivalent basis.
C # = The mean number of carbon atoms in the particular compound.
M dexh = The molar mass of diluted exhaust as determined in § 1065.340.
m dexhOHC i = The mass of oxygenated species i in dilute exhaust.
M OHC i = The C1-equivalent molecular weight of oxygenated species i.
m dexh = The mass of diluted exhaust.
n dexhOHC i = The number of moles of oxygenated species i in total diluted exhaust flow.
n dexh = The total diluted exhaust flow.
(b) If we require you to determine NMHCE, use the following equation:
Where:
x NMHCE = The C1-equivalent sum of the concentration of carbon mass contributions of non-oxygenated NMHC, alcohols, and aldehydes.
RF CH4[THC-FID] = response factor of THC-FID to CH4.
x CH4 = concentration of CH4, HC contamination (optional) and dry-to-wet corrected, as measured by the gas chromatograph FID.
(c) The following example shows how to determine NMHCE emissions based on ethanol (C2H5OH), methanol (CH3OH), acetaldehyde (C2H4O), and formaldehyde (HCHO) as C1-equivalent molar concentrations:
x THC[THC-FID]cor = 145.6 µmol/mol
x CH4 = 18.9 µmol/mol
x C2H5OH = 100.8 µmol/mol
x CH3OH = 1.1 µmol/mol
x C2H4O = 19.1 µmol/mol
x HCHO = 1.3 µmol/mol
RF CH4[THC-FID] = 1.07
RF C2H5OH[THC-FID] = 0.76
RF CH3OH[THC-FID] = 0.74
RF H2H4O[THC-FID] = 0.50
RF HCHO[THC-FID] = 0.0
x NMHCE = x THC[THC-FID]cor−(x C2H5OH · RF C2H5OH[THC-FID] x CH3OH · RF CH3OH[THC-FID] x C2H4O · RF C2H4O[THC-FID] x HCHO · RF HCHO[THC-FID] x C2H5OH x CH3OH x C2H4O x HCHO−(RF CH4[THC-FID] · x CH4)
x NMHCE = 145.6−(100.8 · 0.76 1.1 · 0.74 19.1 · 0.50 1.3 · 0) 100.8 1.1 19.1 1.3−(1.07 · 18.9)
xNMHCE = 160.71 µmol/mol
[73 FR 37337, June 30, 2008]

Title 40 published on 2012-07-01

The following are only the Rules published in the Federal Register after the published date of Title 40.

For a complete list of all Rules, Proposed Rules, and Notices view the Rulemaking tab.

  • 2012-08-27; vol. 77 # 166 - Monday, August 27, 2012
    1. 77 FR 51701 - EPA's Denial of the Petition To Reconsider the Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles
      GPO FDSys XML | Text
      ENVIRONMENTAL PROTECTION AGENCY
      Denial of petition to reconsider.
      This denial is effective August 27, 2012.
      40 CFR Parts 85, 86, 600, 1033, 1036, 1037, 1039, 1065, 1066, and 1068

This is a list of United States Code sections, Statutes at Large, Public Laws, and Presidential Documents, which provide rulemaking authority for this CFR Part.

This list is taken from the Parallel Table of Authorities and Rules provided by GPO [Government Printing Office].

It is not guaranteed to be accurate or up-to-date, though we do refresh the database weekly. More limitations on accuracy are described at the GPO site.

Title 40 published on 2012-07-01

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 40 CFR 1065 after this date.

  • 2012-08-27; vol. 77 # 166 - Monday, August 27, 2012
    1. 77 FR 51701 - EPA's Denial of the Petition To Reconsider the Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles
      GPO FDSys XML | Text
      ENVIRONMENTAL PROTECTION AGENCY
      Denial of petition to reconsider.
      This denial is effective August 27, 2012.
      40 CFR Parts 85, 86, 600, 1033, 1036, 1037, 1039, 1065, 1066, and 1068