40 CFR 86.345-79 - Emission calculations.

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§ 86.345-79 Emission calculations.
(a) The following abbreviations (and units) are used in this section.
α = atomic hydrogen/carbon ratio of the fuel
φ = dry fuel-air ratio (measured)/fuel-air ratio (stoichiometric)
BARO = Barometric pressure (in. H gA)
BHP = Brake horsepower
BSCO = Brake specific carbon monoxide emissions, (gm/BHP-HR)
BSFC = Brake specific fuel consumption (lb/BHP-HR)
BSHC = Brake specific hydrocarbon emissions (gm/BHP-HR)
BSNO X = Brake specific oxides of nitrogen emissions (gm/BHP-HR)
DCO = CO volume concentration in exhaust, ppm (dry)
DCO 2 = CO2 volume concentration in exhaust, percent (dry)
DHC = HC volume carbon concentration in exhaust, ppmC (dry)
DKNO = NO volume concentration in exhaust, in ppm (dry and humidity corrected)
EIP = engine intake pressure (in. H gA) = BARO − inlet depression
f/a = measured dry fuel-air ratio
G = humidity of the inlet air in grains of water per pound of dry air = (453.59/0.0648) H, (see § 86.344)
K = water − gas equilibrium constant = 3.5
K NOx = Humidity correction factor for oxides of nitrogen
K w = Wet to dry correction factor
M C = Atomic weight of carbon
(M C M H) = mean molecular weight of the fuel per carbon atom
M CO = Molecular weight of CO
M F = Mass flow-rate of fuel used in the engine in lb/hr = W f/453.59
M H = Atomic weight of hydrogen
M NO 2 = Molecular weight of nitrogen dioxide (NO2)
T = Temperature of inlet air (°F)
W CO = Mass rate of CO in exhaust, grams/hr
W f = Mass flow-rate of fuel used in the engine, in grams/hr = (453.59)×(W f lbs/hr)
WHC = HC volume concentration in exhaust, ppm C(wet)
W HC = Mass rate of HC in exhaust, grams/hr
W NOx = Mass rate of NOX in exhaust, grams/hr
Y = H2O volume concentration of intake air (See § 86.344)
(b) Determine the exhaust species volume concentration for each mode.
(c)
(1) Convert wet basis measurements to a dry basis by the following:
Dry concentrations = 1/K W×wet concentrations. K W is defined by the equation in Figure D79-6.
(2) For Diesel engines, for each mode use the measured engine (f/a) entering the combustion chamber when calculating φ. If applicable bleed air, etc. must be subtracted from the measured air flow (see § 86.313).
(3) For gasoline-fueled engines, optional for Diesel engines, calculate φ for each mode by substituting WHC for DHC in the (f/a) equations in paragraph (d) of this section.
(4) Calculate a Y value for each gasoline-fueled engine test from the pre-test data. Apply the Y value to the K W equation for the entire test.
(5) Calculate a separate Y value for each Diesel test segment from the pretest-segment data. Apply the Y value to the K W equation for the entire test-segment.
Figure D79-6. K wWet to Dry Correction Factor
(d) Compute the dry (f/a) if required as follows:
Where
(e) Data validation—
(1) Diesel engines only. Compare the calculated dry (f/a) with the measured fuel and air flow. For a valid test the emission calculated (f/a) must agree within 10 percent of the measured (f/a) for each mode. Diesel engine idle and 2 percent modes do not have to meet this requirement.
(2) Fuel/Air ratio comparison. When comparing measured (f/a) ratio to an emissions calculated (f/a) ratio, the measured air flow (in terms of mass) is the total mass of air entering the exhaust pipe. This may include additions of air mass to the exhaust pipe by an air injection system.
(3) Other methods of data validation may be used if prior approval is obtained from the Administrator.
(4) Data validation techniques that have obtained prior approval from the Administrator for use on gasoline-fueled engines may be used to determine void tests.
(f) Multiply the dry nitric oxide volume concentrations by the following humidity correction factor to obtain DKNO:
(1) Gasoline-fueled engines:
K NOx 0.6272 = 0.00629G − 0.0000176G2
(2) Diesel engines:
where:
A = 0.044 (f/a) − 0.0038
B = − 0.116(f/a) 0.0053
T = Temperature of inlet air, °F.
(g) Calculate the mass emissions of each species in grams per hour for each mode as follows:
(h)
(1) For gasoline-fueled engines, weight the mass values of BHIP, W HC , W CO , Mf, and W NOx for each mode by multiplying the modal mass values by the appropriate modal weighting factor prescribed by § 86.335.
(2) For Diesel engines, weight the values of BHP, W HC, W CO, W NOx, and Mf as follows:
(i) Weight the values from each idle mode by multiplying the values by (0.067);
(ii) Weight the remaining modes by multiplying the values by 0.08.
(i) Calculate the brake specific emissions for:
(1) Each gasoline-fueled engine test cycle, and
(2) Each Diesel engine test by summing the weighted values (BHP, W HC, W CO, and W NOx) from each mode as follows:
(t) = Test cycle number (t = 1, 2) (gasoline-fueled engines only).
(j)
(1) Calculate the brake-specific fuel consumption (BSFC) from the nonweighted BHP and Mf for each mode. Gasoline-fueled engine idle and CT modes, and Diesel idle modes are excluded.
(2) For gasoline-fuel engines use:
(3) For Diesel engines use:
where:
(4) Other methods of correcting power to determine BSFC may be used only with prior approval of the Administrator.
(k) Calculate the weighted brake-specific fuel consumption (WBSFC) for
(1) Each gasoline engine test cycle by:
where:
t = Test cycle number (t = 1,2)
(2) Each Diesel engine test by:
(l) For gasoline-fueled engines, calculate the brake-specific emissions and fuel consumption for the complete test as follows:
BSHC(T) = 0.35 BSHC(1) = 0.65 BSHC(2)
BSCO(T) = 0.35 BSCO(1) = 0.65 BSCO(2)
BSNO x(T) = 0.35 BSNO x(1) = 0.65 BSNO x(2)
WBSFC(T) = 0.35 WBSFC(1) = 0.65 WBSFC(2)

Title 40 published on 2013-07-01

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  • 2014-08-08; vol. 79 # 153 - Friday, August 8, 2014
    1. 79 FR 46356 - Emergency Vehicle Rule—SCR Maintenance and Regulatory Flexibility for Nonroad Equipment
      GPO FDSys XML | Text
      ENVIRONMENTAL PROTECTION AGENCY
      Final rule.
      This rule is effective on September 8, 2014.
      40 CFR Parts 86 and 1039

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United States Code
U.S. Code: Title 42 - THE PUBLIC HEALTH AND WELFARE

§ 7401 - Congressional findings and declaration of purpose

§ 7402 - Cooperative activities

§ 7403 - Research, investigation, training, and other activities

§ 7404 - Research relating to fuels and vehicles

§ 7405 - Grants for support of air pollution planning and control programs

§ 7406 - Interstate air quality agencies; program cost limitations

§ 7407 - Air quality control regions

§ 7408 - Air quality criteria and control techniques

§ 7409 - National primary and secondary ambient air quality standards

§ 7410 - State implementation plans for national primary and secondary ambient air quality standards

§ 7411 - Standards of performance for new stationary sources

§ 7412 - Hazardous air pollutants

§ 7413 - Federal enforcement

§ 7414 - Recordkeeping, inspections, monitoring, and entry

§ 7415 - International air pollution

§ 7416 - Retention of State authority

§ 7417 - Advisory committees

§ 7418 - Control of pollution from Federal facilities

§ 7419 - Primary nonferrous smelter orders

§ 7420 - Noncompliance penalty

§ 7421 - Consultation

§ 7422 - Listing of certain unregulated pollutants

§ 7423 - Stack heights

§ 7424 - Assurance of adequacy of State plans

§ 7425 - Measures to prevent economic disruption or unemployment

§ 7426 - Interstate pollution abatement

§ 7427 - Public notification

§ 7428 - State boards

§ 7429 - Solid waste combustion

§ 7430 - Emission factors

§ 7431 - Land use authority

§ 7450 to 7459 - Repealed.

§ 7470 - Congressional declaration of purpose

§ 7471 - Plan requirements

§ 7472 - Initial classifications

§ 7473 - Increments and ceilings

§ 7474 - Area redesignation

§ 7475 - Preconstruction requirements

§ 7476 - Other pollutants

§ 7477 - Enforcement

§ 7478 - Period before plan approval

§ 7479 - Definitions

§ 7491 - Visibility protection for Federal class I areas

§ 7492 - Visibility

§ 7501 - Definitions

§ 7502 - Nonattainment plan provisions in general

§ 7503 - Permit requirements

§ 7504 - Planning procedures

§ 7505 - Environmental Protection Agency grants

§ 7505a - Maintenance plans

§ 7506 - Limitations on certain Federal assistance

§ 7506a - Interstate transport commissions

§ 7507 - New motor vehicle emission standards in nonattainment areas

§ 7508 - Guidance documents

§ 7509 - Sanctions and consequences of failure to attain

§ 7509a - International border areas

§ 7511 - Classifications and attainment dates

§ 7511a - Plan submissions and requirements

§ 7511b - Federal ozone measures

§ 7511c - Control of interstate ozone air pollution

§ 7511d - Enforcement for Severe and Extreme ozone nonattainment areas for failure to attain

§ 7511e - Transitional areas

§ 7511f - NO

§ 7512 - Classification and attainment dates

§ 7512a - Plan submissions and requirements

§ 7513 - Classifications and attainment dates

§ 7513a - Plan provisions and schedules for plan submissions

§ 7513b - Issuance of RACM and BACM guidance

§ 7514 - Plan submission deadlines

§ 7514a - Attainment dates

§ 7515 - General savings clause

§ 7521 - Emission standards for new motor vehicles or new motor vehicle engines

§ 7522 - Prohibited acts

§ 7523 - Actions to restrain violations

§ 7524 - Civil penalties

§ 7525 - Motor vehicle and motor vehicle engine compliance testing and certification

§ 7541 - Compliance by vehicles and engines in actual use

§ 7542 - Information collection

§ 7543 - State standards

§ 7544 - State grants

§ 7545 - Regulation of fuels

§ 7546 - Renewable fuel

§ 7547 - Nonroad engines and vehicles

§ 7548 - Study of particulate emissions from motor vehicles

§ 7549 - High altitude performance adjustments

§ 7550 - Definitions

§ 7551 - Omitted

§ 7552 - Motor vehicle compliance program fees

§ 7553 - Prohibition on production of engines requiring leaded gasoline

§ 7554 - Urban bus standards

§ 7571 - Establishment of standards

§ 7572 - Enforcement of standards

§ 7573 - State standards and controls

§ 7574 - Definitions

§ 7581 - Definitions

§ 7582 - Requirements applicable to clean-fuel vehicles

§ 7583 - Standards for light-duty clean-fuel vehicles

§ 7584 - Administration and enforcement as per California standards

§ 7585 - Standards for heavy-duty clean-fuel vehicles (GVWR above 8,500 up to 26,000 lbs.)

§ 7586 - Centrally fueled fleets

§ 7587 - Vehicle conversions

§ 7588 - Federal agency fleets

§ 7589 - California pilot test program

§ 7590 - General provisions

§ 7601 - Administration

§ 7602 - Definitions

§ 7603 - Emergency powers

§ 7604 - Citizen suits

§ 7605 - Representation in litigation

§ 7606 - Federal procurement

§ 7607 - Administrative proceedings and judicial review

§ 7608 - Mandatory licensing

§ 7609 - Policy review

§ 7610 - Other authority

§ 7611 - Records and audit

§ 7612 - Economic impact analyses

§ 7613 - Repealed.

§ 7614 - Labor standards

§ 7615 - Separability

§ 7616 - Sewage treatment grants

§ 7617 - Economic impact assessment

§ 7618 - Repealed.

§ 7619 - Air quality monitoring

§ 7620 - Standardized air quality modeling

§ 7621 - Employment effects

§ 7622 - Employee protection

§ 7623 - Repealed.

§ 7624 - Cost of vapor recovery equipment

§ 7625 - Vapor recovery for small business marketers of petroleum products

42 U.S. Code § 7450 to 7459 - Repealed.

§ 7625a - Statutory construction

§ 7626 - Authorization of appropriations

§ 7627 - Air pollution from Outer Continental Shelf activities

§ 7628 - Demonstration grant program for local governments

§ 7641 - Noise abatement

§ 7642 - Authorization of appropriations

§ 7651 - Findings and purposes

§ 7651a - Definitions

§ 7651b - Sulfur dioxide allowance program for existing and new units

§ 7651c - Phase I sulfur dioxide requirements

§ 7651d - Phase II sulfur dioxide requirements

§ 7651e - Allowances for States with emissions rates at or below 0.80 lbs/mmBtu

§ 7651f - Nitrogen oxides emission reduction program

§ 7651g - Permits and compliance plans

§ 7651h - Repowered sources

§ 7651i - Election for additional sources

§ 7651j - Excess emissions penalty

§ 7651k - Monitoring, reporting, and recordkeeping requirements

42 U.S. Code § -

§ 7651m - Enforcement

§ 7651n - Clean coal technology regulatory incentives

42 U.S. Code § -

§ 7661 - Definitions

§ 7661a - Permit programs

§ 7661b - Permit applications

§ 7661c - Permit requirements and conditions

§ 7661d - Notification to Administrator and contiguous States

§ 7661e - Other authorities

§ 7661f - Small business stationary source technical and environmental compliance assistance program

§ 7671 - Definitions

§ 7671a - Listing of class I and class II substances

§ 7671b - Monitoring and reporting requirements

§ 7671c - Phase-out of production and consumption of class I substances

§ 7671d - Phase-out of production and consumption of class II substances

§ 7671e - Accelerated schedule

§ 7671f - Exchange authority

§ 7671g - National recycling and emission reduction program

§ 7671h - Servicing of motor vehicle air conditioners

§ 7671i - Nonessential products containing chlorofluorocarbons

§ 7671j - Labeling

§ 7671k - Safe alternatives policy

42 U.S. Code § -

§ 7671m - Relationship to other laws

§ 7671n - Authority of Administrator

42 U.S. Code § -

§ 7671p - International cooperation

§ 7671q - Miscellaneous provisions

Title 40 published on 2013-07-01

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 40 CFR 86 after this date.

  • 2014-08-08; vol. 79 # 153 - Friday, August 8, 2014
    1. 79 FR 46356 - Emergency Vehicle Rule—SCR Maintenance and Regulatory Flexibility for Nonroad Equipment
      GPO FDSys XML | Text
      ENVIRONMENTAL PROTECTION AGENCY
      Final rule.
      This rule is effective on September 8, 2014.
      40 CFR Parts 86 and 1039