Code of Federal Regulations Title 40. Protection of Environment § 40.89.418 Raw emission sampling calculations

(1) For measurements using the mass flow method, see § 89.416(a).

(2) For measurements using the fuel consumption and exhaust gas concentrations method, use the following equations:

Where:

K = 3.5

(3) Humidity values may be calculated from either one of the following equations:

(1) For measurements using the mass flow method (see § 89.416(a)):

Where:

α = H/C mole ratio of the fuel.

(2) For measurements using the fuel consumption and exhaust gas concentrations method (see § 89.416(b)):

(1) For the calculation of u, v, and w for NO_X (as NO₂), CO, HC (in paragraph (e) of this section as CH_1.80), CO₂, and O2:

Where:

w = 4.4615.10⁻⁵ x M if conc. in ppm

w = 4.4615.10⁻¹ x M if conc. in percent

v = w

u = w/ρ_Air

M = Molecular weight

ρ_Air = Density of dry air at 273.15 °K (0 °C), 101.3 kPa = 1.293 kg/m³

(2) For real gases at 273.15 °K (0 °C) and 101.3 kPa:  For the calculation of u, v, and w

w= gas x 10^-6 if conc. in ppm

v=w

u = w/p_Air

p_Gas = Density of measured gas at 0 °C, 101.3 kPas in g/m³

(3) General formulas for the calculation of concentrations at temperature (designated as T) and pressure (designated as p):

—for ideal gases

—for real gases

with:

1% = 10⁴ ppm

M = Molecular weight in g/Mo1

M_v = Molecular Volume = 22.414 x 10³ m³/Mol for ideal gases

T = reference temperature 273.15 K

p = reference pressure 101.3 kPa

T = Temperature in °C

p = pressure in kPa

p_Gas = Density of the measured gas at 0 °C, 101.3 kPa

Conc. = Gas concentration

(g)(1) The emission shall be calculated for all individual components in the following way where power at idle is equal to zero:

(2) The weighting factors and the number of modes (n) used in the calculation in paragraph (g)(1) of this section are according to § 89.410.