The Non-Road Mobile Machinery (Emission of Gaseous and Particulate Pollutants) Regulations 1999

Calculation of emission mass flow rates

1.3.4.  The emission mass flow rates for each mode shall be calculated as follows:

(a) For the raw exhaust gas(1)

Gas_mass = u × conc × G_EXHW

or:

Gas_mass = v × conc × V_EXHD

or:

Gas_mass = w × conc × V_EXHD

(b) For the dilute exhaust gas(1)

Gas_mass = u × conc_c × G_TOTW

or:

Gas_mass = w × conc_c × V_TOTW

where:

con_c

=

is the background corrected concentration

conc_c

=

conc − conc_d × (1 − (1/DF))

or:

DF = 13.4 / concCO₂.

The coefficients u – wet, v – dry, w – wet shall be used according to the following table:

• Gas	u	v	w	conc
  NOX	0.001587	0.002053	0.002053	ppm
  CO	0.000966	0.00125	0.00125	ppm
  HC	0.000479	—	0.000619	ppm
  CO2	15.19	19.64	19.64	percent

• The density of HC is based upon an average carbon to hydrogen ratio of 1:1.85.

(1)

In the case of NO_X, the NO_X concentration (NO_Xconc or NO_Xconc_c) has to be multiplied by K_HNOX(humidity correction factor for NO_X quoted in the previous section 1.3.3) as follows:

K_HNOX× conc or K_HNOX× conc.