Emission Factors

To determine an engine’s emissions, an owner/operator may use:

  1. Default SBCAPCD Diesel Engine Emission Factors – For use with older engines (see the first table presented below), or
  2. USEPA emission standards for Tier 1 – 4 engines (see the second table presented below)
Default SBCAPCD Diesel Engine Emission Factors
Pollutant Emission Factor Units Ref
PM 1.0 g/bhp-hr 1
NOx (as NO2) 14.1 g/bhp-hr 1
NMHC 1.12 g/bhp-hr 1
NMHC+NOx 15.22 g/bhp-hr 1
CO 3.0 g/bhp-hr 1
SOx (as SO2) 3.67 * wt %S g/bhp-hr 2

basis: (1) USEPA AP-42, Table 3.3-1, (2) USEPA AP-42, Table 3.3-2, where S = wt  % of sulfur (eg, for S = 0.05 wt %: SOx = (3.67)*(0.05) = 0.183 g/bhp-hr.  Assume NMHC = ROC

USEPA Emission Standards for Tier 1 – 4 engines
 Engine Power (hp) Model Years  Regulation  Emission Standards (g/hp-hr) Year the Std Takes Effect
 HC a, c VHC b  NOx a, c  NMHC+NOx a  CO a  PM a
 50 to <75  1998-2003  Tier 1 6.90 1998
 2004-2007  Tier 2 0.40 0.3996 5.20 5.60 3.70 0.30 2004
 2008-2012  Tier 3 0.20 0.1998 3.3 3.50 3.70 0.30 2008
 2013 +  Tier 4 0.20 0.1998 3.3 3.50 3.70 0.02 2013
>75 to <100  1998-2003  Tier 1 6.90 1997
 2004-2007  Tier 2 0.40 0.3996 5.20 5.60 3.70 0.30 2004
 2008-2011  Tier 3 0.20 0.1998 3.3 3.50 3.70 0.30 2008
 2012-2013  Tier 4 transitional 0.14 0.1399 0.30 3.70 0.01 2012
 2014 +  Tier 4 0.14 0.1399 0.30 3.70 0.01 2014
>100 to <175  1997-2002  Tier 1 6.90 1997
 2003-2006  Tier 2 0.40 0.3996 4.5 4.90 3.70 0.22 2003
 2007-2011  Tier 3 0.20 0.1998 2.8 3.00 3.70 0.22 2007
 2012-2013  Tier 4 transitional 0.14 0.1399 0.30 3.70 0.01 2012
 2014 +  Tier 4 0.14 0.1399 0.30 3.70 0.01 2014
>175 to <300  1996-2002  Tier 1 1.00 0.9990 6.90 8.50 0.40 1996
 2003-2005  Tier 2 0.40 0.3996 4.5 4.90 2.60 0.15 2003
 2006-2010  Tier 3 0.20 0.1998 2.8 3.00 2.60 0.15 2006
 2011-2013  Tier 4 transitional 0.14 0.1399 0.30 2.60 0.01 2011
 2014 +  Tier 4 0.14 0.1399 0.30 2.60 0.01 2014
>300 to <600  1996-2000  Tier 1 1.00 0.9990 6.90 8.50 0.40 1996
 2001-2005  Tier 2 0.30 0.2997 4.5 4.80 2.60 0.15 2001
 2006-2010  Tier 3 0.20 0.1998 2.8 3.00 2.60 0.15 2006
 2011-2013  Tier 4 transitional 0.14 0.1399 0.30 2.60 0.01 2011
 2014 +  Tier 4 0.14 0.1399 0.30 2.60 0.01 2014
>600 to <750  1996-2001  Tier 1 1.00 0.9990 6.90 8.50 0.40 1996
 2002-2005  Tier 2 0.30 0.2997 4.5 4.80 2.60 0.15 2002
 2006-2010  Tier 3 0.20 0.1998 2.8 3.00 2.60 0.15 2006
 2011-2013  Tier 4 transitional 0.14 0.1399 0.30 2.60 0.01 2011
 2014 +  Tier 4 0.14 0.1399 0.30 2.60 0.01 2014
 >750 except generator sets  2000-2005  Tier 1 1.00 0.9990 6.90 8.50 0.40 2000
 2006-2010  Tier 2 0.30 0.2997 4.5 4.80 2.60 0.15 2006
 2011-2014  Tier 4 transitional 0.30 0.2997 2.60 2.60 0.08 2011
 2015 +  Tier 4 0.14 0.1399 2.60 2.60 0.03 2015
 Generator sets >750 to <1200  2000-2005  Tier 1 1.00 0.9990 6.90 8.50 0.40 2000
 2006-2010  Tier 2 0.30 0.2997 4.5 4.80 2.60 0.15 2006
 2011-2014  Tier 4 transitional 0.30 0.2997 2.60 2.60 0.08 2011
 2015 +  Tier 4 0.14 0.1399 0.50 2.60 0.02 2015
 Generator sets >1200  2000-2005  Tier 1 1.00 0.9990 6.90 8.50 0.40 2000
 2006-2010  Tier 2 0.30 0.2997 4.5 4.80 2.60 0.15 2006
 2011-2014  Tier 4 transitional 0.30 0.2997 0.50 2.60 0.08 2011
 2015 +  Tier 4 0.14 0.1399 0.50 2.60 0.02 2015
Notes:

a Nonroad CI Engine Emission Standards from Title 13, California Code of Regulations, Section 2423 (ARB Executive Order “Std”).

b VHC = Total Hydrocarbons (THC) minus methane and ethane fractions.  Equivalent APCD standard. (Highlighted in Orange)  See Conversion Factors to Hydrocarbon Emission Components, Report No. NR-002a, US EPA, 5/2003.  {VHC = ROC}

c Tier 2 and Tier 3 HC and NOx equivalent standards used to determine the NMHC + NOx standard.  (Highlighted in blue)

For more information or assistance, call the APCD at (805) 961-8800 or e-mail us at [email protected].

Return to DICE ATCM

air pollution control district logo

New Phone Numbers
The District has new direct lines for all staff, as well as for all of our phone lines, including our main phone number and Complaints line. You can find our new phone numbers on this webpage.

Nuevos números de teléfono
El Distrito tiene nuevos números de teléfono para comunicarse con el personal directamente, así como también para todas nuestras líneas telefónicas, incluyendo nuestro número principal y el de las Quejas. Puede encontrar nuestros nuevos números de teléfono en esta página web.