EPA-AA-TEB-80-19
NOx National Emission Inventory Estimates
              Mark Wolcott
              August 1980
       Test and Evaluation Branch
   Emission Control Technology Division
   Mobile Source Air Pollution Control
   Office of Air, Noise, and Radiation
     Environmental Protection Agency

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                                     -2-
                   NOx National Emission Inventory Estimates

This  report  presents  the current  and  projected estimates  of  the  national
emissions inventory for  oxides of nitrogen (NOx).  A description of the meth-
odology used to  calculate the inventory is also provided.   These inventories
were  used  in the acid rain  analysis performed  in support  of  the Draft Regu-
latory  Analysis, Environmental Impact  Statement and  NOx  Pollutant  Specific
Study for Proposed  Gaseous  Emission for 1985  and Later Model Year Light Duty
Trucks and  Heavy Duty Engines  (referred  to hereafter as  the  1985  NOx Regu-
latory  Analysis).   (Reference 1.)   The emphasis  of   this  report, is  on the
projected change in national NOx emissions from 1977  to 1999.   The impact of
the  proposed regulations  on  rain  acidity  is  assumed  to be proportional  to
total NOx  emissions.   While  the inventories  were  used to  support  the draft
regulatory analysis, they can also be used independently since an inventory is
presented for  the  currently  promulgated regulations as well as  for  the pro-
posed regulations.

Acid  rain  is a  term used  to describe precipitation that is  more acidic than
normal  precipitation.   Usually, the  acid  is  either  nitric or  sulfuric.   In
simplest terms,  the amount  of nitric  acid  in the air  is  assumed  to be pro-
portional to the  amount of  NOx emitted into the atmosphere.   Since trans-
portation sources  contribute  a  large  share of NOx to  the atmosphere, regu-r
lations that reduce NOx  are expected to decrease the nitric acid contribution
to acid rain.

Acid  rain has  been linked to declining fish populations in the Northeast.  In
the  Adirondack  Mountains, 45  percent  of the  lakes above 600 altitude meters
are  devoid of  fish.   Fifty years ago  fish  were absent from only 4 percent of
these same  lakes.   Foliage  can also be  affected.   Tissue  death,  loss of leaf
area  and  accelerated  loss of  nutrients occurs  in the  presence of  acid rain.
In  addition, damage  to  certain materials has been reported.   High acidity
seems to  promote corrosion  of steel  and  copper.  (References 2,  3, and 4.)
Clearly, the potential economic  cost  of acid rain induced  damage  is large.

Base Year Emission Inventory

No attempt is made in this paper to assess the  costs of acid rain.  Instead, a
national NOx inventory and,  therefore, the potential  degree  of rain acidity,
is developed from available data.

Total highway  mobile  source  emissions were calculated  for  each  of  the three
regions of the country (low altitude 49-state,  high altitude, and California).
Since the emission  factors  for the three regions are different, the number of
vehicle miles  traveled  (VMT)  by each  type  of  vehicle  must  be estimated for
each  of  the regions in  order to calculate a  total  emissions inventory.  The
procedure described in  Reference 5 was  used to distribute  FHwA estimated VMT
among  four   vehicle  classes:   light duty vehicles  (LDV),  light  duty trucks
(LOT),  heavy duty  gasoline  trucks  (HDG) and  heavy duty diesel trucks  (HDD).
The  national VMT distibution by vehicle class  was assumed to apply in each of
the  three  regions.   However,  no adjustment  was made  to account  for  the fact
that  total VMT  is  accumulated under both urban and rural driving conditions.
Since the  emission factors  used to estimate   future  inventories  assume that

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                                      -3-
mileage is accumulated under only urban driving conditions, all VMT in each of
the three regions  was also assumed to be  accumulated under those conditions.
Further,  since  individual  county  VMT  is  not  readily  available  for  high
altitude  counties,  total Colorado  VMT  was  used  as a  surrogate for  high
altitude VMT.  Low altitude 49-state VMT was assumed to equal total nationwide
VMT minus high altitude and California VMT.

Table  1  presents  the highway mobile  source NOx  inventory  for calendar year
1977.   The  emission  factors  came  from  a  modified  version  of  MOBILE1.
(Reference  6.)   The  modified emission  estimates correspond to  the emission
factors  used in the  regulatory analysis for 1985 and later LDT  and HDV NOx.
VMT was derived from  FHwA figures.

As  Table  1   shows,  light duty  vehicles  accounted for 55  percent of national
1977 highway mobile  source NOx emissions.  Light duty trucks accounted for 13
percent.   Heavy  duty gasoline  and  diesel  trucks  accounted   for  11  and  21
percent, respectively, of total highway mobile source  emissions.

Off-highway mobile sources, which are not listed  in Table  1, include aircraft,
vessels  and locomotives.   The  1977  levels  were estimated according  to the
standard  National   Emissions  Data  System   (NEDS)   procedures  and  totaled
2,160,000 tons.

Table  2  presents  the   1977  NEDS  stationary   area  source   NOx  inventory.
(Reference  7.)  These six categories also correspond to those used in the 1985
NOx  Regulatory Analysis.   During  1977, residential  oil   and  gas combustion
accounted  for  30  percent  of  total  stationary  area source  NOx  emissions.
Commercial  oil  and gas accounted for 24 percent  of emissions.  The industrial
coal and  industrial  oil  and  gas  sources accounted for 7  and 20 percent, res-
pectively,  of  stationary area source NOx.   All  other stationary  area sources
accounted for 18 percent.

All  stationary  area  sources  contributed   1,263,700  tons  of  NOx in   1977.
Stationary  point  sources, such as power plants,  contributed 11,057,100  tons.
Finally,  total mobile  sources  contributed  9,453,600 tons of NOx  in  1977.
According to the  estimation procedures  described, a grand total of 21,774,400
tons of NOx were emitted  into the atmosphere in 1977.  See Table 3.

Future Year Inventory

To  ascertain the  likely effect  of  the proposed  1985 LDT and HDV NOx  regu-
lations on  rain acidity,  it  is necessary to  project the national NOx inventory
for  the years  when the  regulation  would be  in  effect.   The  modified linear
rollback  model  (ROLLBACK) was  used to  project NOx  emission  inventories for
1985,  1990,  1995 and  1999.   (Reference 8.)   These are  also the  same projection
years  used  in the  air quality analysis performed  in support of  the forthcoming
1985  NOx Regulatory  Analysis.   To project base year  inventories  into the
future,  both growth and  future control  rate assumptions must be made.  Growth
refers  to  the  increase  in activity level of  each pollution source.  The two
levels  of  growth  considered in  this  paper  are  listed  in Table  4.  It  seems
likely that the actual growth rates will fall  within  the growth ranges  listed.
The growth  rates that are assumed for each emissions category are presented in

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                                     -4-
that table.   (Reference  9.)   For highway mobile sources the activity level is
measured  as  vehicle  miles traveled.   Other  measurement  units  for activity
levels are used for stationary sources.

Future  control  refers to  the degree  to which  emissions  are expected  to be
reduced given a  constant activity level.  Emissions are measured in units of
grams  per mile traveled  for  highway  mobile  sources.   Mobile  source  control
measures are implicit in the emission factors produced by the computer program
MOBILEl.   (Reference 6.)   To project the  effect of  highway mobile  source
controls,  the  ratios of  future  to base year emission  factors  are applied to
the base year inventory.   Table 5 lists the NOx highway mobile source emission
factor  ratios  used to estimate  future  emissions.   The MQBILE1  results from
which these ratios were calculated are presented in Appendix A.  In 1980 light
duty vehicles are  expected to emit 2.66 grams of NOx per mile traveled.  This
rate is 82 percent of the corresponding 1977 level.

The  ratios presented in Table 5  are not identical to  those  presented  in the
regulatory analysis.   Since  the  1977 individual AQCR  emissions inventories
have not  yet  been published,  1976 NEDS  inventories  were used in the 1985 NOx
Regulatory Analysis.   For  that  analysis,  emission factor  ratios  were also
calculated from  the  1976 base year.  However, the national NOx inventory work
was  based on  calendar  year  1977.   Hence,  the  ratios  presented in Table  5
reflect a  1977 base year rather than the 1976 base year used in the regulatory
analysis.

In the  case  of  stationary sources, the  control  rates  are applied to the base
inventory  directly.   New source  performance standards  (NSPS)  were assumed to
apply  to  newly constructed stationary area  sources  beginning in  1983.  The
NSPS control  efficiencies are also listed in Table 4.   Reasonable available
control technology (RACT) was not assumed for existing stationary area sources
since in  1977  only a few areas violated the present 100 ug/m  annual average
N02 National Ambient Air Quality Standard (NAAQS).  Finally, a zero retirement
rate was  assumed  for all stationary sources.  This is a worst case assumption
in the  sense  that emission projections would be lower with a positive retire-
ment rate.

Figures 1  and  2  present  the results of the inventory projections and show how
the  relative contributions  of the various emission  sources  change over time.
These  figures assume  no  further  control  other  than  what has  already been
mandated.   Figure 1  shows the  contribution  of mobile, stationary area and
stationary  point  sources  for the 1977  base year  and each  projection year
thereafter, assuming that low growth rates prevail during this time.  Figure 2
shows the  relative contribution of each mobile source to total mobile emissions
for each evaluation year.

As  indicated in  Figure  1, total  NOx emissions  are expected  to increase in
every  projection  year  from  1977  through  1999.  Growth in  stationary point
source  emissions  overshadows  the reduction in mobile source emissions through
1985.  Thereafter, both mobile and stationary source emissions are expected to
increase.  By  1999,  mobile source emissions are  expected  to be  greater  than
they were in  1977.  This increase in mobile source emissions can be traced to
growth  in both  heavy duty diesel and off-highway mobile sources.  As Figure 2
shows,  over  that  two decade period the  proportion of  mobile source emissions

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                                     -5-
accounted for by  light  duty vehicles declines from 42  to 25 percent.  On the
other hand,  the proportion  of  emissions accounted for by heavy  duty diesels
more  than  doubles,  from  16 to 37  percent.   The proportion  of mobile source
emissions accounted for by  off-highway vehicles also  increases,  from 23 to 27
percent.

Figures 3 and 4 present the inventory results assuming that high  growth rates
prevail.  The pattern shown in Figure 1 is accentuated in Figure  3.   With high
growth,  total   1999  NOx  emissions  are  expected  to  increase an  additional
3,352,600 tons  from the 1999 low growth  projection.  The 1999 NOx level rep-
resents  a  44 percent  increase from  the 1977 level.   Further,  the  share of
total 1999 emissions accounted  for by mobile sources increases from 35 to 42
percent.  The  decrease in  the  relative  contributions  of HDD and  HDG trucks
shown in Figure 4, as  compared to Figure 2,  reflects  the fact that the growth
rates associated with these two vehicle classes were held constant between the
high  and  low growth scenarios.   The  growth  rates associated with the other
three vehicle classes were increased by one percentage point each  from the low
to high growth scenarios.

1985 NOx Regulatory Analysis

The  projections presented  in Figures  1  and 2 assume  the degree  of mobile
source  control  mandated by present regulations.  More  stringent  NOx controls
on  light  duty  trucks and heavy duty  engines are being proposed  for 1985 and
later model  year  vehicles.   Currently, the proposed regulations  are 0.9 gram
per mile for LDT and 1.7 grams per brake horsepower hour for HDV  and represent
a 75 percent reduction from 1972-1973 baseline NOx emissions.

The  emission factor  ratios  that were used to adjust  the inventory to reflect
these additional controls  are presented in Table 6.  (Reference  10.)  For the
reasons previously stated, these ratios are not identical to those used in the
regulatory analysis.  Rather,  they are the ratios of  the future  year emission
factors divided by the 1977 base year emission factors.

The  effect of  imposing  the more stringent controls is  presented  in Figures 5
through 8.   With  the  currently promulgated mobile source controls on NOx, the
total NOx  emissions  in 1999 are  expected to be 29 percent  greater than the
1977 levels.  Total NOx emissions are projected to increase by only 13 percent
over the same time frame,  if the more stringent controls proposed for 1985 and
later model  year  light duty trucks and heavy duty engines are implemented.  A
further comparision of Figures 1 and 5 shows that if low growth rates prevail,
there would  be a 35 percent reduction from the base case in 1999  NOx emissions
from  mobile  sources  due  to the  proposed 1985 and  later  NOx regulations.  If
high  growth  rates prevail,  there would  be  a 28  percent reduction in mobile
source  NOx.  Similarly, if low growth rates prevail,  the total 1999 NOx emis-
sions  for  all  sources would be reduced  13 percent from  the  base case due to
the  regulations.  If high rates prevail, the reduction due to the regulations
would be 12  percent for all sources.

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                                     -6-
Summary

Estimates of the national NOx emission inventory constructed for this analysis
indicate that  total NOx  emissions  will increase in  every  calendar  year from
1977 through 1999.   Without  further regulatory action, total NOx emissions in
1999 are projected  to  be 29 percent greater  than 1977 levels.  With the more
stringent controls  proposed for  1985  and later model year light  duty trucks
and heavy duty  engines,  total  NOx emissions are projected to increase by only
13 percent.   If one assumes a proportional relationship between the acidity of
rain and  total NOx  emissions,  then the  expected increases  in NOx  emissions
will have  a  detrimental effect  on the  nation's  buildings and  lakes.   The
proposed regulations would  limit  the damage by reducing potential nitric acid
content of acid rain.

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                                                                        Table 1
                                                  1977 Highway Mobile Sources NOx Emissions Inventory
Low-Altitude 49-State

LDV
LDT
HDG
HDD
Total
VMT
(x!0b miles)
1,010,713
175,074
66,669
55,260
1,307,716
EF
(g/m)
3.24
4.37
10.03
22.10

California
Emissions VMT
(tons) (x!0b miles)
3,609,750
843,349
737,105
1,346,193
6,536,397
116,164
20.122
7,662
6,352
150,300
EF
(g/m)
2.89
4.205
9.95
21.41

High Altitude
Emissions VMT EF
(tons) (xlO miles) (g/m)
370,061
93,270
84,037
149,910
697,278
14,338
2.483
946
784
18,551
2.22
2.82
6.40
12.10

Emissions
(tons)
35,087
7,718
6.674
10,457
59,936
National Total
VMT
(x!0b miles)
1,141,215
197,679
75,277
62,396
1,476,567
Emissions
(tons)
4,014,898
944,337
827,816
1,506,560
7,293,611
Percent
55.0
12.9
I
11.4 7
20.7
100.0
* Modified MOBILE1 emission factors and FHwA VMT were used to develop the inventory.
The MOBILE1 modifications are described in Reference 6.

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                                      -8-
                                    Table 2

              NEDS 1977 Stationary Source NOx Emissions Inventory
Residential Oil and Gas
     Anthracite Coal
     Bituminous Coal
     Distillate Oil
     Residual Oil
     Natural Gas

Commercial Coal - Area
     Anthracite
     Bituminous

Commercial Oil and Gas - Area
     Residual Oil
     Distillate Oil
     Natural Gas

Industrial Coal
     Anthracite
     Bituminous
     Coke

Industrial Oil and Gas - Area
     Residual Oil
     Distillate Oil
     Natural Gas
     Process Gas

Other - Area

Total
                                           Sub-Total
                                            (tons)
  1,494
    922
166,358
      0
214,674
  7,378
  1,358
128,813
 45,570
130,258
     58
 84,275
     49
 80,316
 46,796
122,117
     86
                    Totals
                    (tons)

                    383,448
                      8,736
                    304,641
                     84,382
                    249,315
                     233,189

                    ,263,711

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                            -9-
                         Table 3

          1977 National NOx Emissions Inventory

                                         Total NOx Emissions
Source                                       (1000 Tons)

Stationary Area                               1,263.7
Stationary Point                             11,057.1
Mobile                                        9,453.6

Total                                        21,774.4

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                                      -10-
                                    Table 4

    Mobile and Stationary Source Growth Rates and NSPS Control Efficiencies
                                                                   NSPS @
                                                                  Control
                                                                 Efficiency
                                                                 (percent)
Mobile Sources
     Light Duty Vehicles
     Light Duty Trucks
     Heavy Duty Gasoline Trucks
     Heavy Duty Diesel Trucks
     Off-Highway Vehicles

Stationary Area Sources
     Residential Oil and Gas
     Commercial Coal
     Commercial Oil and Gas
     Industrial Coal
     Industrial Oil and Gas
     All Other

Stationary Point Sources
  Low
 Growth
(percent)

  +1.0
  +1.0
  -2.0
  +5.0
  +1.0
  +1.0
  +1.0
  +1.0
  +1.0
  +1.0
  +1.0

  +2.5
  High
 Growth
(percent)

   +3.0
   +3.0
   -2.0
   +5.0
   +3.0
   +2.0
   +2.0
   +2.0
   +2.0
   +2.0
   +2.0

   +2.5
50
24
50
24
50
 0
@ Assumed to apply in 1983 and later calendar years.
* Mobile  source  control  efficiencies are incorporated in the emission factors
predicted by MOBILE1 and are therefore not estimated separately.

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                                         -11-
                                    Table 5
                                                                 2
            Mobile Source Emission Factor Ratios - Base Case (xlO )


                               Projection
Region                            Year*           LDV       LDT       HDG       HDD

Low Altitude                       80
Non-California                     85
                                   90
                                   95
                                   99

California                         80
                                   85
                                   90
                                   95
                                   99

High Altitude                      80
                                   85
                                   90
                                   95
                                   99

* 1977 Base Year
82
56
49
48
48
78
56
52
52
52
94
73
70
71
71
85
65
59
57
57
81
55
45
43
43
87
69
65
64
64
97
96
96
95
95
94
85
78
75
74
98
97
95
93
93
96
88
86
86
86
84
69
62
61
61
100
101
102
102
102

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                                         -12-
                                    Table 6
                                                                  2
          Mobile Source Emission Factor Ratios - Control Case (xlO )

                          Projection
Region                       Year*           LDV       LDT       HDG       HDD

Low Altitide                  80
Non-California                85
                              90
                              95
                              99

California                    80
                              85
                              90
                              95
                              99

High Altitude                 80
                              85
                              90
                              95
                              99
* 1977 Base Year
82
56
49
48
48
78
56
52
52
52
94
73
70
71
71
85
63
40
29
26
81
55
45
' 43
43
87
68
50
41
39
97
91
50
32
27
94
82
46
30
26
98
93
58
43
39
96
81
33
21
19
84
65
30
20
19
100
93
39
25
22

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                                    -13-
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                                                         CATEGORY
                                                          STATIONARY AREA
                                                          STATIONARY  POINT
                                                          MOBILE TOTAL
      1977     1980     198S     1990
                       PROJECTION TEBR
1995
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                                    -14-
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                                  -15-
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                                         -16-
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                                       -17-
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                                                         CRTECORT
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                                    -18-
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-------
                                  -19-
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                                    -20-
FIGUflE 8                   NOX NfUlONflL INVENTORY PROJECTION
198S LOT. MOV REGULflTORY fiNflLYSJSi CONTHOLCflSE - MICH GHOHTH
                                                         CflTEGORY
PERCENT Of MOBILE NOX EMISSIONS
•-> ro o> ff tn at -j CD 
-------
                                      -21-
References

1.   Draft Regulatory Analysis, Environmental Impact Statement and NOx Pollutant
     Specfic Study for Proposed Gaseous Emissions or 1985 and Later Model Year
     Light Duty Trucks and Heavy Duty Engines,  U.S.  Environmental  Protection
     Agency, Ann Arbor, Michigan, 1980.

2.   Likens,  G.E.,  "Acid  Precipitation",  Chemical Engineering News  54  (48),
     pages 29-44, 1976.

3.   Tamm, C.O.  and E.B.  Cowling, "Acid Precipitation and Forest Vegitation",
     Proceedings of the First International Symposium on Acid Precipitation
     and the Forest Ecosystem,  May  12-15,  1975,  Columbus,  Ohio,  U.S.  Forest
     Service  General  Technical  Report  NE-23, Northeastern  Forest Experiment
     Station, Upper Darby, Pennsylvania, pages 845-856, 1976.

4.   Nriagn,  J., "Deteriorative  Effects  of  Sulfer Pollution on Materials",
     Sulfer in the Environment Part II; Ecological Impacts,   John   Wiley  and
     Sons, New York, 1978.

5.   NADB Internal Operations Manual,  U.S.  Environmental Protection Agency,
     Research Triangle Park,  North  Carolina,  Section 2, Chapter 8, Subject 4,
     pages 11-12.

6.   Mobile Source Emission Factors:  Final Document,  EPA 400/9-78-006,  U.S.
     Environmental Protection Agency, Washington, District of Columbia, March, 1978.

7.   AEROS Volume II, EPA  450/2-76-029,  U.S.  Environmental  Protection Agency,
     Research Triangle Park, North Carolina,  1976.

8.   N.  deNevers and  J.R. Morris,   "Rollback Modeling;  Basic and Modified",
     Journal of the Air Pollution Control Association,   25,   943,  September,
     1975.

9.   Freas,  W.P.,  "Data Base  for Air  Quality  Impact  Assessment  of  Proposed
     Heavy-Duty  Vehicle  Emission Standards",  Memorandum to M.  Wolcott, U.S.
     Environmental  Protection  Agency,  Ann  Arbor,  Michigan,  March,  1980.

10.  Wallace, J., "MOBILE1 Modifications and  Emission Rate Assumptions for the
     LOT  and HDV NOx  Regulatory Analysis",  Memorandum to  J. Anderson, U.S.
     Environmental Protection Agency, Ann Arbor, Michigan, June,  1980.

-------
                -22-
            Appendix A






Mobile Source Emission Factor Estimates

-------
                                    -23-
BASE CASE FOR THE NOX REG PACKAGE 5/02/80
   EMISSION FACTOR MODIFICATION PROFILE:
REGION
  1
  1
  1
  1
  1
  1
  1
  1
  2
  2
  3
  3
  3
  3
MODE
2
2
3
3
2
3
4
5
4
5
2
3
4
5
POLLUTANT
1
2
1
2
3
3
3
3
3
3
3
3
3
3
  FIRST MY  LAST MY
    1983
    1983
    1983
    1983
    1985
    1985*
    1985
    1985
    1985
    1985
    1985
    1985
    1985
    1985
    1999
    1999
    1999
    1999
    1999
    1999
    1999
    1999
    1999
    1999
    1999
    1999
    1999
    1999
DEL
0.35
4.31
0.35
4.31
0.11
0.11
0.0
0.0
0.0
0.0
0.11
0.11
0.0
0.0
ALTERED
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
  *NON-METH HC EMISSION FACTORS INCLUDE EVAP. HC EMISSION FACTORS

                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1977     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: 49-STATE    26.0/16.0/26.0 MPU (20.0)         20.&/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
6.68
59.18
3.24
LDT1
7.47
63.51
3.29
LDT2
10.27
78.24
5.45
HDG
20.40
253.67
10.03
(GM/MILE)
HDD
4.10
11.28
22.10
MC
10.72
35.23
0.14
ALL MODES
7.49
67.68
4.25
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1980     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: 49-STATE    26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
4.77
47.07
2.66
LDT1
5.89
57.14
2.73
LDT2
8.75
73.17
4.71
HDG
18.22
256.29
9.76
(GM/MILE)
HDD
4.10
11.28
21.20
MC
7.17
26.44
0.26
ALL MODES
5.66
57.37
3.67
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1985     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: 49-STATE    26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
                      COMPOSITE EMISSION FACTORS (GM/MILE)
               LDV
NON-METH HC:   1.88
EXHAUST  CO:  17.17
EXHAUST NOx:   1.81
 LDT1
 3.44
37.69
 2.42
 LDT2
 4.91
46.48
 3.28
  HDG
 12.43
221.91
  9.62
 HDD
 3.69
11.28
19.39
 MC
1.97
7.91
0.47
ALL MODES
   2.67
  29.05
   2.82

-------
                                    -24-
                               VEH.  TYPE:  LDV   LDT1  LDT2  HDG    HDD   MC
 CAL.  YEAR:  1990     TEMP:  75.0(F) .        0.803/0.058/0.058/0.045/0.031/0.005
 REGION:  49-STATE    26.0/16.0/28.0  MPH (20.0)         20.6/ 27.3/  20.6
  LDV  I/M PROGRAM STARTING  IN 1982,  STRINGENCY LEVEL 30%, MECH. TRAINING:  NO
  I/M  PROG.  BENEFITS APPLY  ONLY TO MODEL YEARS 1951 THROUGH  1999

                      COMPOSITE EMISSION FACTORS  (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
1.00
9.39
1.59
LDT1
2.46
29.28
2.39
LDT2
3.10
34.03
2.75
HDG
6.07
105.62
9.59
HDD
2.86
11.28
19.00
MC
0.46
3.36
0.18
ALL. MODES
1.49
16.33
2.60
                               VEH.  TYPE:   LDV   LDT1  LDT2  HDG    HDD   MC
 CAL.  YEAR:  1995     TEMP:  75.0(F)         0.803/0.058/0.058/0.045/0.031/0.005
 REGION:  49-STATE    26.0/16.0/26.0  MPH (20.0)         20.6/ 27.3/  20.6
  LDV  I/M PROGRAM STARTING  IN 1982,  STRINGENCY  LEVEL 30%, MECH. TRAINING: NO
  I/M  PROG.  BENEFITS APPLY  ONLY TO MODEL YEARS  1951 THROUGH  1999

                      COMPOSITE EMISSION FACTORS  (GM/MILE)

NON-METH HC:
EXHAUST CO :
EXHAUST NOx:
LDV
0.85
7.83
1.57
LDT1
2.12
26.83
2.41
LDT2
2.47
30.16
2.57
HDG
3.27
56.72
9.53
HDD
2.68
11.28
18.92
MC
0.31
2.87
0.16
ALL MODES
1.18
12.51
2.57
                               VEH. TYPE:   LDV   LDT1   LDT2   HDG   HDD   MC
 CAL. YEAR:  1999     TEMP:  75.0(F)         0.803/0.058/0.058/0.045/0.031/0.005
 REGION:  49-STATE    26.0/16.0/26.0 MPH (20.0)         20.6/  27.3/  20.6
  LDV I/M PROGRAM STARTING  IN 1982, STRINGENCY LEVEL 30%, MECH.  TRAINING: NO
  I/M PROG.  BENEFITS APPLY  ONLY TO  MODEL YEARS 1951  THROUGH  1999

                      COMPOSITE EMISSION FACTORS  (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
0.82
7.58
1.57
LDT1
2.03
26.03
2.43
LDT2
2.21
28.40
2.51
HDG
2.21
40.13
9.54
HDD
2.64
11.28
18.90
MC
0.31
2.87
0.16
ALL MODES
1.09
11.41
2.56
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   hC
 CAL. YEAR: 1977     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: CALIF.      26.0/16.0/26.0 MPH (20.0)         20. 6/ 27. 3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%,  11ECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
                      COMPOSITE EMISSION FACTORS (GM/MILE)
               LDV
NON-METH HC:   6.73
EXHAUST  CO:  53.91
EXHAUST NOx:   2.89
LDT1
7.34
63.52
3.03
LDT2
10.71
77.47
5.38
HDG
25.41
264.26
9.95
HDD
4.35
29.45
21.41
MC
10.42
36.05
0.14
ALL MODES
7.78
64.45
3.92

-------
                                   -25-
                               VEH.  TYPE:   LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR:  1980     TEMP: 75.0(F).        0.803/0.058/0.058/0.045/0.031/0.005
 REGION:  CALIF.      26.0/16.0/26.0  MPH (20.0)         20.6/  27.37 20.6
  LDV I/M PROGRAM STARTING IN 1982,  STRINGENCY LEVEL 30%,  MECH. TRAINING: NO
  I/M PROG.  BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999

                      COMPOSITE EMISSION FACTORS (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
4.60
37.67
2.26
LDT1
5.45
53.43
2.50
LDT2
8.42
70.34
4.34
HDG
19.17
254.91
9.33
HDD
4.39
27.88
18.04
MC ALL MODES
6.88
27.36
0.26 .
5.53
49.90
3.19
                               VEH. TYPE:   LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR:  1985     TEMP: 75.0(F)         0.803/0.058/0.058/0.045/0.031/0.005
 REGION:  CALIF.       26.0/16.0/26.0 MPH (20.0)         20.6/  27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%,  MECH. TRAINING: NO
  I/M PROG.  BENEFITS APPLY ONLY TO  MODEL YEARS 1951 THROUGH 1999
                      COMPOSITE EMISSION FACTORS (GM/MILE)

NON-METH HC:
EXHAUST CO :
EXHAUST NOx:
LDV
1.79
15.14
1.61
LDT1
2.63
26.40
1.93
LDT2
4.09
39.07
2.67
HDG
11.11
193.16
8.49
HDD
3.68
27.20
14.80
                                                             MC
                                                            1.48
                                                            8.46
                                                            0.47
        ALL MODES
           2.45
          25.53
           2.40
                               VEH. TYPE:   LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1990     TEMP: 75.0(F)         0.803/0.058/0.058/0.045/0.031/0.005
 REGION: CALIF.      26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%,  MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO  MODEL YEARS 1951 THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
1.00
10.05
1.50
LDT1
1.63
15.91
1.66
LDT2
2.24
21.70
2.15
EDG
5.91
93.40
7.74
(GM/MILE)
HDD
2.97
27.02
13.37
MC
0.40
3.46
0.18
ALL MODES
1.39
15.31
2.19
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1995     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: CALIF.      26.0/16.0/26.0 MPH (20.0)         20. 6/ 27. 3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
                      COMPOSITE EMISSION FACTORS (GM/MILE)
NON-METH HC:
EXHAUST  CO:
EXHAUST NOx:
LDV
0.86
8.79
1.49
LDT1
1.25
12.28
1.63
LDT2
1.51
15.53
2.01
HDG
3.13
52.57
7.45
HDD
2.83
27.00
13.06
 MC
0.31
2.87
0.16
ALL MODES
   1.08
  11.88
   2.15

-------
                                   -26-
                              VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
CAL. YEAR: 1999    'TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
REGION: CALIF.      26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
 LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECH. TRAINING: NO
 I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999

                     COMPOSITE EMISSION FACTORS (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
0.83
8.60
1.49
LDT1
1.17
11.12
1.62
LDT2
1.29
12.60
2.00
HDG
2.27
38.16
7.37
HDD
2.80
27.00
13.01
MC
0.31
2.87
0.16
ALL MODES
•1.00
10.85
2.14
                              VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
CAL. YEAR: 1977     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
REGION: HI-ALT.     26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
 LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECti. TRAINING: NO
 I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
8.47
83.67
2.22
LDT1
9.37
89.22
2.19
LDT2
13-39
118.42
3.45
HDG
40.33
401.39
6.40
(GM/MILE)
HDD
5.86
48.98
12.10
MC
13.96
48.62
0.08
ALL MODES
10.19
99.06
2.77
                              VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
CAL. YEAR: 1980     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
REGION: HI-ALT.     26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
 LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECH. TRAINING: NO
 I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999

                     COMPOSITE EMISSION FACTORS (GI-1/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
5.93
63.85
2.09
LDT1
7.18
75.59
1.85
LDT2
11.33
105.81
3.05
HDG
36.35
386.96
6.28
HDD
5.93
45.73
12.16
MC
10.08
36.30
0.16
ALL MODES
7.70
80.80
2.62
                              VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
CAL. YEAR:  1985     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
REGION: HI-ALT.     26.0/16.0/26.0 MPH  (20.0)         20.6/ 27.3/ 20.6
 LDV I/M PROGRAM STARTING IN  1982, STRINGENCY LEVEL 30%, MECH. TRAINING: NO
 I/M PROG.  BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
2.17
20.87
1.62
LDT1
3.87
43.78
1.69
LDT2
5.94
57.33
2.21
HDG
20.78
275.33
6.19
(GM/MILE)
HDD
4.71
39.44
12.27
MC
2.70
10.49
0.17
ALL MODES
3.40
36.29
2.19

-------
                                    -27-
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1990     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: HI-ALT.     26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%,  MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999

                      COMPOSITE EMISSION FACTORS (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
1.05
9.90
1.55
LDT1
2.12
21.89
1.71
LDT2
3.04
28.82
1.96
HDG
9.50
119.80
6.05
HDD
3.18
29.65
12.29
MC
0.51
3.58
0.15
ALL MODES
1.67
17.22
2.11
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1995     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: HI-ALT.     26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
0.86
7.89
1.57
LDT1
1.52
15.16
1.75
LDT2
1.95
18.91
1.87
HDG
4.49
61.74
5.94
(GM/MILE)
HDD
2.88
27.54
12.30
MC
0.31
2.88
0.16
ALL MODES
1.18
11.96
2.12
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1999     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: HI-ALT.     26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%,  MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 19D9
NON-METH HC:
EXHAUST  CO:
EXHAUST NOx:
       COMPOSITE EMISSION FACTORS (GM/MILE)
LDV      LDT1     LDT2     HDG      HDD       MC     ALL MODES
0.82     1.33     1.48     2.55     2.81     0.31       1.03
7.58    12.49    14.29    40.86    27.14     2.87      10.34
1.57     1.77     1.85     5.93    12.30     0.16       2.12

-------
                                    -28-
CONTROL CASE FOR THE NOX REG PACKAGE 5/02/80

  *NON-METH HC EMISSION FACTORS INCLUDE EVAP. HC EMISSION FACTORS

                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC.
 CAL. YEAR: 1977     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: 49-STATE    26.0/16.0/26.0 MPH (20.0)         20.6/  27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 302, MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999

                      COMPOSITE EMISSION FACTORS (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
6.68
59.18
3.24
LDT1
7.47
63.51
3.29
LDT2
10.27
78.24
5.45
HDG
20.40
253.67
10.03
HDD
4.10
11.28
22.10
MC
10.72
35.23
0.14
ALL' MODES
7.49
67.68
4.25
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1980     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: 49-STATE    26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
4.77
47.07
2.66
LDT1
5.89
57.14
2.73
LDT2
8.75
73.17
4.71
HDG
18.22
256.29
9.76
(GM/MILE)
HDD
4.10
11.28
21.20
MC
7.17
26.44
0.26
ALL MODES
5.66
57.37
3.67
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1985     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: 49-STATE    26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 302, MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999  '
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
1.88
17.17
1.81
LDT1
3.21
34.18
2.31
LDT2
4.72
43.45
3.21
HDG
12.43
221.91
9.15
(GM/MILE)
HDD
3.69
11.28
17.87
MC
1.97
7.91
0.47
ALL MODES
2.65
28.67
2.74
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1990     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: 49-STATE    26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 302, MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
1.00
9.39
1.59
LDT1
1.57
16.20
1.50
LDT2
2.26
21.74
1.97
HDG
6.07
105.62
5.05
(GM/MILE)
HDD
2.86
11.28
7.37
MC
0.46
3.36
0.18
ALL MODES
1.39
14.86
1.94

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                                   -29-
              -                 VEH. TYPE:   LDV   LDT1  LDT2  HDG -  HDD   MC
 CAL. YEAR:  1995    'TEMP:  75.0(F)         0.803/0.058/0.058/0.045/0.031/0.005
 REGION:  49-STATE    26.0/16.0/26.0 MPH (20.0)         20.6/  27.3/  20.6
  LDV I/M PROGRAM STARTING  IN 1982, STRINGENCY LEVEL 30%,  MECH.  TRAINING: NO
  I/M PROG.  BENEFITS APPLY  ONLY TO  MODEL YEARS 1951  THROUGH 1999

                      COMPOSITE EMISSION FACTORS (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
0.85
7.83
1.57
LDT1
0.98
10.13
1.16
LDT2
1.28
12.91
1.38
HDG
3.27
56.72
3.18
HDD
2.68
11.28
4.58
MC
0.31
2.87
0.16
ALL MODES
•1.05
10.54
1.70
                               VEH.  TYPE:   LDV   LDT1   LDT2  HDG   HDD   MC
 CAL. YEAR:  1999     TEMP:  75.0(F)         0.803/0.058/0.058/0.045/0.031/0.005
 REGION:  49-STATE    26.0/16.0/26.0  MPH (20.0)         20.6/  27.3/  20.6
  LDV I/M PROGRAM STARTING  IN 1982,  STRINGENCY LEVEL 30%,  MECH.  TRAINING: NO
  I/M PROG.  BENEFITS APPLY  ONLY TO MODEL YEARS 1951  THROUGH 1999

                      COMPOSITE EMISSION FACTORS (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
0.82
7.58
1.57
LDT1
0.76
7.56
1.08
LDT2
0.83
8.50
1.17
HDG
2.21
40.13
2.69
HDD
2.64
11.28
4.14
MC
0.31
2.87
0.16
ALL MODES
0.94
9.18
1.64
                               VEH. TYPE:   LDV   LDT1  LOT2  HDG   HDD   MC
 CAL. YEAR:  1977     TEMP:  75.0(F)         0.803/0.058/0.058/0.045/0.031/0.005
 REGION:  CALIF.       26.0/16.0/26.0 MPH (20.0)         20.6/  27.3/  20.6
  LDV I/M PROGRAM STARTING  IN 1982, STRINGENCY LEVEL 30%,  MECH.  TRAINING: NO
  I/M PROG.  BENEFITS APPLY  ONLY TO  MODEL YEARS 1951  THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
6.73
53.91
2.89
LDT1
7.34
63.52
3.03
LDT2
10.71
77.47
5.38
HDG
25.41
264.26
9.95
(GM/MILE)
HDD
4.35
29.45
21.41
MC
10.42
36.05
0.14
ALL MODES
7.78
64.45
3.92
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1980     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: CALIF.      26.0/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%,  MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
                      COMPOSITE EMISSION FACTORS (GM/MILE)
NON-METH HC:
EXHAUST  CO:
EXHAUST NOx:
LDV
4.60
37.67
2.26
LDT1
5.45
53.43
2.50
LDT2
8.42
70.34
4.34
HDG
19.17
254.91
9.33
HDD
4.39
27.88
18.04
MC
6.88
27.36
0.26
ALL MODES
5.53
49.90
3.19

-------
                                   -30-
                               VEH.  TYPE:   LDV  LDT1   LDT2  HDG   HDD   MC
 CAL. YEAR:  1985     TEMP:  75.0(F).        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: CALIF.      26.0/16.0/26.0  MPH (20.0)          20.6/  27.V  20.6
  LDV I/M PROGRAM STARTING  IN 1982,  STRINGENCY LEVEL 30%, MECE.  TRAINING: NO
  I/M PROG.  BENEFITS APPLY  ONLY TO MODEL YEARS 1951  THROUGH 1999

                      COMPOSITE EMISSION FACTORS  (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
1.79
15.14
1.61
LDT1
2.63
26.21
1.93
LDT2
4.08
38.85
2.67
HDG
11.11
193.16
8.15
HDD
3.68
27.20
13.88
MC
1.48
8.46
0.47
ALL MODES
'2.45 -
25.51
2.36
                               VEH. TYPE:   LDV   LDT1  ' LDT2  HDG   HDD   MC
 CAL. YEAR: 1990     TEMP:  75.0(F)         0.803/0.058/0.058/0.045/0.031/0.005
 REGION: CALIF.      26.0/16.0/26.0 MPH (20.0)         20.6/  27.3/  20.6
  LDV I/M PROGRAM STARTING  IN 1982, STRINGENCY LEVEL 30%, MECH.  TRAINING: NO
  I/M PROG. BENEFITS APPLY  ONLY TO MODEL YEARS 1951  THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO :
EXHAUST NOx:
LDV
1.00
10.05
1.50
LDT1
1.35
13.12
1.66
LDT2
1.97
18.98
2.15
HDG
5.91
93.40
4.55
(GM/MILE)
HDD
2.97
27.02
6.33
MC
0.40
3.46
0.18
ALL MODES
1.36
14.99
1.82
                               VEH. TYPE:   LDV   LDT1   LDT2   HDG   HDD   MC
 CAL. YEAR:  1995     TEMP:  75.0(F)         0.803/0.058/0.058/0.045/0.031/0.005
 REGION: CALIF.      26.0/16.0/26.0 MPH (20.0)          20.6/  27.3/  20.6
  LDV I/M PROGRAM STARTING  IN 1982, STRINGENCY LEVEL 30%, MECH.  TRAINING: NO
  I/M PROG.  BENEFITS APPLY  ONLY TO MODEL YEARS 1951  THROUGH  1999

                      COMPOSITE EMISSION FACTORS (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
0.86
8.79
1.49
LDT1
0.86
8.38
1.63
LDT2
1.07
11.30
2.01
HDG
3.13
52.57
3.02
HDD
2.83
27.00
4.39
MC
0.31
2.87
0.16
ALL MODES
1.03
11.41
1.68
                               VEH. TYPE:   LDV   LDT1   LDT2  HDG   HDD   MC
 CAL. YEAR: 1999     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: CALIF.      26.0/16.0/26.0 MPH (20.0)         20.6/  27.3/  20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECH.  TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951  THROUGH 1999
NON-METH HC:
EXHAUST  CO:
EXHAUST NOx:
       COMPOSITE EMISSION FACTORS (GM/MILE)
LDV      LDT1     LDT2     HDG      HDD       MC     ALL MODES
0.83     0.71     0.76     2.27     2.80     0.31       0.95
3.60     6.71     7.60    38.16    27.00     2.87      10.31
1.49     1.62     2.00     2.61     4.07     0.16       1.65

-------
                                    -31-
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1977     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: HI-ALT.     26.0/16.0/26.0 MPH (20.0)         20.6/  27.3/  20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%, MECU.  TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999

                      COMPOSITE EMISSION FACTORS (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
8.47
83.67
2.22
LDT1
9.37
89.22
2.19
LDT2
13.39
118.42
3.45
HDG
40.33
401.39
6.40
HDD
5.86
48.98
12.10
MC
13.96
48.62
0.08
ALL MODES
10.19
99.06
2.77
                               VEH. TYPE:   LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1980     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: HI-ALT.     26.0/16.0/26.0 MPH (20.0)         20.6/  27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%,  MECH.  TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
5.93
63.85
2.09
LDT1
7.18
75.59
1.85
LDT2
11.33
105.81
3.05
HDG
36.35
386.96
6.28
(GM/MILE)
HDD
5.93
45.73
12.16
MC
10.08
36.30
0.16
ALL MODES
7.70
80.80
2.62
                               VEH. TYPE:   LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1985     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
.REGION: HI-ALT.     26.0/16.0/26.0 MPH (20.0)         20.6/  27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%,  MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
COMPOSITE EMISSION FACTORS

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
2.17
20.87
1.62
LDT1
3.81
43.19
1.64
LDT2
5.88
56.74
2.18
HDG
20.78
275.33
5.94
(GM/MILE)
HDD
4.71
39.44
11.28
MC
2.70
10.49
0.17
ALL MODES
3.40
36.22
2.14
                               VEH. TYPE:  LDV   LDT1  LDT2  HDG   HDD   MC
 CAL. YEAR: 1990     TEMP: 75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: HI-ALT.     26.9/16.0/26.0 MPH (20.0)         20.6/ 27.3/ 20.6
  LDV I/M PROGRAM STARTING IN 1982, STRINGENCY LEVEL 30%,  MECH. TRAINING: NO
  I/M PROG. BENEFITS APPLY ONLY TO MODEL YEARS 1951 THROUGH 1999
NON-METH HC:
EXHAUST  CO:
EXHAUST NOx:
       COMPOSITE EMISSION FACTORS (GM/MILE)
LDV      LDT1     LDT2     HDG      HDD       MC     ALL MODES
1.05     1.76     2.70     9.50     3.18     0.51       1.63
9.90    18.89    25.88   119.80    29.65     3.58      16.88
1.55     1.26     1.56     3.72     4.72     0.15       1.72

-------
                                    -32-
                               VEH.  TYPE:   LDV   LDT1   LDT2   HDG   HDD   MC
 CAL. YEAR: 1995     TEMP:  75.0(F)        0.803/0.058/0.058/0.045/0.031/0.005
 REGION: HI-ALT.     26.0/16.0/26.0  MPH (20.0)         20.6/  27.3/  20.6
  LDV I/M PROGRAM STARTING  IN 1982,  STRINGENCY LEVEL 30%, MECH.  TRAINING: NO
  I/M PROG. BENEFITS APPLY  ONLY TO MODEL YEARS 1951  THROUGH  1999

                      COMPOSITE EMISSION FACTORS  (GM/MILE)

NON-METH HC:
EXHAUST CO:
EXHAUST NOx:
LDV
0.86
7.89
1.57
LDT1
1.03
11.17
1.09
LDT2
1.43
14.57
1.24
HDG
4.49
61.74
2.75
HDD
2.88
27.54
2.97
MC
0.31
2.88
0.16
•ALL MODES
1.12
11.47
1.61
                               VEH.  TYPE:   LDV   LDT1   LDT2   HDG   HDD   MC
 CAL. YEAR: 1999     TEMP:  75.0(F)         0.803/0.058/0.058/0.045/0.031/0.005
 REGION: HI-ALT.     26.0/16.0/26.0  MPH (20.0)         20.6/  27.3/  20.6
  LDV I/M PROGRAM STARTING  IN 1982,  STRINGENCY LEVEL 30%, MECH.  TRAINING: NO
  I/M PROG. BENEFITS APPLY  ONLY TO MODEL YEARS 1951  THROUGH  1999
                      COMPOSITE EMISSION FACTORS  (GM/MILE)
NON-METH HC:
EXHAUST  CO:
EXHAUST NOx:
LDV
0.82
7.58
1.57
LDT1
0.78
8.01
1.05
LDT2
0.86
9.20
1.13
 HDG
 2.55
40.86
 2.50
 HDD
 2.81
27.14
 2.69
 MC
0.31
2.87
0.16
ALL MODES
   0.96
   9.78
   1.58

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