-------
EPA-450/2-83-002
March 1983
Supplementary Guidelines For
Lead Implementation Plans
Updated Projections For Motor Vehicle
Lead Emissions
By
Penny M. Carey
U.S. Environmental Protection Agency
Office of Air, Noise and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
and
Office of Mobile Sources
Ann Arbor, Michigan 48105
-------
This report has been reviewed by the Office of Air Quality
Planning and Standards, US EPA, and approved for publication.
Mention of trade names or commercial products is not intended
to constitute endorsement or recommendation for use.
IX
-------
INTRODUCTION
The following material serves as an update to Revised Section
4.3, (Projecting Automotive Lead Emissions), in the
"Supplementary Guidelines for Lead Implementation Plans,"
U.S. EPA, EPA-450/2-78-038, Research Triangle Park, North
Carolina, August 1978. This document provides updated
projections for automotive lead emissions to be used by those
agencies developing State Implementation Plans for lead.
This document changes the basic equation for projecting
automotive lead emissions presented in Revised Section 4.3 of
the Supplementary Guidelines. The equation has been revised
to incorporate the effect of the new EPA lead phase-down
regulation, more recent on-road passenger car and light-duty
truck fuel economy data, an estimate of increased
dieselization of the light and heavy-duty fleet, more recent
projections of the percent of vehicles from 1975 and beyond
that require the use of nonleaded gasoline and the effects of
misfueling and discretionary fuel switching. Also discussed
are current expectations regarding heavy-duty vehicle
emission standards which affect use of leaded fuel.
The procedure herein should be used to project automotive
lead emissions instead of the procedure given in Revised
Section 4.3 of the Supplementary Guidelines.
-------
Those agencies developing State Implementation Plans for lead
should also note how the revision being made affects the EPA
guideline, "Development of an Example Control Strategy for
Lead" (EPA-450/2-79-002) . Specifically affected are
equations 2.3 (p. 14), 2.4 and 2.5 (p. 15) and the related
discussion, which are based on the previous procedure. The
new procedure should be used in lieu of that given on pp. 14
and 15 and related pages of the example control strategy for
lead.
This document was prepared by the Office of Mobile Sources in
response to the February 1983 request of the Office of Air
Quality Planning and Standards. Further revisions will be
made as needed as new information becomes available.
4.3 PROJECTING AUTOMOTIVE LEAD EMISSIONS
Lead emissions from mobile sources are calculated based on
the percentage of burned lead exhausted at different speeds,
the lead content of gasoline, vehicle fuel economy and the
model year mix of vehicles on the road. The lead content of
gasoline and the model year vehicle mix are a function of the
calendar year of interest. Vehicle fuel economy is averaged
for all vehicles of the same model year.
-------
4.3.1 Lead Emissions from Automobiles
4.3.1.1 Individual Roadways - For any given year subsequent
to 1974, the total population of automobiles on the road
consists of vehicles using either leaded or "nonleaded"
(i.e., required to contain less than 0.050 gram/gal, lead)
gasoline or diesel fuel. Diesel fuel is assumed to contain
quantities of lead that are insignificant compared to
gasoline fuel; therefore, only emissions from
gasoline-powered vehicles are considered. The emission rate
from automotive sources from an individual roadway (line
source) is calculated by the following equation:
a T
e
s
n,s C
s
n / m . F
Pb (0.92) + Pb (0.08) (0.55)
NL,n ^'J*> ' f"L,n v"-—'^---'y \ l K .
NL,i'
i=1975
c,i
PbL,n(°'929) + PbNL,n(0-°71) v
/ L
\Ec,i
i=n-19
PbNL,n(°-275)
i=1975
Ec,i
(1)
where:
e = emission rate for calendar year n and speed s
n, s
(g/road mile-day);
-------
ag = fraction of lead burned that is exhausted;
for roadways where steady cruise driving is
indicated (i.e., roadways that have a
relatively constant speed), a is available
s
from Figure 4.3-1 (nondimensional; expressed
as a percentage in Figure 4.3-1); for roadway
portions subject to full-throttle
acceleration (0-60 mph) use a = 10.0
o
(i.e., 1000%); for roadways where cyclic
driving is indicated (i.e., roadways that do
not have steady speed) use a = 0.75 (i.e.,
S
75%) ;
T = average daily traffic (vehicles/day);
C = speed-dependent fuel economy correction
o
factor based. on steady cruise or cyclic
driving; available from Table 4.3-1
(nondimensional) ;
PbNL n = lead content of "nonleaded" gasoline in
calendar year n from Table 4.3-2 (g/gal);
PbL n = average lead content of leaded gasoline in
calendar year n from Table 4.3-2 (g/gal);
-------
fraction of annual travel by model year i
light-duty vehicles from Table 4.3-3
(nondimensional, expressed as a decimal);
fraction of the model year i light-duty
vehicle fleet designed for use on nonleaded
gasoline from Table 4.3-4 (nondimensional,
expressed as a decimal) ;
FT . = fraction of the model year i light-duty
Li i 1
vehicle fleet designed for use on leaded
gasoline from Table 4.3-4 (nondimensional,
expressed as a decimal) ;
E . = city/highway combined on-road fuel economy
c r i
for model year i from Table 4.3-9
(vehicle-road mile/gal.).
To calculate the emission rate in units of
grams/meter-second, e can be corrected by dividing by
n f s
1.39 x 108.
Referring to equation (1) , the three terms within the
brackets give the grams lead emitted per vehicle-road mile (g
lead/vehicle-road mile) for calendar year n. The first term
within the brackets gives the g lead/vehicle-road mile
-------
emitted by light-duty catalyst-equipped vehicles whereas the
second and third terms within the brackets collectively give
the g lead/vehicle-road mile emitted by non-catalyst-equipped
vehicles. It should be noted that since 1975 a small number
of non-catalyst-equipped vehicles have been certified for use
on nonleaded gasoline. Since these vehicles constitute such
a small percentage of the total non-catalyst fleet, they will
not be considered. Instead, it will be assumed that all
non-catalyst-equipped vehicles can be operated on leaded
gasoline. Further discussion of selected variables used in
the equation follows.
Figure 4.3-2 compares steady cruise fuel economy and
generalized cyclic driving fuel economy to vehicle speed.
Figure 4.3-2 was generated using data from 1973, 1Q74 and
1975 model year vehicles. Using the cyclic driving fuel
economy at 32.7 miles per hour as the basis for comparison
(since this speed is the average speed for the EPA combined
city/highway fuel economy), fuel economy correction factors
(C ) for both steady cruise and cyclic driving can be
o
calculated at various speeds. These calculations have been
made and are presented in Table 4.3-1. Table 4.3-1 should be
used to interpolate C for those speeds not listed in Table
o
4.3-1. The fuel economy correction factor for cyclic driving
should be used for roadways that do not have steady speed.
(The determination of how much variation in speed constitutes
-------
cyclic driving is judgmental. Questionable cases should be
analyzed both ways.) Likewise, the fuel economy correction
factor for steady cruise driving should be used if free-flow,
steady speed driving is indicated (e.g., along a highway at a
relatively constant speed). The correction factors for
cyclic and steady cruise driving become similar at high
speeds as . the number of stops, accelerations and
decelerations during cyclic driving decrease.
The fraction of annual travel by model year i light-duty
vehicles (m.) can be found in the last column of Table
4.3-3. Values for m.^ in Table 4.3-3 are EPA's estimates of
the national values. Local values should be used where
available. The term, "m.", accounts collectively for all
light-duty vehicles - those using leaded, nonleaded, and
diesel fuels - in a given model year. The travel weighting
fractions were taken from the March 1981 EPA Report,
"Compilation of Air Pollutant Emission Factors: Highway
Mobile Sources" [EPA-460/3-81-005] and may be revised in the
future. It should be noted that the travel weighting
fractions in Table 4.3-3 reflect a January 1 evaluation date,
in contrast to the July 1 evaluation date used in Revised
Section 4.3.
The fractions of the model year i light-duty vehicle fleet
using nonleaded and leaded gasoline, FMT . and F .,
IN -U f 1 J_j f 1
-------
respectively, are given in Table 4.3-4. Values for FNL £
and FL ^ account for the increasing dieselization of the
light-duty vehicle fleet. Diesel-powered vehicles are
assumed to emit quantities of lead that are insignificant
compared to gasoline-powered vehicles; therefore, sales
fractions for diesel-powered vehicles are not included.
Latest sales projections for diesel-powered vehicles were
made by EPA based on data obtained from Jack Faucett
Associates, "The Impact of Light-Duty Diesel Particulate
Standards on the Level of Diesel Penetration in the
Light-Duty Vehicle and Light-Duty Truck Markets" (January
1983) , prepared under EPA contract. Estimates of the
percentages of gasoline vehicles requiring leaded and
nonleaded fuel were obtained from Energy and Environmental
Analysis, Inc., "Documentation for the New Highway Fuel
Consumption Model" (January 1982) .
The term, "miFNL j" in equation. (1) , then, is the
fraction of annual travel by model year i light-duty vehicles
designed for use on nonleaded gasoline; "m. F ." is the
i L, i
fraction of annual travel by model year i light-duty vehicles
designed for use on leaded gasoline.
An eight (8) percent misfueling rate for nonleaded
gasoline-powered vehicles was incorporated into equation
(1) . Misfueling is defined as the use of leaded gasoline in
vehicles certified for the use of nonleaded gasoline. This
-------
misfueling rate was used in the March 1981 EPA Report,
"Compilation of Air Pollutant Emission Factors: Highway
Mobile Sources" fEPA-460/3-81-005] and may be revised in the
future. The first term in equation (1) accounts for this
eight(8) percent of nonleaded gasoline-powered vehicles which
use leaded fuel even though use of nonleaded fuel in these
vehicles is required to prevent poisoning of the catalyst
and/or other effects of lead (e.g., combustion chamber
deposits, EGR deterioration) that result in these vehicles
not meeting the emission standards. An additional fraction,
0.55, is also included in the first term. This is an
estimate of the fraction of lead burned that is exhausted
from the catalyst of a misfueled, catalyst-equipped vehicle.
This estimate was obtained from Schneider, Eric, W. ,
"Detection of Leaded-Gasoline Usage in Catalyst-Equipped
Vehicles: A Gamma-Ray Transmission Gauge for Measuring
Catalytic Converter Lead Contamination", APCA Journal, Vol.
32, No. 5, May 1982. It should be considered a correction
factor to a for catalyst-equipped vehicles using leaded
o
fuel.
In addition to misfueling rates, discretionary fuel switching
rates for leaded gasoline-powered vehicles were incorporated
into equation (1) . Discretionary fuel switching is the use
of nonleaded gasoline in vehicles which normally operate on
leaded fuel. The discretionary fuel switching rates were
obtained from Energy and Environmental Analysis, Inc.,
-------
10
"Assessment of Current and Projected Future Trends in
Light-Duty Vehicle Fuel Switching" (June 1982) and are
applicable to automobiles and light-duty trucks with a gross
vehicle weight rating of less than 10,000 pounds.
Discretionary fuel switching rates for pre-1975 model year
vehicles designed for use on leaded fuel average 7.1 percent
while rates for post-1974 model year vehicles average
27.5 percent. The effect of discretionary fuel switching for
pre-1975 and post-1974 model year vehicles designed for use
on leaded fuel has been incorporated into the second and
third terms, respectively, in equation (1).
The city/highway combined on-road fuel economies, E ., for
c, i
model years 1970 to 1988 are given in Table 4.3-9. These
fuel economies were obtained from Energy and Environmental
Analysis, Inc., "The Highway Fuel Consumption Model - Eighth
Quarterly Report" (July 1982). EPA fuel economies were
discounted to on-road estimates by EEA with the use of
technology-specific shortfall relations.
4.3.1.2 Area Source Automotive Emissions - Equation (1) can
be modified to calculate automotive emissions as an area
source rather than as specific line sources. The emission
rate from automotive sources from an area source is
calculated by the following equation:
-------
n,s
11
V_
C
Pb
(0.92) (0.75) + PbT (0.08) (0.30)
n LI , n
\ n
') I
miFNL,i
i=1975
PbT (0.929) (0.75) +Pb1v7T (0.071) (0.75) 1 1974 /m.F,
•i-i, n WL, n
I
+ (Pb (0.725) (0.75) + PK (0 . 275) (0 . 75)
\ L,n NL,n i
i=n-19
n
i=1975
c.i
m.FT .N
i L, i
In equation (2), the term "T" was replaced by the term "V",
the vehicle miles traveled in the area on a daily, monthly or
greater time basis. When VMT data are used, the emission
rate, e , will be expressed in grams per day, month, etc.
n / s
(2)
The computation of area emissions precludes the use of Figure
4.3-1 for determining the percentage of burned lead
exhausted, a . Figure 4.3-1 is based primarily on tests of
s
lead emissions from vehicles operating at steady speeds over
short test periods. A value for a of 0.75 (i.e, 75
o
percent of the lead burned is exhausted) should be used for
non-catalyst-equipped, gasoline-powered vehicles operating on
leaded fuel when calculating automotive emissions as an area
source rather than as specific line sources. The 0.75 value
is based on tests which measured exhaust emissions under
cyclic driving conditions. For gasoline-powered vehicles
-------
12
with catalysts which are misfueled, a value for a of 0.30
should be used. The 0.30 value accounts for lead retention
by the catalyst, the oil, the combustion chamber and the rest
of the exhaust system*. The appropriate values for a have
S
been included within the brackets in equation (2) .
Finally, the speed dependent fuel economy correction factor,
C ., can be determined by either of two approaches. One
s, i
approach is to base C . on the average vehicle speed for
s, i
the area of concern. The average area vehicle speed should
be a weighted average based on average speeds and VMT data
for the various roadway classifications, such as limited
access (greater than 50 mph) , suburban roads (35 mph) and
urban streets (25 mph or less) . The other approach is to
determine C_ • and area emissions for each roadway
b , 1
classification (and average speed) separately, and then total
them. The latter approach is considered more accurate.
*For gasoline-powered vehicles with catalysts which are
misfueled, 45 percent of the lead burned is retained by the
catalyst and 25 percent of the lead burned is retained by the
oil, the combustion chamber and the rest of the exhaust
system; therefore 30 percent of the lead burned is exhausted
(1.00-0.45-0.25 = 0.30).
-------
13
4.3.2 Lead Emissions from Other Gasoline-Powered Vehicles
In addition to light-duty gasoline-powered vehicles, other
vehicles to consider include motorcycles, light-duty
gasoline-powered trucks and heavy-duty gasoline-powered
trucks.
Motorcycles are assumed to emit quantities of lead that are
insignificant compared to other gasoline-powered vehicles.
Light-duty gasoline-powered trucks have been separated into
two categories. Light-duty gasoline-powered trucks I have a
gross vehicle weight (GVW) rating of 6000 pounds or less.
Light-duty gasoline-powered trucks II have a GVW rating of
6001 to 8500 pounds. The emission rates for each light-duty
truck category are calculated using the same equations as for
automobiles. The only revision is that the starting point
for calculating emissions from nonleaded light-duty trucks II
is 1979 rather than 1975. Values for the variables used in
the equations are given in the following tables/figures:
Variable LPT 1 LPT2
as Figure 4.3-1 Figure 4.3-1
Cs Table 4.3-1 Table 4.3-1
PbNL n; PbL n Table 4.3-2 Table 4.3-2
mi ' ' Table 4.3-5 Table 4.3-7
FNL i? FL i Table 4.3-6 Table 4.3-8
Er ,- ' Table 4.3-9 Table 4.3-9
c, i
-------
14
Values for a and C are the same as those
s s
automobiles. In contrast, values for m., F^_ . F .
l NL, i L/i
and E . are different from those used for automobiles.
c, i
Values for m. in the last columns of Tables 4.3-5 and 4.3-7
are national values compiled by EPA in the March 1981 EPA
Report, "Compilation of Air Pollutant Emission Factors:
Highway Mobile Sources" [EPA-460/3-81-005] and may be revised
in the future. Local values for m.^ are preferable when
available.
Heavy-duty gasoline-powered trucks are assumed to burn leaded
gasoline until 1988. It is assumed that emission standards
effective in 1988 will result in the use of nonleaded fuel in
all heavy-duty gasoline-powered trucks. Also, their fuel
economy for any calendar year is assumed to be equal to 5.0
miles/gal. Therefore, the emission rate for heavy-duty
gasoline-powered trucks prior to 1988 is calculated by using
the following modification of equation (1):
•= rn pu
en s = s L*n (n <= 1988)
n'S 5.0
where T is the average daily traffic (heavy-duty gasoline
trucks/day).
-------
15
For 1988 and beyond, the following modification of equation
(3) should he used:
1987 n
en,s = 170 PbL,n V1 mi + PbNL,n V" mi
i=n-19 i=1988
(n2 1988)
(4)
Values for the variables used in equations (3) and (4) are
given in the following tables/figures:
Variable HDGT
as Figure 4.3-1
Cs Table 4.3-1
PbNL,n; pbL,n Table 4.3-2
mj_ Table 4.3-10
The effect of discretionary fuel switching has not been
incorporated in equations (3) and (4) due to the lack of data
on the current fuel purchase behavior of owners of heavy-duty
vehicles. Similarly, the effect of misfueling has not been
incorporated in equation (4) since this would apply to
heavy-duty vehicles not currently in production for which no
data exist. As new estimates for heavy-duty fuel economy and
new emission standards scenarios become available, equations
(3) and (4) will be revised accordingly. Values for ITK may
also be revised as new estimates become available.
-------
16
Fleet sales fractions for heavy-duty gasoline-powered trucks
I and II, projected to 1995, are given in Table 4.3-11.
Keavy-duty gasoline-powered trucks I have a gross vehicle
weight (GVW) rating of 8,501 to 26,000 pounds. Heavy-duty
gasoline-powered trucks II have a GVW rating greater than
26,000 pounds. The fleet sales fractions are decreasing with
model year, reflecting the increasing dieselization of the
heavy-duty fleet. These estimated fleet sales fractions can
be used when projecting T, the average daily traffic
(heavy-duty gasoline trucks/day), for future years.
Equations (3) and (4) can be modified to calculate emissions
as an area source rather than as specific line sources. The
term "T" should be replaced by the term "V", the vehicle
miles traveled by heavy-duty gasoline-powered trucxs in the
area on a daily, monthly or greater time basis. The fleet
sales fractions in Table 4.3-11 can be similarly used to
project area VMT for future years. When VMT data are used,
the emission rate, e , will be expressed in grams per
n / s
day, month, etc. Also, a , the fraction of burned lead
S
exhausted, should be 0.75.
4.3.3 Example Calculation of Automobile Lead Emissions
Problem: For a roadway where steady cruise driving is
indicated with a speed of 20 miles per hour and average daily
-------
17
traffic of 28,000 vehicles, calculate the lead emission rate
for the year 1988.
Solution: Use Equation (1):
e88,20
a20T
PbNL,88(CK92) + PbL,88(0-08)(°-55)
l NL,i
\ c,l
i=1975
^PbL,88(0-929) + PbNL,88<°-071y £ ( W~
i=1969
/ \ 1988 /m,F .-
PbL,88(°-725) + PbNL,88(0-275) ~~
/ i—i \ C , 1
i=1975
From Figure 4.3-1, for a cruise speed of 20 mph,
approximately 15.25 percent of the lead being burned is
emitted. Therefore, a2Q = 0.153.
The average daily traffic, T, is given as 28,000
vehicles/day. From Table 4.3-1, since steady cruise driving
is indicated, the speed-dependent fuel economy correction
factor for a speed of 20 mph, C2Q = 1.153.
From Table 4.3-2, the lead content of leaded gasoline in 1988
is 1.1 grams/gal., and the lead content of nonleaded gasoline
is 0.014 gram/gal.
-------
18
The summations,
1988 / T? x 1974 / TT 1988 m TP
/miFNL,iV ^ ( i L't\ and y / miFL,i
\c,i / L^ \c,i/ ^—' \c,i
i=1975 i=1969 i=1975
for vehicles burning nonleaded and leaded gasoline,
respectively, must now be calculated. First, the fraction of
annual travel, m., for each model year is determined by
setting the fraction for 1 year old vehicles (Table 4.3-3) at
the calendar year, n, for which lead emissions are being
estimated. For this example, n = 1Q88, therefore, miqo
-------
1988 /miFNL,i
i=1975
1974
I
i=1969
and,
1988
i=1975
;88,20
19
= 0.0381/vehicle-road miles/gal.
miFL,i
Ec,i .
0.0022/vehicle-road miles/gal,
= 0.0012/vehicle-road miles/gal
E .
Substituting the above results into Equation (1) ,
we obtain:
0.153x28xl0 vehicles/day
1 ™" " •— ^— ^ ____-*• 2\
1.153
( (0.014g/gal xO. 92+1. Ig/galxO. 08x0. 55) x 0.0381
veh-road mi/gal
+ ( (l.lg/gal x 0.929+0.014g/galxO.071) x 0.0022
veh-road mi/gal
+ ( (l.lg/gal x 0.0725+0.014g/galxO.275) x 0.0012
veh-road mi/gal
17.39 g/road-mile-day
In units of g/m-sec/ this becomes:
:88,20
17.39
1.39 x 10!
= 1.25 x 10~ g/mi-sec
-------
Q
H
e-i
CO
a
<
a
x
Q
W
03
fa
o
w
a
u
«
H
20
Figure 4.3-1
PERCENTAGE OF BURNED LEAD EXHAUSTED
vs.
VEHICLE CRUISE SPEED
TTT
50
MO
10
0
iH
,IM
111
Tl
n
tt
!>r
r i
I !
fi
~Z_
^
r X
f
£c
i i
4-
Tl
10
20
30
MO
VEHICLE CRUISE SPEED (MILES PER HOUR)
-------
21
Figure 4.3-2
;
FUEL ECONOMY AT VARIOUS SPEEDS*
SPEED, MPH
* Passenger Car Fuel Economy: EPA and Road, September 1980,
[EPA-460/3-80-010].
-------
22
Table 4.3-1
FUEL ECONOMY CORRECTION FACTORS AT VARIOUS SPEEDS, Cs
(Normalized to 32.7 miles/hour-cyclic driving)
Cs cs
Speed (mph) Cyclic Driving Steady Cruise
5 0.323 0.467
10 0.553 0.709
15 0.692 0.997
20 0.790 1.153
25 0.885 1.248
30 0.963 1.294
32.7 1.000 1.303
35 1.022 1.303
40 1.053 1.288
45 1.073 1.256
50 1.078 1.210
55 1.063 1.159
60 1.023 1.104
-------
23
Table 4.3-2
LEAD CONTENT OF GASOLINE
Leaded Gasoline* Nonleaded Gasoline
Year (g/gal) (g/gal)
1974 1.79
1975 1.82 0.014
1976 2.02 0.014
1977 2.03 0.014
1978 1.94 0.014
1979 1.85 0.014
1980 1.38 0.014
1981 1.15 0.014
1982 1.24 0.014
1983 1.14 0.014
1984 1.1 0.014
1985 1.1 0.014
1986 1.1 0.014
1987 1.1 0.014
1988 1.1 0.014
1989 1.1 0.014
1990 1.1 0.014
*1974-1982: Lead content based upon data submitted to EPA on
historical sales data for leaded gasoline and data indicating
the actual pooled average lead content. The value for
nonleaded gasoline is based on recent MVMA fuel surveys.
1983-1990: Lead content based upon requirements for average
lead content of leaded gasoline. During the first half of
1983, small refineries were subject to a pooled average lead
standard.
-------
24
Table 4.3-3
TRAVEL WEIGHTING FACTOR CALCULATION*
Light-Duty Vehicles
Vehicle
Age
(a)
Annual
Fraction
Total
Registration
(b)
Mileage
Accumulation
Rate
[(a) (b)/(SUM]
Fraction of
Annual LDV
Travel by
(a) (b) Model Year
m-
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20 +
0.024
0.101
0.092
0.071
0.092
0.103
0.089
0.071
0.066
0.059
0.048
0.035
0.030
0.023
0. 015
0.010
0.005
0.003
0.002
0.015
14400
14275
13775
13250
12675
12175
11650
11075
10575
10050
9475
8975
8450
7875
7375
6850
6275
5775
5275
4750
345.6
1441.8
1267.3
940.8
1166.1
1254.0
1036.9
786.3
697.9
5^2.9
454.8
314.1
253.5
181.1
110.6
68.5
31.4
17.3
10.6
71.3
0.031
0.131
0.115
0.085
0.106
0.114
0.094
0.071
0.063
0.054
0.041
0.028
0.023
0.016
0.010
0.006
0.003
0.002
0.001
0.006
SUM:
11042.8
*Compilation of Air Pollutant Emission Factors: Highway
Mobile Sources, March 1981, [EPA-460/3-81-005]. The travel
weighting fractions reflect a Januarv 1 evaluation date.
-------
25
Table 4.3-4
FLEET SALES FRACTIONS
Light-Duty Gasoline-Powered Vehicles
Model
Years
Pre-1975
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
WHERE:
Nonleaded Gasoline
Fraction of
LDV Fleet,
0.000
0.873
0.868
0.843
0.844
0.867
0.950
0.939
0.954
0.947
0.940
0.934
0.927
0.920
0.910
Leaded Gasoline
Fraction of
LDV Fleet, F_ .*
L, 1
1.000
0.127
0.132
0.157
0.126
0.093
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
FL,i
Estimated fraction of the LDV model year fleet
which use nonleaded gasoline.
Estimated fraction of the LDV model year fleet
which use leaded gasoline.
*Diesel and gasoline sales projections were made by EPA based
on data obtained from Jack Faucett Associates, "The Impact of
Light-Duty Diesel Particulate Standards on the Level of
Diesel Penetration in the Light-Duty Vehicle and Light-Duty
Truck Markets", January 1983.
Percentages of gasoline vehicles requiring leaded and
nonleaded fuel obtained from Energy and Environmental
Analysis, Inc. "Documentation for the New Highway Fuel
Consumption Model", January 1982.
-------
26
Table 4.3-5
TRAVEL WEIGHTING FACTOR CALCULATION*
Light-Duty Trucks I**
Vehicle
Age
1
2
3
4
5
6
1
8
9
10
11
12
13
14
15
16
17
18
19
20 +
(a)
Fraction
Total
Registration
0,
0.
0,
0.
0,
0.
0,
0,
0,
0.
0,
0.
0,
0,
0,
0.
0.
0.
0.
0.
032
094
085
061
091
099
076
060
044
048
046
033
035
033
026
021
015
Oil
010
013
(b)
Annual
Mileage
Accumulation
Rate
15600
15200
13625
12175
10925
9925
9200
8450
7875
7375
6900
6500
6125
5800
5425
5150
4925
4625
4400
4400
(a) (b)
499.2
1428.8
1158.1
742.7
994.2
982.6
699.2
507.0
346.5
354.0
317.4
214.5
214.4
191.4
141.1
108.2
73.9
50.9
44.0
57.2
[ (a) (b)/(SUM) ]
Fraction of
Annual LDT1
Travel by
Model Year, m-j
0.055
0.157
0.127
0.081
0.109
0.108
0.077
0.056
0.038
0.039
0.035
0.024
0.023
0.021
0. 015
0.012
0.008
0.006
0.005
0.006
SUM: 9125.3
*Compilation of Air Pollutant Emission Factors: Highway
Mobile Sources, March 1981, [EPA-460/3-81-005]. The travel
weighting fractions reflect a January 1 evaluation date.
**Light-duty trucks I have a gross vehicle weight (GVW)
rating of 6000 pounds or less.
-------
27
Table 4.3-6
FLEET SALES FRACTIONS
Light-Duty Gasoline-Powered Trucks I
Model
Years
Pre-1975
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
WHERE:
Nonleaded Gasoline
Fraction of
LDT1 Fleet, F^.*
0.000
0.812
0.912
0.^62
0.968
0.957
0.956
0.968
0.958
0.947
0.931
0.915
0.905
0.889
0.873
Leaded Gasoline
Fraction of
LDTlFleet, F_ .*
J-y/ 1
1.000
0.188
0.088
0.038
0.027
0.032
0.023
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
FL,i
Estimated fraction of the LDT1 model year fleet
which use nonleaded gasoline.
Estimated fraction of the LDT1 model year fleet
which use leaded gasoline.
*Diesel and gasoline sales projections were made by EPA based
on data obtained from Jack Faucett Associates, "The Impact of
Light-Duty Diesel Particulate Standards on the Level of
Diesel Penetration in the Light-Duty Vehicle and Light-Duty
Truck Markets", January 1983.
Percentages of gasoline vehicles requiring
nonleaded fuel obtained from Energy and
Analysis, Inc. "Documentation for the New
Consumption Model", January 1982.
leaded and
Environmental
Highway Fuel
-------
28
Table 4.3-7
TRAVEL WEIGHTING FACTOR CALCULATION*
Light-Duty Trucks II**
Vehicle
Age
(a)
Fraction
Total
Registration
(b)
Annual
Mileage
Accumulation
Rate
(a) (b)
[(a) (b)/(SUM)]
Fraction of
Annual LDT2
Travel by
Model Year, m-j
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20 +
0.082
0.207
0.155
0.097
0.057 '
0.056
0.039
0.030
0.023
0.020
0.017
0.011
0.010
0.008
0.005
0.006
0.004
0.003
0.003
0.004
15800
15400
13-800
12300
11125
10100
9300
8550
7975
7475
6975
6525
6225
5875
5425
5175
5000
4625
4400
4400
SUM:
1295.6
3187.8
2139.0
1193
634
565
362
256
183
149
118
71
62
47.0
27.1
31.1
20.0
13.9
13.2
17.6
10389.9
0
0,
0
0,
0,
0,
0.
0,
0,
0,
0,
0,
0,
0.
0,
0,
0,
0.
0,
0,
125
307
206
115
061
054
035
025
018
014
Oil
007
006
005
003
003
002
001
001
002
*Compilation of Air Pollutant Emission Factors: Highway
Mobile Sources, March 1981, [EPA-460/3-81-005]. The travel
weighting fractions reflect a January 1 evaluation date.
**Light-duty trucks II have a gross vehicle weight (GVW)
rating of 6001 to 8500 pounds.
-------
29
Table 4.3-8
FLEET SALES FRACTIONS
Light-Duty Gasoline-Powered Trucks II
Model
Years
Pre-1975
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
Nonleaded Gasoline
Fraction of
LDT2 Fleet, FNL ..*
0.000
0.000
0.000
0.000
0.000
0.975
0.950
0.925
0.901
0.876
0.838
0.801
0.776
0.739
0.702
Leaded Gasoline
Fraction of
LDT2 Fleet, FT .*
j-if i
1.000
1.000
1.000
1.000
0.988
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
WHERE:
FNL,i
FL,i
Estimated fraction of the LDT2 model year fleet
which use nonleaded gasoline.
Estimated fraction of the LDT2 model year fleet
which use leaded gasoline.
*Diesel and gasoline sales projections were made by EPA based
on data obtained from Jack Faucett Associates, "The Impact of
Light-Duty Diesel Particulate Standards on the Level of
Diesel Penetration in the Light-Duty Vehicle and Light-Duty
Truck Markets", January 1983.
Percentages of gasoline vehicles requiring leaded and
nonleaded fuel obtained from Energy and Environmental
Analysis, Inc., "Documentation for the New Highway Fuel
Consumption Model", January 1982.
-------
30
Table 4.3-9
CITY/HIGHWAY COMBINED ON-ROAD FUEL ECONOMY*
(miles/gallon)
Model Year
Pre-1970
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
Fuel Economy, En f j_
LDV LDT1 LDT2
13.9
13.9
13.2
13.1
12.9
12.6
13.9
14.9
15.6
16.7
18.5
19-6
21.8
23.3
24.6
26.0
27.4
28.8
30.2
31.6
10.6
10.6
10.4
10.2
9-9
9.6
12.0
12.6
13.8
14.3
15.2
16.3
18.1
18.4
18.9
19.5
20.2
21.1
22.0
22.9
7.9
7.9
7.7
7.4
7.0
6.9
8.8
9.7
9.4
9.6
9.8
11.5
13.3
13.8
14.3
14.9
15.4
16.0
16.6
17.2
*Fuel economies for model years 1980-1988 were obtaine'd from
Energy and Environmental Analysis, Inc., "The Highway Fuel
Consumption Model - Eighth Quarterly Report" (U.S. DOE
Contract Number DE-AC01-79PE-70032, Task No. 13, July 1,
1982) . Fuel economies for model years 1970-1979 were
obtained from Robert Dulla, EEA.
-------
31
Table 4.3-10
TRAVEL WEIGHTING FACTOR CALCULATION*
Heavy-Duty Gasoline-Powered Trucks
(a)
Fraction
Vehicle
Age
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20 +
Total
Registration
0.0
0.114
0.097
0.073
0.086
0.088
0.070
0.053
0.041
0.044
0.040
0.031
0.030
0.026
0.021
0.018
0.013
0.009
0.008
0.010
(b)
Annual
Mileage
Accumulation
Rate
SUM:
(a) (b)
11805.5
[(a) (b)/(SUM)]
Fraction of
Annual HDGT
Travel by
Model Year, m-j
0
21000
18900
17200
15500
14100
12600
11300
10300
9400
8600
8000
7300
6700
6300
5900
5500
5200
5000
5000
0.0
2394.0
1833.3
1255.6
1333.0
1240.8
882.0
598.9
422.3
413.6
344.0
248.0
219.0
174.2
132.3
106.2
71.5
46.8
40.0
50.0
0.000
0.203
0.155
0.106
0.113
0.105
0.075
0.051
0.036
0.035
0.029
0.021
0.019
0.015
0.011
0.009
0.006
0.004
0.003
0.004
*Compilation of Air Pollutant Emission Factors: Highway
Mobile Sources, March 1981, [EPA-460/3-81-005] . The travel
weighting fractions reflect a January 1 evaluation date.
**Heavy-duty trucks have a gross vehicle weight (GVW) rating
greater than 8,501 pounds.
-------
32
Table 4.3-11
FLEET SALES FRACTIONS
Heavy-Duty Gasoline-Powered Trucks I and II*
Model Gasoline Gasoline
Years Fraction of Fraction of
HDT1 Fleet** HDT2 Fleet**
Pre-1977 0.982 0.136
1977 0.970 0.108
1978 0.968 0.111
1979 0.959 0.101
1980 0.950 0.092
1981 0.910 0.082
1982 0.870 0.072
1983 0.813 0.063
1984 0.755 0.053
1985 0.698 0.043
1986 0.681 0.040
1987 0.665 0.038
1988 0.648 0.035
1989 0.632 0.033
1990 0.615 0.030
1991 0.598 0.027
1992 0.582 0.025
1993 0.565 0.022
1994 0.549 0.020
1995 0.532 0.017
*Heavy-duty trucks I have a gross vehicle weight (GVW) rating
of 8,501 to 26,000 pounds. Heavy-duty trucks II have a gross
vehicle weight (GVW) rating greater than 26,000 pounds.
**The estimated fractions of the HDT1 and HDT2 model year
fleets which are gasoline-powered are based on Data Resources
Inc. sales projections for heavy-duty diesel vehicles, U.S.
Long Term Review, Summer 1982.
-------
33
Table 4.3-12
EXAMPLE CALCULATIONS
Light-Duty Gasoline Vehicle Lead
Emission Rate for the Year 1988
(1975-1988) (1969-1974) (1975-1988)
Model
Year
1988
1987
1986
1985
1984
1983
1982
1981
1980
1979
1978
1977
1976
1975
1974
1973
1972
1971
1970
pre-
1970
Age
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20+
m.
0.031
0.131
0.115
0.085
0.106
0.114
0.094
0.071
0.063
0.054
0.041
0.028
0.023
0.016
0.010
0.006
0.003
0.002
0.001
0.006
F
NL,i
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.910
.920
.927
.934
.940
.947
.954
.939
.950
.867
.844
.843
.868
.873
-
—
—
—
-
-
FL,i
0
0
0
0
0
1
1
1
1
1
1
-
-
.093
.126
.157
.132
.127
.000
.000
.000
.000
.000
.000
Ec,i
31.6
30.2
28.8
27.4
26.0
24.6
23.3
21.8
19.6
18.5
16.7
15.6
14.9
13.9
12.6
12.9
13.1
13.2
13.9
13.9
'
(
0
0
0
0
0
0
0
0
0
0
0
0
0
0
i NLf i \
Ec,i /
.0009
.0040
.0037
.0029
.0038
.0044
.0038
.0031
.0031
.0025
.0021
.0015
.0013
.0010
-
-
-
-
-
-
. r
1 (•
0
0
0
0
0
0
i L, i \
Bc,i /
.0008
.0005
.0002
.0002
.0001
.0004
0.0003
0.0003
0.0003
0.0002
0.0001
0.0381
0.0022
0.0012
-------
TECHNICAL REPORT DATA
(Please read instructions on the reverse before completing]
1. REPORT NO.
EPA-450/2-83-OQ2
3. RECIPIENT'S ACCESSIOWNO.
. TITLE AND SUBTITLE
Supplementary Guidelines for Lead Implemen-
tation Plans -- Updated Projections for
Automobile Lead Emissions
5. REPORT DATE
March 1983
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO,
Penny M. Carey
9. PERFORMING ORGANIZATION NAME AND ADDRESS
U.-S, Environmental Protection Agency
Office of Air, uoise, and Radiation
Office of Mobile Sources
Ann Arbor, MI 48105
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
13. TYPE OF REPORT AND PERIOD COVERED
Revision - Final
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This guidance is an update to Revised Section 4.3 (Projecting,
Automotive Lead Emissions), in the "Supplementary Guidelines for Lead
Implementation Plans," U.S. EPA, EPA-450/2-78-033,, Research Triangle
Park, North Carolina, August 1978. The basic equation for projecting
automotive lead emissions has been revised to incorporate the effect
of the new EPA lead phase-down regulation, more recent on-road
passenger car and light-duty truck fuel economy data, an estimate of
increased dieselization of the light and heavy-duty fleet, the effect
of misfueling, and more recent projections of the percent of vehicles
from 1975 and beyond that require the use of nonleaded gasoline. Also
discussed are current expectations regarding heavy-duty vehicle
emission standards which affect use of leaded fuel.
17.
KEY WORDS AND DOCUMENT ANALYSIS
a.
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Air Pollution
Atmosphere contamination control
Lead
State implementation
plan
National ambient air
quality standard
13-B
13. DISTRIBUTION STATEMENT
Release unlimited
19. SECURITY CLASS (This Report)
Unclassified
21. NO. OF PAGES
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 <9-73)
-------
INSTRUCTIONS
1. REPORT NUMBER
Insert the EPA report number as it appears on the cover of the publication.
2. LEAVE BLANK
3. RECIPIENTS ACCESSION NUMBER
Reserved for use by each report recipient.
4. TITLE AND SUBTITLE
Title should indicate clearly and briefly the subject coverage of the report, and be displayed prominently. Set subtitle, if used, in smaller
type or otherwise subordinate it to main title. When a report is prepared in more than one volume, repeat the primary title, add volume
number and include subtitle for the specific title.
5. REPORT DATE
Each report shall cany a date indicating at least month and year. Indicate the basis on which it was selected (e.g., date of issue, date of
approval, date of preparation, etc.j.
6. PERFORMING ORGANIZATION CODE
Leave blank.
7. AUTHOR(S)
Give name(s) in conventional order (John R. Doe, J. Robert Doe, ere.}. List author's affiliation if it differs from the performing organi-
zation.
8. PERFORMING ORGANIZATION REPORT NUMBER
Insert if performing organization wishes to assign this number.
9. PERFORMINaORGANIZATION NAME AND ADDRESS
Give name, street, city, state, and ZIP code. List no more than two levels of an organizational hirearchy.
10. PROGRAM ELEMENT NUMBER
Use the program element number under which the report was prepared. Subordinate numbers may be included in parentheses.
11. CONTRACT/GRANT NUMBER
Insert contract or grant number under which report was prepared.
12. SPONSORING AGENCY NAME AND ADDRESS
Include ZIP code.
13. TYPE OF REPORT AND PERIOD COVERED
Indicate interim final, etc., and if applicable, dates covered.
14. SPONSORING AGENCY CODE
Leave blank.
15. SUPPLEMENTARY NOTES
Enter information not included elsewhere but useful, such as: Prepared in cooperation with, Translation of, Presented at conference of,
To be published in, Supersedes, Supplements, etc.
16. ABSTRACT
Include a brief (200 words or less) factual summary of the most significant information contained in the report. If the report contains a
significant bibliography or literature survey, mention it here.
17. KEY WORDS AND DOCUMENT ANALYSIS ,
(a) DESCRIPTORS - Select from the Thesaurus of Engineering and Scientific Terms the proper authorized terms that identify the major
concept of the research and are sufficiently specific and precise to be used as index entries for cataloging.
(b) IDENTIFIERS AND OPEN-ENDED TERMS - Use identifiers for project names, code names, equipment designators, etc. Use open-
ended terms written in descriptor form for those subjects for which- no descriptor exists.
(c) COSATI FIELD GROUP - Field and group assignments are to be taken from the 1965 COS ATI Subject Category List. Since the ma-
jority of documents are multidisciplinary in nature, the Primary Field/Group assignment(s) will be specific discipline, area of human
endeavor, or type of physical object. The application(s) will be cross-referenced with secondary Fieid/Group assignments thai will follow
the primary posting(s).
18. DISTRIBUTION STATEMENT
Denote reusability to the public or limitation for reasons other than security for example "Release Unlimited." Cite any availability to
the public, with address and price.
19. & 20. SECURITY CLASSIFICATION
DO NOT submit classified reports to the National Technical Information service.
21. NUMBER OF PAGES
Insert the total number of pages, including this one and unnumbered pages, but exclude distribution list, if any.
22. PRICE
Insert the price set by the National Technical Information Service or the Government Printing Office, if known.
EPA Form 2220-1 (3-73) (Reverse)
------- |