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Particle Mass Emission Rates from Current-
Technology, Light-Duty Gasoline Vehicles
Richard E. Chase a , Gary J. Duszkiewicz a , Trescott E. Jensen a , Desmonia Lewis a
E. John Schlaps b , Arnie T. Weibel b , Steven Cadle c & Patricia Mulawa c
a Ford Research Laboratory , Dearborn , Michigan , USA
,
b DaimlerChrysler Corporation , Auburn Hills , Michigan , USA
c General Motors Research and Development , Warren , Michigan
Published online: 27 Dec 2011.
To cite this article: Richard E. Chase , Gary J. Duszkiewicz , Trescott E. Jensen , Desmonia Lewis , E. John
Schlaps , Arnie T. Weibel , Steven Cadle & Patricia Mulawa (2000) Particle Mass Emission Rates from Current-
Technology, Light-Duty Gasoline Vehicles, Journal of the Air & Waste Management Association, 50:6, 930-935, DOI:
10.1080/10473289.2000.10464138
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Chase et al.
TECHNICAL PAPER
ISSN 1047-3289 J. Air & Waste Manage. Assoc. 50:930-935
Copyright 2000 Air & Waste Management Association
Particle Mass Emission Rates from Current-Technology,
Light-Duty Gasoline Vehicles
Richard E. Chase, Gary J. Duszkiewicz, Trescott E. Jensen, and Desmonia Lewis
Ford Research Laboratory, Dearborn, Michigan
E. John Schlaps and Arnie T. Weibel
DaimlerChrysler Corporation, Auburn Hills, Michigan
Steven Cadle and Patricia Mulawa
General Motors Research and Development, Warren, Michigan
ABSTRACT
INTRODUCTION
Now that the U.S. Environmental Protection Agency has pro-
mulgated new National Ambient Air Quality Standards for
PM2.5, work will begin on generating the data required to de-
termine the sources of ambient PM2.5 and the magnitude of
their contributions to air pollution. This paper summarizes
the results of an Environmental Research Consortium pro-
gram, carried out under the auspices of the U.S. Council for
Automotive Research. The program focused on particulate
matter (PM) emissions from representative, current-technol-
ogy, light-duty gasoline vehicles produced by DaimlerChrysler
Corp., Ford Motor Co., and General Motors Corp. The ve-
hicles, for the most part taken from the manufacturer’s certi-
fication and durability fleets, were dynamometer-tested using
the three-phase Federal Test Procedure in the companies’ labo-
ratories. The test fleet was made up of a mixture of both low-
mileage (2K–35K miles) and high-mileage (60K–150K miles)
cars, vans, sport utility vehicles, and light trucks. For each
vehicle tested, PM emissions were accumulated over 4 cold-
start tests, which were run on successive days. PM emission
rates from the entire fleet (22 vehicles total) averaged less than
2 mg/mile. All 18 vehicles tested using California Phase 2
reformulated gasoline had PM emission rates less than 2 mg/
mile at both low and high mileages.
Previous data for PM10 suggest th at m otor veh icles con -
tribute a sign ifican t, th ough n ot th e m ajor, fraction of
th e PM10 source.2 Recen t studies h ave dem on strated th at
in -use veh icles can con tribute con siderably to PM10 con -
cen tration s (103 veh icles tested averaged 138 m g/m ile,
an d sm okin g veh icles em itted 395 m g/m ile).3 Alth ough
th e regulated m axim um level of particulate m atter (PM)
em ission s from gasolin e-fueled veh icles is 80 m g/m ile, ve-
h icles tested durin g th e past decade h ave em itted m uch
less. A study of the effects of m ethylcyclopentadienyl m an-
gan ese tricarbon yl (MMT) on veh icle em ission s4 from th e
early 1990s also reported PM em ission s usin g base fuel at
less th an 5 m g/m ile. A study of both n orm al an d m al-
fun ction in g veh icles5 usin g an in dustry average fuel
sh owed th at th e n orm al veh icle PM em ission rate was 6
m g/m ile, wh ile th e m alfun ction in g veh icle produced PM
em ission rates between 25 and 40 m g/m ile. A sim ilar study
usin g Californ ia reform ulated fuel6 foun d PM em ission s
for a 1990 m odel year veh icle to be in th e ran ge of 2–6
m g/m ile for both n orm al veh icle operation an d selected
m alfun ction in g m odes.
However, to accurately access th e con tribution of cur-
ren t tech n ology veh icles to PM2.5, n ew studies of th eir PM
em ission s are required. Th e im portan ce of reexam in in g
PM em ission s is un derscored by th e fact th at th e em is-
sion s m odel, PART5, uses a PM em ission rate of about 15
m g/m ile in its calculation s, a value con siderably h igh er
th an th ose for n orm ally operatin g veh icles, even in th e
early 1990s.
IMPLICATIONS
Motor vehicles are a source of PM. The significance of
vehicles as contributors to urban environmental particle
concentrations needs to be evaluated from both environ-
mental and vehicle measurement data. This report pro-
vides particle emissions data for current-technology
(1994–1998) gasoline vehicles at both low and high mile-
ages. Particle emission rates for both low- and high-
mileage vehicles, using California reformulated fuel, are
about 2 mg/mile.
Th is paper sum m arizes th e results of an En viron m en -
tal Research Con sortium (ERC) program , carried out un -
der th e auspices of th e U.S. Coun cil for Autom otive
Research (USCAR), to m easure particle m ass em ission rates
from representative, current-technology, light-duty gasolin e
930 Journal of the Air & Waste Management Association
Volume 50 June 2000

Chase et al.
veh icles produced by Daim lerCh rysler Corp., Ford Motor
Co., an d Gen eral Motors Corp.
(38 °C), filtered air. Vehicle exhaust was introduced along
the tunnel axis in the direction of flow at the sam e loca-
tion as a m ixing baffle. The tunnel was designed to operate
in the turbulent flow regim e, and the PM sam pling section
was located m ore than 10 tunnel diam eters downstream
to allow m ixing of the exhaust and dilution air. Gaseous
sam pling was conducted an additional 10 tunnel diam -
eters beyond the PM sam pling location. The tim e between
entrance to the tunnel and the filter probe was 1.3 sec, and
that between the probe tip and the filter was 0.1 sec. The
flow rates of the dilution air and of the diluted exhaust
were m easured with subsonic venturis (SAOs).
EXP ERIMENTAL
Th e m easurem en ts of PM an d gaseous em ission s were
m ade at chassis dynam om eter facilities at each of the three
participating com panies. Em issions sam pling system s were
gen erally sim ilar. For exam ple, th e Veh icle Em ission s Re-
search Laboratory (VERL) facility at th e Ford Research
Laboratory is a ch assis rolls dyn am om eter research facil-
ity. Its two-fold m ission is to m easure low-level em ission s
with low variability, an d to develop em ission s in strum en -
tation an d m eth odologies applicable to a wide variety of
sam plin g an d speciation tech n iques for research studies.
Th e VERL h as a four-ben ch an alyzer system for catalyst
efficien cy m easurem en ts, as well as th e usual bag m ea-
surem en ts. It is equipped with a 48-in . AC electric dyn a-
m om eter. Th is facility h as been described in detail
elsewhere.7,8 For PM studies, a dual dilution tunnel actively
con trols th e flow, usin g two sm ooth approach orifice
(SAO) units to m aintain constant flow during a test. The
dilution tunnels used at Daim lerChrysler and GM were of
conventional design (blower and venturi configuration).
PM m easurem en ts at th e VERL were all obtain ed with
the lower dilution tunnel, dedicated to low-em itting, non-
diesel veh icles. Veh icle exh aust was tran sferred to th e tun -
n el th rough a h eated, corrugated, stain less steel h ose 9.2
cm in diam eter an d 5.8 m lon g. In itial work at on e facil-
ity, usin g a silicon e rubber h ose, resulted in h igh artifact-
produced PM em ission rates, an d th e silicon e h ose was
replaced with stain less steel. Addition al discussion of
sources of artifact form ation in PM em ission s m easure-
m en t h as been reported.9 No silicon e rubber m aterial was
used in th e sam plin g system s at th e th ree facilities for th e
data reported in th is study.
The tunnel was operated as a constant volum e sam -
pler; that is, the flow rate for the diluted exhaust was held
con stan t at 350 scfm for th ese tests u sin g a d u al
servosystem , which controls the total flow using a variable
speed outlet blower and controls the tunnel pressure via a
variable speed inlet blower. The tunnel pressure was held
to within 2.5 cm of water of atm ospheric pressure during a
test. The dilution ratio ranged from 4:1 for the m axim um
exhaust flow of the large displacem ent engines to 70:1 for
the sm allest engines at idle. The tem perature of the diluted
exhaust in the tunnel ranged from 38 to 50 °C, and the
hum idity ranged from a dew point of –9 to 24 °C.
PM sam plin g at VERL was accom plish ed th rough
probes th at pen etrated th e tun n el wall at an an gle of on ly
20° to m in im ize im pact losses. Th e filter h ousin g was
m oun ted about 30 cm from th e probe tip durin g collec-
tion . Th e probe tips en ded in a flared taper, with an in -
side diam eter of 1.9 cm , an d were m ade of stain less steel.
Flow values in th e five PM circuits were con trolled by a
servosystem an d were set to be isokin etic, so th at th e lin -
ear velocity in to th e probe open in g was equal to th e lin -
ear velocity of th e diluted exh aust past th e probe tip an d
th rough th e tun n el.
Th e tran sit tim e of th e exh aust, in th e tran sfer pipe,
ran ged from about 1 to 16 sec. Th e lon gest tran sit tim e,
16 sec, was for th e sm allest displacem en t en gin es at idle
an d was of sh ort duration in th e total test. Possible aggre-
gation of particles with in th e tran sfer pipe at lon g tran sit
tim es would be an advan tage for filter efficien cy an d par-
ticle reten tion for th e total m ass m easurem en ts, but th e
expected sm all n um ber of particles m ade aggregation
un likely. Loss to th e walls of th e tran sfer h ose at cold start
an d idle was expected to be partly reversible wh ere th e
PM could be resuspended later at higher driving cycle tem -
perature an d flow rates.
In all of th e facilities, PM was accum ulated on 47 m m
diam eter Teflo10 filters with a pore size of 2 µm . Such fil-
ters h ave h igh in itial reten tion efficien cy, 99.99%, as re-
ported by th e m an ufacturer.11 High efficien cy is required
for th ese m easurem en ts because such sm all m asses are
accum ulated th at it is critical to retain as m uch sam ple as
possible. Sign ifican t loadin g does n ot occur, an d tradi-
tion al filters (T60A20) used for diesel testin g, wh ich rely
on particle loadin g for in creasin g th eir efficien cy, can n ot
be used. Use of Teflo filters results in a large pressure drop
over th e filter (7.4 kPa or about 1 psi). Because of th e h igh
filter efficien cy an d th e pressure drop, on ly a sin gle filter
was used for sam plin g. Th ese Teflo filters also h ave th e
advan tage of con tain in g a h ard outer polym eth ylpen ten e
support rin g, wh ich perm its easy h an dlin g an d m in im izes
loss of filter m aterial to th e filter h older seals.
The tunnel was m odular, constructed of sections of
30.4 cm diam eter stainless steel tube, joined with gaskets
and flanges. The interior of the tunnel was electropolished,
and recesses were m inim ized to m itigate contam ination.
Dilution air was conditioned in a special preparation sys-
tem to provide low-hum idity (–9 °C dew point), heated
Separate filters were collected for each ph ase of th e
th ree-ph ase Federal Test Procedure (FTP). To accum ulate
Volume 50 June 2000
Journal of the Air & Waste Management Association 931

Chase et al.
sufficien t PM to perm it accurate weigh in g, particles were
collected on each filter for four FTP tests. Filters were equili-
brated with th e balan ce room h um idity for at least 1 h r
an d th en pre- an d post-weigh ed on a m icrobalan ce with
a resolution of 1 µg. Referen ce filters were weigh ed with
th e PM filters to en sure close en viron m en tal con trol an d
consistent m icrobalance perform ance. The estim ated lim it
of detection for PM em ission s for each filter was approxi-
m ately 0.1 m g/m ile.
low-mileage fleet and about the five cars and four trucks of
the high-mileage fleet. In Table 1, vans, sport utility vehicles,
and light trucks are all classified as trucks.
Th e fuel used with m ost of th e veh icles tested was
reform ulated Californ ia Ph ase 2 reform ulated gasolin e
(RFG). A few of th e trucks were tested usin g EPA certifica-
tion fuel. Gen eral fuel properties are given in Table 2. As
m en tion ed above, veh icles were tested usin g th e stan dard
EPA th ree-ph ase FTP, for wh ich bag sam ples were collected
an d an alyzed. Veh icles were precon dition ed by drivin g
th e sam e FTP test on th e first day, followed by testin g on
four successive days durin g wh ich PM was accum ulated
on th e filters. Veh icles were soaked overn igh t in a tem -
perature- an d h um idity-con trolled en viron m en t an d were
n ot driven between tests.
Vehicles for this study were chosen to be late-model,
light-duty gasoline cars, vans, sport utility vehicles, and light
trucks with high sales volume. The vehicles used fell into
two different mileage ranges: low mileage, typically below
8000 miles, and high mileage, typically about 100,000 miles.
Most of the 13 low-mileage vehicles came from certification
fleets of DaimlerChrysler, Ford, or General Motors. The high-
mileage vehicles were more difficult to obtain and came from
several different programs. Table 1 presents more detailed
in form ation about th e six cars an d seven trucks of th e
RESULTS AND DISCUSSION
Tests were perform ed durin g 1996 an d 1997 in facilities
at Daim lerCh rysler, Ford, an d Gen eral Motors. Tables 3
Table 1. List of vehicles tested and their characteristics.
Vehicle ID
Model Year
Displacement (liters)
Fuel Injection
Test Fuel
Odometer (miles)
Low-Mileage Cars
A
B
C
D
Q
R
1996
1996
1995
1994
1996
1996
4.6
3.1
3.8
2.3
3.0
1.9
SFI
SFI
SFI
PFI
SFI
SFI
RFG
RFG
RFG
RFG
RFG
RFG
<6,000
6,614
15,131
5,327
5,346
5,656
Low-Mileage Trucks
E
F
G
H
I
1997
1996
1998
1997
1995
1994
1996
4.2
3.8
5.2
4.0
3.8
3.1
4.0
SFI
SFI-SPI
SFI
EPA Certification Fuel
EPA Certification Fuel
EPA Certification Fuel
EPA Certification Fuel
RFG
<8,000
<8,000
5,933
SFI
2,514
SFI
10,901
36,201
5,461
J
EFI
RFG
S
SFI
RFG
High-Mileage Cars
K
L
1994
1994
1994
1996
1998
3.8
5.7
3.8
3.0
4.6
SFI
PFI
SFI
SFI
SFI
RFG
RFG
RFG
RFG
RFG
89,992
89,978
M
T
V
100,000
100,197
104,043
High-Mileage Trucks
N
O
P
U
1997
1998
1995
1995
4.0
5.2
4.3
3.0
SFI
SFI
CPI
SFI
RFG
RFG
RFG
RFG
99,535
119,168
61,800
150,511
CPI = central point (fuel) injection, RFG = reformulated gasoline, EFI = electronic fuel injection, PFI = port fuel injection, SFI = sequential fuel injection, and SPI = split port injection.
932 Journal of the Air & Waste Management Association
Volume 50 June 2000

Chase et al.
Table 2. Fuel composition.
EPA Certification Fuel
Th e gaseous em ission s results dem on strate th at th ese ve-
h icles are n orm al operatin g sam ples of each m odel.
PM em ission s ran ged from 0.23 to 0.86 m g/m ile for
th e n in e test series in volvin g th e six low m ileage cars, as
sh own in Table 3. Th e m ean value was 0.60 m g/m ile, an d
th e stan dard deviation for th e six cars was 0.17 m g/m ile.
0.60 m g/m ile was lower th an results reported for earlier
m odel veh icles2-5 an d was substan tially below th e regu-
lated level of 80 m g/m ile. The phase-by-phase results show
th at ph ase 1 dom in ated PM em ission s, m uch as it typi-
cally does for HC, CO, an d NOx. However, exception s
occurred durin g th e first test week for veh icle B an d th e
secon d test week for veh icle D. Note th at th e variability
of th e PM m easurem en ts was con siderable at th ese low
em ission rates. An an alysis of th e filter weigh in g process
sh owed th e error to be equivalen t to about 0.1 m g/m ile.
Th e variability of repeated m easurem en ts for veh icles B,
D, E, G, H, an d I was 0.35 m g/m ile, determ in ed by aver-
agin g th e differen ces. Th e em ission s for ph ase 2 for th e
two exception s (B & D) exceeded th ose for ph ase 1 by less
th an 0.35 m g/m ile, suggestin g th at variability m ay ac-
coun t for th e reversal.
RFG
Paraffins
Olefins
Aromatics
MTBE
55%
<1%
44%
0%
59%
2%
26%
13%
100%
Total
100%
an d 4 sum m arize th e gaseous an d PM m easurem en ts for
both cars an d trucks an d for low an d h igh m ileage, re-
spectively. Note th at all th e em ission s are expressed in
m g/m ile. Below each section , th e m ean value for each of
th e em ission s an d th e stan dard deviation for th e series of
veh icles tested (with weigh tin g don e by veh icle, n ot by
test) are given . For exam ple, th e m ean values for cars in
Table 3 for total h ydrocarbon (HC), CO, an d NOx are 127,
1284, an d 178 m g/m ile, respectively. Th ese n um bers are
all lower th an th ose called for by th e 1990 Clean Air Act
Am en dm en ts12 for passen ger cars, n am ely, 410 m g/m ile
for HC, 3400 m g/m ile for CO, an d 400 m g/m ile for NOx.
Table 3. Gaseous and PM emissions results for low-mileage vehicles.
Vehicle ID
Weighted Gaseous Emissions (mg/mile)
CO
PM Emissions (mg/mile)
HC
NO
Phase 1
Phase 2
Phase 3
Weighted
x
Cars
A
85
200
210
140
130
110
140
73
910
60
0.89
0.68
0.76
1.30
0.71
0.68
1.77
0.43
0.97
0.44
0.67
0.84
0.48
0.60
0.25
0.96
0.36
0.12
0.50
0.20
0.54
1.05
0.30
0.45
0.60
0.30
0.64
0.30
0.51
0.13
0.68
0.86
0.49
0.71
0.44
0.72
0.73
0.23
0.60
0.17
B
1720
1740
1250
1490
1660
1160
1077
1284
284
370
380
270
140
150
140
80
B
C
D
D
Q
R
Mean
Std dev
127
43
178
111
Trucks
E
115
115
107
290
340
140
160
170
150
290
92
1001
1001
868
43
7.55
6.31
4.56
3.20
2.29
1.85
1.60
0.75
1.50
1.44
0.90
2.78
2.06
0.15
0.11
0.17
2.06
1.61
1.88
1.11
0.60
0.24
0.61
0.10
0.68
0.65
1.29
1.65
0.62
1.99
1.95
2.66
2.01
0.60
0.00
0.60
0.29
1.08
0.77
1.98
1.81
1.20
2.28
1.85
2.09
1.46
0.63
0.43
0.78
0.32
1.22
0.65
E
43
F
126
370
370
160
180
420
370
690
77
G
3260
3830
750
G
H
H
860
I
1740
1760
4310
1059
1905
1327
I
J
S
Mean
Std dev
176
83
267
215
Volume 50 June 2000
Journal of the Air & Waste Management Association 933

Chase et al.
Table 4. Gaseous and PM emissions results for high-mileage vehicles.
Vehicle ID
Weighted Gaseous Emissions (mg/mile)
CO
PM Emissions (mg/mile)
HC
NO
Phase 1
Phase 2
Phase 3
Weighted
x
Cars
K
160
240
170
172
180
940
440
560
300
530
198
1.90
2.28
1.77
2.25
1.10
0.69
0.25
0.32
-0.01
0.10
0.58
0.76
0.59
0.36
0.30
0.91
0.81
0.70
0.55
0.36
L
2460
1840
1785
1365
M
T
V
Mean
184
29
1678
508
406
138
1.86
0.43
0.27
0.24
0.52
0.17
0.67
0.19
Std dev
Trucks
N
210
210
220
500
174
1510
1580
3030
4000
3448
200
200
420
520
688
1.44
2.41
3.69
4.62
1.58
0.69
0.74
0.88
0.74
0.00
1.37
2.16
2.18
1.36
1.11
1.03
1.47
1.82
1.72
0.61
N
O
P
U
Mean
276
130
3006
911
457
177
2.95
1.25
0.58
0.34
1.60
0.41
1.35
0.48
Std dev
Th e results in Table 3 for th e low-m ileage trucks tell a
sim ilar story for th ose trucks usin g th e Californ ia RFG (I,
J, an d S). PM em ission s ran ged from 0.32 to 0.78 m g/m ile
for th e four tests, with a m ean value of 0.54 m g/m ile an d
a stan dard deviation of 0.21 m g/m ile, quite com parable
to th e cars. In fact, a pooled t-test sh owed th at th ere was
n o statistically sign ifican t differen ce between th e two sets
at th e 95% con fiden ce level. Put an oth er way, th e pooled
t-test put a probability of 30% in each of th e tails, a m uch
h igh er probability th at both sets are from th e sam e distri-
bution th an th e 2.5% or less in each tail required by th e
95% con fiden ce level.
h ad a sm aller average en gin e displacem en t (3.6 L vs. 4.3
L). In discussion s am on g th e auth ors, it was h ypoth esized
that a higher sulfur level in the EPA certification fuel m ight
be causin g th e differen ce, an d a study was in itiated to
determ in e th e effects of addin g sulfur to th e RFG on PM
em ission s.
Table 4 sum m arizes th e gaseous an d PM m easure-
m en ts for h igh -m ileage cars an d trucks. For both cars an d
trucks, th e average gaseous em ission s were all h igh er at
h igh er m ileage. For th e five cars, PM em ission s ran ged
from 0.36 to 0.91 m g/m ile, with a m ean of 0.67 m g/m ile
an d a stan dard deviation of 0.19 m g/m ile. A pooled t-test
to com pare th e PM em ission s m ean s of low an d h igh
m ileage cars sh owed n o statistically sign ifican t differen ce
between th e two groups (th ere was a 31% probability in
each of th e tails, m uch larger th an th e 2.5% cutoff). In
con trast, a com parison of th e h igh -m ileage cars with th e
h igh -m ileage trucks sh owed a statistically sign ifican t in -
crease of truck PM em ission s over th ose from cars (each
tail con tain ed on ly 1.3% probability, less th an th e 2.5%
cutoff). Th ere was also a statistically sign ifican t in crease
in PM em ission s from low to h igh m ileage for trucks fu-
eled with th e RFG (each tail con tain ed on ly 1.1% prob-
ability, less th an th e 2.5% cutoff).
However, low-m ileage trucks tested usin g EPA certifi-
cation fuel did n ot com pare closely with th ose tested us-
in g th e RFG. Note th at th e use of two differen t fuels was
n ot part of th e origin al testin g protocol, but som e trucks
were available for testin g early in th e study on ly with EPA
certification fuel. A pooled t-test applied between th e four
truck tests with RFG an d th e seven truck tests with EPA
certification fuel sh owed th at th ere was a statistically sig-
n ifican t differen ce between th e distribution s. More spe-
cifically, th e pooled t-test gave a probability of on ly 0.01%
in each tail, m uch sm aller th an th e 2.5% cutoff. Th us,
th ere would appear to be a fuel effect.
It is in terestin g to n ote th at th e th ree trucks with th e
lower PM em ission s (I, J, an d S) were older (1994–1996)
th an th e oth er four (1996–1998) an d h ad gen erally h igh er
m ileage (10901, 36201, an d 5461 m iles com pared with
m ileage all un der 8000 m iles). On th e oth er h an d, th ey
CONCLUSIONS
Generally, PM em issions were greatest in phase 1 of the
FTP, as were gaseous em issions. Exceptions observed m ay
be explained by m easurem ent variability. The variability
934 Journal of the Air & Waste Management Association
Volume 50 June 2000

Chase et al.
7. Maricq, M.M.; Podsiadlik, D.H.; Ch ase, RE. An Exam in ation of th e
Size-Resolved an d Tran sien t Nature of Motor Veh icle Particle Em is-
sion s; Environ. Sci. and Technol. 1999, 33, 1618-1626.
8. Maricq, M.M.; Ch ase, R.E.; Podsiadlik, D.H.; Siegl, W.O.; Kaiser, E.W.
The Effect of Dimethoxy Methane Additive on Diesel Vehicle Particulate
Emissions; SAE-982572; Society of Autom otive En gin eers: Warren dale,
PA, 1998.
9. Maricq, M.M.; Ch ase, R.E.; Podsiadlik, D.H.; Vogt, R. Vehicle Exhaust
Particle Size Distribution: A Comparison of Tailpipe and Dilution Tunnel
Measurements; SAE-1999-01-1461; Society of Autom otive En gin eers:
Warren dale, PA, 1999.
for gasoline vehicle particle mass emissions was greater than
gaseous em issions m easurem ents. At low and high m ile-
age for both cars and trucks using the sam e fuel (RFG), the
FTP com posite em ission rates of PM were below 2 m g/m ile.
Ph ase 1, th e cold start for trucks, approach es 3 m g/m ile.
At low m ileage (an d with RFG), car an d truck PM
em ission s did n ot differ sign ifican tly. PM em ission s from
cars were sim ilar at both low an d h igh m ileage, an d PM
em ission s from trucks were greater at h igh m ileage th an
at low m ileage.
10. Teflo filters are PTFE m em bran e disc filters, product n um ber R2PJ047,
m an ufactured by Pall Gelm an Scien ces, Laboratory Products Group,
An n Arbor, MI.
11. Measured usin g ASTM D 2986-71 0.3 m m (DOP) at 32 Lpm /100 cm 2
filter m edia by Pall Gelm an Scien ces.
12. Protection of th e En viron m en t; Code of Federal Regulations, Title 40;
U.S. Govern m en t Prin tin g Office: Wash in gton , DC, 1996; 40 CFR
86.096-8(a).
The variability of PM em issions as m easured for these
cars and trucks for low and high m ileage and for each of
the three FTP sam ples is low. This low variability supports
the assum ption of facility PM m easurem ent equivalence.
Large variability was observed in initial testing (not reported
here). The source of the variability was the use of a silicone
rubber hose between the vehicle and tunnel at one of the
test facilities, which was replaced with stainless steel.
Th ere m ay be a fuel effect. A greater PM em ission rate
was observed for trucks usin g EPA certification fuel th an
th ose usin g RFG. Because th is study was n ot design ed to
determ in e th e effects of differen t fuels, m ore work is war-
ran ted to ascertain th e m agn itude of a fuel effect, if on e is
sh own to exist.
ACKNOW LEDGMENTS
The authors appreciate input from and discussions with
Steven Japar and Matti Maricq. The authors also appreciate
the enthusiastic support of Adolfo Mauti, Michael J. Loos,
James E. Weir, and Ema Chladek at the VERL at Ford and of
Eric Hunsanger, Ken Kennedy, and Chris Laroo at the Gen-
eral Motors R&D Center Vehicle Emissions Laboratory.
About the Authors
Richard E. Chase is a senior technical specialist at the Sci-
entific Research Laboratory for Ford Motor Co., MD-3179
SRL, Dearborn, MI 48124. Gary J. Duszkiewicz is a product
test engineer at the Scientific Research Laboratory for Ford,
Trescott E. Jensen (corresponding author) is a staff techni-
cal specialist for Ford, and Desmonia Lewis is a research
technician specialist for Ford, MD-3179 SRL, Dearborn, MI
48124. E. John Schlaps is an instrumentation supervisor
for the DaimlerChrysler Corp., Plymouth Road Office, CIMS
514-13-42, 14250 Plymouth Road, Detroit, MI 48227-3086.
Arnold T. Weibel is an instrumentation specialist for
DaimlerChrysler at the Auburn Hills Headquarters Technol-
ogy Center, CIMS 486-01-81, 800 Chrysler Dr. E., Auburn
Hills, MI 48326-2757. Steven H. Cadle is a principal research
scientist for the Chemical and Environmental Sciences Labo-
ratory at General Motors Corp., General Motors R&D Cen-
ter, Bldg. 1-6, Mail Code 480-106-269, 30500 Mound Road,
Warren, MI 48090-9055, and Patricia Mulawa is a staff sci-
entist in the same lab at General Motors.
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