
October
5,
2005
1
Public
Consultation
Meeting
The
International
Consortium
for
Fire
Safety,
Health
&
the
Environment
and
U.
S.
EPA
Bill
Latus
Manager
 
Applied
Research
Briggs
&
Stratton
Corporation
October
5,
2005
2
Issues
for
Public
Review
and
Discussion

EPA
(
May
2005):
no
significant
increase
in
exothermic
measurements
claimed
in
EPA
testing
of
catalyzed
engines

Briggs
&
Stratton
cannot
replicate
the
EPA
results

Goal
today:
try
to
resolve
the
differences
October
5,
2005
3
EPA's
Catalyst
Evaluation
Class
1
 
Walk
behind
lawnmowers
October
5,
2005
4
HC+
NOx
and
CO
Conversion
with
Increasing
Secondary
Air
Using
Replicated
EPA
40cc
Catalyst
1.2
1.3
1.1
0.6
4.8
3.5
2.0
0.3
180
100
30
0
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
Increasing
Secondary
Air
Weighted
Specific
HC+

NOx
(

g/

kW­

hr)

0
20
40
60
80
100
120
140
160
180
200
Weighted
Specific
CO
(

g/

kWhr)
NOx
HC
CO
6.0
4.8
3.1
0.9
No
Air
October
5,
2005
5
Heat
from
Catalytic
Reactions
with
Increasing
CO
Conversion
Using
Replicated
EPA
40cc
Catalyst
2622
1412
471
0
500
1000
1500
2000
2500
3000
180
100
30
0
Weighted
Specific
CO
Conversion
(
g/
KW­
hr)

Total
Weighted
Heat
Released
(

BTU/

hr)
CO
HC+
NOx
31
627
1675
2956
Based
on
heat
of
catalytic
reactions
CO
­
10.7
BTU/
g
HC
­
49
BTU/
g
NOx
­
13.1
BTU/
g
October
5,
2005
6
Catalysts
 
Higher
Temperatures
WOT
Temperatures
with
Increased
CO
Conversion
Using
Replicated
EPA
40cc
Catalyst
1103
1000
796
751
651
887
822
831
735
766
716
676
600
650
700
750
800
850
900
950
1000
1050
1100
1150
180
100
30
0
Weighted
Specific
CO
Conversion
(
g/
kW­
hr)

Temperature
(

deg
F)
315
345
375
405
435
465
495
525
555
585
615
Temperature
(

deg
C)

Exhaust
Gas
Skin
(
Thermocouple)

Skin
(
Avg
Thermal
Image)
October
5,
2005
7
EPA
/
B&
S
Thermal
Images
EPA
Catalyst
(
dbl
KAT)
B&
S
Replicated
EPA
Catalyst
WOT
­
Secondary
Air
WOT
 
Secondary
Air
~
100
g/
kWh
CO
reduction
­
100
g/
kWh
CO
reduction
25.0
°
C
500.1
°
C
100
200
300
400
500
AR01
Ave
=
336F
Max
=
932F
Ave
=
340F
Max
=
824F
October
5,
2005
8
B&
S
Thermal
Images
Emissivity
 
Instrumentation
Calibration
B&
S
Replicated
EPA
Catalyst
B&
S
Replicated
EPA
Catalyst
WOT
 
Secondary
Air
WOT
 
Secondary
Air
­
100
g/
kWh
CO
reduction
­
100
g/
kWh
CO
reduction
­
unpainted
w/
o
emissivity
calibration
­
Painted
black
&
calibrated
SP01
SP02
AR01
AR01
Ave
=
352F
Max
=
838F
Ave
=
716F
Max
=
853F
October
5,
2005
9
30
g/
kWh
CO
Conversion
@
½
Load
180
g/
kWh
CO
Conversion
@
½
Load
Increased
CO
Conversion
effects
on
Temperature
Using
Replicated
EPA
40cc
Catalyst
SP01
SP02
AR01
SP01
SP02
AR01
Ave
=
565F
Max
=
718F
Ave
=
698F
Max
=
846F
October
5,
2005
10
Catalysts
 
Refueling
Temperatures
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
1500
0
60
120
180
240
300
Time
(
seconds)

Temperature
(

°

F)
­
20
80
180
280
380
480
580
680
780
Temperature
(

°

C)

Muffler
Skin
(
Catalyst)

Muffler
Skin
(
Std)

3
minutes
longer
to
cool
Note:
Engine
stabilized
75%
load
on
governor.

Ignition
killed
@
0
seconds.
October
5,
2005
11
Heat
Soak
after
Coast
Down
from
75%
Load
Using
B&
S
Low
Cost
Muffler
and
Replicated
EPA
40cc
Catalyst
B&
S
Muffler­
Engine
Off
20
sec
EPA
Catalyst­
Engine
Off
20
sec
SP01
AR01
SP01
SP02
AR01
Ave
=
568F
Max
=
743F
Ave
=
635F
Max
=
757F
October
5,
2005
12
Heat
Soak
after
Coast
Down
from
75%
Load
Using
B&
S
Low
Cost
Muffler
and
Replicated
EPA
40cc
Catalyst
B&
S
Muffler­
Engine
Off
2
min
EPA
Catalyst­
Engine
Off
2
min
SP01
AR01
SP01
SP02
AR01
Ave
=
397F
Max
=
484F
Ave
=
489F
Max
=
649F
October
5,
2005
13
100
g/
kWh
CO
Conversion
@
½
Load
180
g/
kWh
CO
Conversion
@
½
Load
CO
Conversion
effects
on
Temperature
Using
Replicated
EPA
40cc
Catalyst
SP01
SP02
AR01
SP01
SP02
AR01
Ave
=
644F
Max
=
797F
Ave
=
698F
Max
=
846F
October
5,
2005
14
Conditions
of
Concern
One
example:
misfire
October
5,
2005
15
Misfires
@
½
Load
Using
Replicated
EPA
40cc
Catalyst
½
Load
­
No
Misfire
~
50
g/
kWh
CO
Conversion
½
Load
with
Misfire
SP01
SP02
AR01
SP01
SP02
AR01
Ave
=
565F
Max
=
678F
Ave
=
664F
Max
=
864F
October
5,
2005
16
½
Load
with
Misfire
Replicated
EPA
40cc
Catalyst
½
Load
with
Misfire
B&
S
Muffler
SP01
SP02
AR01
SP01
AR01
Misfires
@
½
Load
Using
Replicated
EPA
40cc
Catalyst
Ave
=
489F
Max
=
626F
Ave
=
664F
Max
=
864F
October
5,
2005
17
Class
2
 
Riders
October
5,
2005
18
Catalysts
 
Increased
Surface
Temperatures
Ground
Cover
Ignition
Mod
28
OHV
Temperatures
@
Nominal
Operating
Conditions
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
100%
Load
75%
Load
50%
Load
25%
Load
10%
Load
Idle
Temperature
(

F)
7.0
in3
Catalyst
Nearly
Instantaneous
Ignition
Ignition
within
1
Minute
Likely
Ignition
Reference:

Danger
Of
Ignition
Of
Ground
Cover
Fuels
U.
S.
Dept
of
Agriculture
/
Forest
Service
Equipment
Development
&
Test
Report
5100­

15
November
1970
Muffler
w/
Catalyst
Misfire
w/
Catalyst
@
1/
2
Load
October
5,
2005
19
Catalysts
 
Misfires
@
½
Load
with
7.0
in
3
Catalyst
½
Load
without
Misfire
½
Load
with
Misfire
SP01
AR01
AR01
SP01
Ave
=
675F
Max
=
717F
Ave
=
894F
Max
=
984F
October
5,
2005
20
Catalyst
Failure

V­
Twin
catalyst
break­
in
test

Full
meltdown
due
to
sparkplug
failure

Temperatures
exceeded
1300C
(
2370F)


Normal
catalyst
operating
temperature
730C
(
1350F)


Maximum
catalyst
operating
temperature
1150C
(
1920)


Temperature
Increase
570C
(
1020F)
October
5,
2005
21
Interim
Conclusion

Significant
increases
in
exothermic
reactions
will
result
from
the
use
of
catalysts

Longer
"
cool
down"
periods
on
after
shutdown
increase
concerns
during
refueling
conditions
on
Class
1'
s

Higher
temperatures,
even
without
secondary
air,
increase
concerns
with
ground
cover
accumulation
on
Class
2'
s
