Results
of
Section
610
Review
of
Emission
Standards
for
Nonroad
Spark
Ignition
Engines
Rated
at
or
Below
19
Kilowatts
On
July
3,
1995
(
60
FR
34598),
EPA
promulgated
a
rule
setting
emission
standards
for
nonroad
spark­
ignition
(
SI)
engines
rated
at
or
below
19
kilowatts
under
authority
of
Section
213
of
the
Clean
Air
Act.
These
standards
are
codified
in
the
Code
of
Federal
Regulations
at
40
CFR
Part
90.
Pursuant
to
Section
610
of
the
Regulatory
Flexibility
Act,
EPA
has
reviewed
this
rule
to
determine
if
it
should
be
continued
without
change,
or
should
be
rescinded
or
amended
to
minimize
adverse
economic
impacts
on
small
entities.
EPA
considered,
and
solicited
comments
on,
the
following
factors:
(
1)
The
continued
need
for
the
rule;
(
2)
the
nature
of
complaints
or
comments
received
concerning
the
rule;
(
3)
the
complexity
of
the
rule;
(
4)
the
extent
to
which
the
rule
overlaps,
duplicates,
or
conflicts
with
other
Federal,
State,
or
local
government
rules;
and
(
5)
the
degree
to
which
technology,
economic
conditions,
or
other
factors
have
changed
in
the
area
affected
by
the
rule.
The
results
of
EPA's
review
are
summarized
here.

Background
The
purpose
of
the
requirements
of
emission
standards
and
related
provisions
for
nonroad
spark
ignition
(
SI)
engines
rated
at
or
below
19
kilowatts
(<
19kW)
is
to
improve
ambient
air
quality.
Pursuant
to
section
213
of
the
Clean
Air
Act
as
amended
in
1990
(
CAA
or
the
Act),
EPA
was
required
to
set
new
standards
for
these
engines
if
(
1)
a
determination
was
made
that
emissions
from
nonroad
engines
"...
cause,
or
significantly
contribute
to,
air
pollution
which
may
reasonably
be
anticipated
to
endanger
public
health
or
welfare"
And,
if
an
affirmative
determination
is
made
with
regard
to
(
1)
above,
then
EPA
was
to
(
2)
determine
if
carbon
monoxide,
oxides
of
nitrogen,
and
volatile
organic
compounds
from
new
or
existing
nonroad
engines
or
nonroad
vehicles
"...
are
significant
contributors
to
ozone
or
carbon
monoxide
concentrations
in
more
than
1
area
which
has
failed
to
attain
the
national
ambient
air
quality
standards
(
NAAQS)
for
ozone
or
carbon
monoxide."
If
affirmative
determinations
are
made
for
the
first
study
("
cause
or
significantly
contribute"
and
the
second
study
"
significant
contributor
to
ozone
or
carbon
monoxide
nonattainment
in
more
than
one
area"),
then
EPA
was
mandated
to
set
standards
applicable
to
emissions
from
those
classes
or
categories
of
new
nonroad
engines
and
new
nonroad
vehicles
"...
which
in
the
Administrator's
judgment
cause
or
contribute
to
such
air
pollution."

The
first
study
was
completed
in
November
1991
and
can
be
found
in
public
docket
A­
91­
24.
Subsequently,
EPA
determined
that
nonroad
SI
engines
<
19kW
(
small
SI)
do
contribute
to
ozone
and
CO
nonattainment
(
see
59
FR
31306
published
in
the
Federal
Register
on
June
17,
1994)
and
embarked
on
a
rulemaking
for
setting
hydrocarbon+
oxides
of
nitrogen
(
HC+
NOx)
and
carbon
monoxide
(
CO)
emission
standards
for
these
engines.
A
Notice
of
Proposed
Rulemaking
was
published
in
the
Federal
Register
on
May
16,
1994
(
59
FR
25399)
and
a
Final
Rule
was
published
on
July,
3,
1995
(
60
FR
34598).
These
requirements
are
codified
in
40
CFR
90.

Regulatory
Flexibility
Act
Section
610
Review
Pursuant
to
Section
610
of
the
Regulatory
Flexibility
Act,
the
Agency
has
reviewed
the
1995
rule
that
set
requirements
for
emission
standards
and
related
provisions
for
nonroad
SI
engines
rated
<
19kW.
This
review
was
announced
in
the
Regulatory
Agenda
on
June
28,
2004
(
69
FR
38183).
In
the
June
28
announcement,
the
Agency
solicited
comment
on
five
factors
that
are
addressed
below.
No
comments
were
received.

Discussion
of
Five
Factors
1.
Continued
need
for
the
rule
One
of
the
factors
that
must
be
considered
in
a
section
610
review
is
the
continued
need
for
the
rule
under
review.
The
Agency
finds
that
there
is
a
continued
need
for
the
emission
standards
and
related
provisions
for
nonroad
SI
engines
rated
at
<
19kW
rules.
Many
areas
of
the
country
do
not
meet
the
8­
hour
ozone
NAAQS
and
there
are
even
areas
which
still
do
not
meet
the
CO
NAAQS.
Both
of
these
environmental
problems
are
addressed
in
part
by
the
1995
rule.
In
addition,
the
Agency
has
taken
a
second
step
beyond
the
1995
rule
to
further
reduce
emissions
from
these
same
sources,
and
is
in
the
process
of
taking
a
third
step.
Subsequent
to
the
1995
rule,
EPA
published
Phase
2
standards
for
the
same
regulated
sources
(
see
65
FR
24305
published
April
25,
2000)
and
is
now
developing
a
separate
action
for
Phase
3
standards.

2.
Nature
of
complaints
or
comments
received
concerning
the
rule.

No
public
comments
were
received
during
the
review
period
for
the
1995
rule.

3.
Complexity
of
the
Rule
The
Agency
must
also
consider
the
complexity
of
the
rule
under
review.
The
rule
under
review
includes
performance­
based
exhaust
emission
standards,
certain
prohibitions,
administrative
requirements,
waiver
procedures,
and
other
flexibilities
related
to
program
implementation.
More
specifically,
the
performance
standards
are
broken
into
five
classes
two
for
nonhandheld
engines
and
three
for
handheld
engines.
These
are
further
defined
by
engine
displacement.
The
rule
also
included
prohibitions
against
selling
uncertified
engines,
importation
restrictions,
and
tampering.
Administrative
requirements
included
a
full
certification
program,
recordkeeping,
and
labeling.
At
this
point
engines
used
solely
for
competition,
produced
for
manufacturer
use,
display,
or
military
specific
applications
are
not
covered.
Finally,
the
rule
included
a
number
of
interim
flexibilities
related
to
useful
life,
in­
use
enforcement,
and
phase­
out
provisions
for
2­
stroke
lawnmowers.
Many
of
the
program
provisions
outlined
above
are
still
necessary
in
the
program.
However,
in
the
Phase
2
rule
mentioned
above,
EPA
included
useful
life
requirements
for
each
of
the
five
engine
classes
and
also
incorporated
a
broad
emission
credit
averaging,
banking,
and
trading
to
enhance
compliance.
EPA
believes
that
the
flexibilities
afforded
by
these
provisions
mitigates
the
rule's
complexity
to
the
extent
possible
while
meeting
statutory
objectives.

4.
Extent
to
which
the
rule
overlaps,
duplicates,
or
conflicts
with
other
Federal,
State,
or
local
government
rules
The
Agency
must
also
consider
the
extent
to
which
the
<
19kW
nonroad
SI
engine
rule
overlaps,
duplicates,
or
conflicts
with
other
Federal,
State,
or
local
government
rules.
The
Agency
believes
the
rules
for
<
19kW
nonroad
SI
engines
do
not
duplicate
or
conflict
with
any
other
rule.
Under
the
CAA,
both
EPA
and
the
state
of
California
are
authorized
to
have
emission
control
program
requirements
programs
covering
these
engines
and,
indeed,
both
do
now
have
programs.
While
these
program
requirements
are
similar,
and
50­
state
certification
of
engines
is
common,
no
other
state
has
adopted
the
California
program.
Furthermore,
under
CAA
provisions,
only
EPA
can
set
standards
for
engines
used
in
farm
and
construction­
related
small
SI
equipment.
Thus,
the
EPA
program
is
fully
necessary
to
achieve
our
national
air
quality
objectives,
and
does
not
duplicate
or
overlap
unnecessarily
with
other
programs.

5.
The
degree
to
which
technology,
economic
conditions,
or
other
factors
have
changed
in
the
area
affected
by
the
rule
Finally,
the
Agency
must
consider
the
length
of
time
since
the
rule
in
question
has
been
evaluated,
or
the
degree
to
which
technology,
economic
conditions,
or
other
factors
have
changed
in
the
area
affected
by
the
rule
under
review.
The
Agency
is
continually
evaluating
the
<
19
kW
rule
requirements.
As
mentioned
above,
we
have
revised
the
rule
significantly
once
since
the
original
implementation
and
in
addition
have
conducted
one
technology
review
which
resulted
in
a
rule
modification.
There
have
been
a
number
of
changes
to
and
improvements
in
small
SI
engines
since
the
mid­
1990s
when
the
rule
was
first
promulgated
and
there
has
been
a
continual
evolution
in
the
number
and
type
of
products
using
these
engines.
There
are
more
engine
and
equipment
product
offerings
today
than
ever
before
and
recently
the
economic
impacts
of
changes
in
the
retail
marketing
scheme,
off­
shore
engine
and
equipment
production,
and
engine
imports
are
becoming
significant.
The
overall
market
remains
strong
and
growing.

Conclusion
Equipment
using
small
SI
engines
continues
to
be
significant
contributors
to
ozone
and
CO­
related
air
pollution
emission
inventories.
The
programs
now
in
place
have
effectively
reduced
emission
inventories
from
their
original
levels
and
what
the
levels
would
have
been
with
future
growth
in
equipment
populations
and
activity.
To
ensure
that
these
reductions
are
maintained
and
that
future
engine
and
equipment
technology
meets
requirements,
it
is
important
to
maintain
the
national
standards
and
related
provisions
established
for
such
programs.
Furthermore,
there
is
a
statutory
requirement
for
these
standards
and
related
requirements.
Without
the
<
19
kW
rule,
air
pollutant
emissions
from
in­
use
equipment
using
small
SI
engines
would
be
substantially
greater,
posing
negative
effects
on
human
health
and
the
environment.

Based
on
EPA's
Section
610
review,
including
the
fact
that
no
comments
were
received
as
a
result
of
the
review,
no
amendments
based
upon
that
review
are
planned
at
this
time.
Nevertheless,
as
part
of
the
Phase
3
effort
described
above,
EPA
will
review
the
entire
rule
and
propose
minor
modifications
as
needed
to
improve
its
efficiency
and
effectiveness
going
forward.
As
we
pursue
these
efforts,
we
will
continue
to
be
mindful
of
potential
small­
entity
impacts,
and
will
work
to
minimize
them
consistent
with
statutory
mandates
and
environmental
objectives.
EPA
expects
that
the
current
and
future
rules
will
be
significant
in
helping
to
provide
emission
inventory
reductions
needed
in
states
with
areas
newly
designated
nonattainment
under
EPA's
8­
hour
ozone
standard.
