United States             Air and Radiation         EPA420-F-00-046
                   Environmental Protection                         November 2000

                   Office of Transportation and Air Quality
vxEPA      Regulatory
                   Emission Standards for New Nonroad
                   Engines and Highway Motorcycles
                   The U.S. Environmental Protection Agency (EPA) is publishing an
                   Advance Notice of Proposed Rulemaking concerning emissions from
                   new nonroad vehicles and engines that are currently unregulated, and
                   highway motorcycles. Control of emissions from these engines will help
                   reduce the harmful health effects of ozone, carbon monoxide, and
                   particulate matter from     nonroad and highway engines.
                  Since 1994, EPA has established emissions control programs under the
                  Clean Air Act for various classes and categories of nonroad engines,
                  including those used in farm and construction, marine, locomotive, and
                  lawn and garden applications. With the Advance Notice being released
                  today, the Agency is seeking early input on our plan to propose a na-
                  tional program to control emissions from engines used in nonroad
                  applications that remain unregulated. These include:

                     industrial spark-ignition engines rated above 19 kW (25 hp) (e.g.,
                      forklifts and generators);
                     recreational gasoline engines (e.g., snowmobiles and off-road
                    * and recreational marine diesel engines and all sterndrive and in-
                      board gasoline engines.
                                                          > Printed on Recycled Paper

In addition, we are requesting comment on possible emission reductions
from highway motorcycles as part of this rulemaking. We are raising
these questions because there may be opportunities to reduce emissions
from these vehicles. There are also potential issues of consistency in
standards between nonroad and highway motorcycles. Current EPA
emission standards for highway motorcycles were established more than
20 years ago.

We are also announcing a final finding that nonroad spark-ignition (SI)
engines (engines powered by gasoline, natural gas or liquified petroleum
gas) rated above  19 kW and land-based recreational engines contribute to
air pollution in more than one nonattainment area in the U.S. With this
Final Finding, we are obligated under the Clean Air Act to set emission
standards requiring the greatest degree of emission reduction achievable,
considering several factors.
Emissions from these engines together account for about 11 percent of
hydrocarbon (HC) emissions, 9 percent of carbon monoxide (CO) emis-
sions, and 3 percent of oxides of nitrogen (NOx) emissions from mobile
sources. The anticipated emission standards would significantly reduce
emissions from engines that contribute to ozone formation and poten-
tially expose people to high concentrations of poisonous CO exhaust and
air toxics. Emission reductions will provide much-needed assistance to
states facing ozone,  CO, and particulate matter air quality problems that
are causing a range of health problems for their citizens, especially
respiratory impairment and related illnesses. In addition, personal expo-
sure to high levels of CO, particulate matter (PM), and air toxics raises
health concerns for many  individuals.

Recreational vehicles include snowmobiles, off-road motorcycles (dirt
bikes), and all-terrain vehicles (ATVs). The program could also affect
some motorized scooters, mini-bikes, and mopeds. The Advance Notice
focuses on potential reductions in HC and CO. Many recreational ve-
hicles are equipped with 2-stroke engines and have very high emissions
of HC and CO. Recreational vehicles currently contribute about 8 percent
of HC emissions and 5 percent of CO emissions from mobile sources. In
addition, we expect some reduction in PM and air toxics emissions.

We are also interested in opportunities to reduce emissions from high-
way motorcycles along with off-road motorcycles. California's emission
standards for highway motorcycles, which are more stringent than
federal standards, are being considered internationally. There may be
opportunities to harmonize with such programs to effectively reduce
emissions nationwide.

In the Advance Notice, we request comment on several issues and areas
of information, including:

    technologies that may be available to reduce emissions and the cost
    of those technologies
    the timing and level of new emission standards
    test procedures for measuring emissions from vehicles and engines
    compliance programs, including production-line and in-use testing
    by manufacturers
We plan to propose a national program to control emissions from un-
regulated marine propulsion engines. Emission standards for recreational
marine diesel engines will focus on NOx and PM. For sterndrive and
inboard gasoline engines, we anticipate a significant reduction in NOx,
CO, and HC emissions.

This Advance Notice anticipates a proposal containing three important
sets of provisions. First, emission standards will establish the level of
stringency that manufacturers must achieve when designing their en-
gines. Emission-control technologies we will be evaluating for recre-
ational marine diesel engines include established engine technologies
such as seawater aftercooling, and high-pressure fuel injection, perhaps
with electronic controls.  For sterndrive and inboard engines we are
considering emission standards based on the use of three-way catalytic
converters, electronic fuel injection, and exhaust gas recirculation, all of
which have become commonplace in automotive engines.

Second, we are seeking comment on testing provisions that would
require engine manufacturers to show they can meet emission standards
over a variety of operating conditions. These testing  requirements may
be very similar to those already adopted for commercial marine diesel

Finally, we discuss certification and compliance provisions to help us
ensure that each engine is able to control emissions over its full lifetime.
Much of this will follow from other programs for similar engines, but it
will also reflect the unique characteristics of these engines.

We intend to propose a national program to control emissions of CO,
NOx, and HC from large nonroad spark-ignition engines, which may
operate on gasoline, natural gas or liquified petroleum gas. These engines
are used in a variety of industrial equipment, including forklifts, airport
ground-service equipment, generators, and compressors.

Even though these engines are very similar to, or are built from, base
automotive engines, nonroad engine designs  have changed little over the
years. Adopting basic automotive emission-control technologies allows
for dramatic improvements to engine performance and fuel economy in
addition to the expected emission reductions.

Under the anticipated control program, manufacturers would use elec-
tronic fuel injection and catalytic converters to meet emission standards.
The California Air Resources Board (California ARB) adopted emission
standards for Large SI engines in October 1998. Further engine testing
and a concern for off-cycle emissions has led us to consider several
provisions not adopted by California ARB, most notably:

    A more stringent emission standard to more accurately reflect the
     in-use deterioration of emission controls
    A duty cycle that includes transient engine operation
  *  Not-to-exceed testing and emission standards
    Basic engine diagnostic requirements
    Measures to reduce evaporative emissions from gasoline-fueled
We are releasing the Advance Notice to encourage full public participa-
tion in the rulemaking development process. We especially encourage
commenters to provide specific suggestions and data in the areas we

For instructions on submitting written comments, please see the Federal
Register notice, which is available from the EPA Air and Radiation
Docket by calling 202-260-7548 (refer to Docket A-2000-01). We are
also accepting comments via e-mail at "nranprm@epa.gov". In addition,
you can access the Advance Notice and related documents electronically
on the Office of Transportation and Air Quality (OTAQ) Web site at:

  www. epa.gov/otaq

There will also be an opportunity for oral and written comment when we
later publish a Notice of Proposed Rulemaking.
You can access documents on this rulemaking electronically on the
OTAQ Web site given above, or by contacting Margaret Borushko at:

U.S. Environmental Protection Agency
Office of Transportation and Air Quality
2000 Traverwood Drive
Ann Arbor, MI 48105