1

Regulatory

Announcement

 Printed on Recycled Paper

United States

Environmental Protection

Agency

Air and Radiation EPA420-F-98-018

May 1998

Office of Mobile Sources

A National Emission Control Program

The results of an EPA study completed in 1990 demonstrated the need for

control of air pollution in the nonroad engine and vehicle arena. EPA

published this finding in conjunction with the first rulemaking to set

emission standards for nonroad engines, which was completed in June

1994. In September 1997, the Agency issued a proposal for more stringent emission standards for diesel engines used in most nonroad applications. EPA has subsequently finalized emission standards for sparkignition nonroad engines rated at or below 19 kilowatts, which consist

predominantly of residential and commercial lawn care equipment. The

Agency is now considering proposing a national program to control

emissions of oxides of nitrogen (NOx) and hydrocarbons from large

spark-ignition nonroad engines. These engines are used in a variety of

industrial equipment, including forklifts, airport ground-service equipment, generators, and compressors. EPA is publishing an Advance Notice

Advance Notice of Proposed Rulemaking:

Emission Standards for New Large

Spark-Ignition Nonroad Engines

The U.S. Environmental Protection Agency (EPA) is issuing an

advance notice of proposal for control of emissions from new sparkignition engines rated above 19 kilowatts (25 horsepower). Control of

emissions from this currently unregulated source moves the Agency

one step further in the initiative to reduce the harmful health effects of

ozone and particulate matter from nonroad engine sources.
2

of Proposed Rulemaking (ANPRM) to encourage a broader dialogue

with the public regarding the emission standards under consideration.

Many of the engines that would be affected by these new emission

standards have counterpart engine models used in highway applications.

While highway engines have seen extensive technological developments,

the nonroad engine designs have changed little to reflect these improvements. Shifting toward these technologies that have been developed for

cars and trucks, such as electronically controlled closed-loop injection

systems with three-way catalysts, there is a great potential to dramatically improve engine performance and fuel economy in addition to the

anticipated emission reductions.

Emissions from Large Spark-Ignition Nonroad

Engines

If the standards are implemented as discussed, the resulting emission

reductions would translate into significant, long-term improvements in

air quality in many areas of the U.S. Application of basic automotive

emission control technologies would reduce NOx and hydrocarbon

emissions by 70 to 90 percent. The emission standards being considered

are part of an overall program designed to ensure that engine emissions

are controlled throughout a lifetime of field operation, not just in the

laboratory. Overall, the program would provide much-needed assistance

to states facing ozone and particulate air quality problems that are

causing a range of adverse health effects for their citizens, especially in

terms of respiratory impairment and related illnesses.

Public Participation Opportunities

EPA desires full public participation in the rulemaking process. The

Agency solicits comments from all interested parties. Wherever applicable, full supporting data and detailed analysis should also be submitted

to allow EPA to make maximum use of the comments. Commenters are

especially encouraged to provide specific suggestions for changes to any

aspects of the proposal that they believe need to be modified or improved.

EPA will accept comments on the ANPRM for 30 days after publication

in the Federal Register. For instructions on submitting written comments, please see the Federal Register notice, which is available from
3

the EPA Air and Radiation Docket by calling 202-260-7548; please refer

to Docket No. A-98-1. In addition, the ANPRM and related documents

are available electronically via the EPA Internet server at:

http://www.epa.gov/OMSWWW/equip-hd.htm

There will also be an opportunity for oral and written comment when

EPA publishes a subsequent Notice of Proposed Rulemaking.

For More Information

Document information is also available electronically at the Internet site

given above, or by writing to:

U.S. Environmental Protection Agency

Office of Mobile Sources

2000 Traverwood

Ann Arbor, MI 48105