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Frequently Asked

Questions

 Printed on Recycled Paper

United States

Environmental Protection

Agency

Air and Radiation EPA420-F-03-009

April 2003

Office of Transportation and Air Quality

EPA's Proposed Program for

Low-Emission Nonroad

Diesel Engines and Fuel

The U.S. Environmental Protection Agency (EPA) is proposing a new

program that would greatly reduce exhaust emissions of particulate

matter and nitrogen oxides from nonroad diesel engines. This fact

sheet addresses frequently asked questions about this proposed

program.

Why is EPA concerned about emissions from

nonroad diesel engines?

Nonroad diesel engines contribute greatly to continuing air quality

problems in the United States. The engines affected by the proposal

currently account for about 44 percent of total diesel particulate matter

(PM) emissions and about 12 percent of total nitrogen oxides (NOx)

emissions from mobile sources nationwide; these proportions are even

higher in some urban areas. In addition, nonroad diesel engines will

produce a growing share of overall emissions over the next several years

as other emission-control programs take effect for cars and trucks and

other sources of nonroad emissions. Emissions from these engines

contribute to serious public health problems. To address this, Congress

directed EPA in the 1990 Clean Air Act to set emission standards for

nonroad engines that contribute to air pollution.
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What does the proposal cover?

The proposal includes emission standards for diesel engines used in most

nonroad equipment. The proposal also specifies improvements to the

quality of the fuel these engines use. Nonroad diesel engines are used in

many applications, including construction, agricultural, industrial, and

airport equipment. To illustrate the wide range of applications, this

proposal would apply to: a 3-horsepower pump, a 30-horsepower

trenching machine, a 300-horsepower bulldozer, and a 3,000-horsepower

mining truck. The new standards would take effect starting in 2008 and

be fully phased in by 2014.

Manufacturers will likely meet the proposed emission standards by using

advanced emission-control technologies, much like car manufacturers

developed the catalytic converter to control automotive emissions in

response to EPA standards. These technologies will significantly reduce

emissions, but they require fuel that has a much lower sulfur content than

today’s diesel fuel. The proposal therefore includes a limit on the amount

of sulfur in fuel. This low-sulfur fuel would then be available for use by

the nonroad engines by the time the new technologies reach the marketplace. This cleaner fuel can be used without harm in existing engines and,

in fact, will also reduce emissions of particulate matter from these older

engines.

The proposal does not cover diesel engines used in highway trucks,

locomotives, marine vessels, or stationary equipment, all of which are

subject to separate requirements. However, we are proposing to substantially reduce the sulfur level of diesel fuel used in locomotive and marine

applications to reduce emissions of particulate matter from these engines

and are seriously considering further improvements in fuel quality for

these engines to make possible the same kind of advanced technologies

that manufacturers would be developing for this proposal.

What is EPA trying to accomplish with the proposal?

This proposal would reduce NOx and PM emissions from nonroad diesel

engines by more than 90 percent and, as a result, provide a wide range of

public health benefits. We have estimated that, by 2030, controlling these

emissions would annually prevent 9,600 premature deaths, over 8,300

hospitalizations, and almost a million work days lost. The monetized

health benefits of this proposal would be $81 billion annually once the

program is fully phased in. Costs for both the engine and fuel requirements would be significantly less, at approximately $1.4 billion annually.
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Why does it take so long before the standards take

effect?

Manufacturers of nonroad diesel engines are working to meet EPA

emission standards adopted over the last eight years. Some of these

older standards start as late as 2006, so it will take an additional period

of stable emission standards for manufacturers to design and produce

their engines so they meet the proposed standards. Manufacturers are

also preparing to apply the advanced emission-control technologies to

engines used in highway trucks and buses, starting in 2007; these technologies will then be adapted for nonroad applications. In addition,

some nonroad engines are very different than highway engines, especially

those below 50-horsepower, so manufacturers will need additional

innovation to produce these engines with low emissions.

Oil refiners are already investing in efforts to meet requirements to

produce low-sulfur fuels for diesel engines used in highway vehicles

starting in 2006. These companies will use the available lead time to

apply the same approaches to produce low-sulfur fuels for nonroad

engines. The process to remove sulfur from the fuel is well understood,

but it takes considerable capital investments and time to make the necessary refinery modifications.

How much will the proposed program cost?

The estimated costs vary widely for equipment of different sizes and for

different applications. For the vast majority of equipment, the cost of

meeting emission standards will be roughly one to two percent compared

with the typical retail price. Costs could range higher for some types of

equipment. As an example, for a 175-horsepower bulldozer, it will cost

an estimated $2,600 more to add the advanced emission-control systems

to the engine and to design the bulldozer to accommodate the modified

engine. A new 175-horsepower bulldozer costs approximately

$230,000, so the increased costs are about one percent of the total

purchase price. In addition, engines running on low-sulfur fuel will have

reduced maintenance expenses that we estimate will be equivalent to

reducing the cost of the fuel by 3.3 cents per gallon.
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What about controlling emissions from locomotive

and marine diesel engines?

This proposal includes no new emission standards for locomotive or

marine diesel engines. We are currently implementing emission standards

for locomotives that will be fully phased in by 2005 and for marine diesel

engines that will be fully phased in by 2009. In this proposal, we are

including a requirement that locomotive and marine diesel engines also

use low-sulfur fuel. This will reduce emissions of particulate matter from

existing and future models. In addition, we are seriously considering

whether to establish new emissions standards and requirements for even

lower fuel sulfur levels in the future that would reduce the emissions from

locomotive and marine engines by more than 90 percent with the same

advanced emission-control technologies considered in developing this

proposal.

Which industries will be affected by this proposal?

Engine manufacturers and fuel refiners will have the biggest responsibility

to meet the proposed requirements. Many of these companies have been

working for several years and investing substantially to improve their

products and processes to make this proposal possible. We will continue

to work closely with these companies during the time before the standards take effect to ensure a smooth transition to the new standards.

Additional industries that will be affected include fuel distributors and

equipment manufacturers.

Why doesn’t EPA just ban diesel engines?

There is no reason to ban diesel engines. In fact, today’s advanced

technologies and clean fuels are making it possible for manufacturers to

offer diesel engines that perform well with very low emissions. Also,

diesel engines have many advantages as a power source for nonroad

equipment, including wide availability, fuel efficiency, and low cost.

Diesel engines have been powering equipment for the last 100 years.

There are currently about 10 million nonroad diesel engines operating in

the United States, performing an unimaginable variety of essential jobs.

New advances in emission-control technology will allow the continued

use of nonroad diesel engines to meet these needs—without compromising the nation’s air quality.
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Are other countries doing this too?

The United States is the first nation to propose a coordinated systems

approach—involving both engine and fuel changes—to achieve these

significant reductions in NOx and PM emissions from nonroad diesel

engines. The European Union has proposed emission standards that

would require advanced technologies for reducing PM emissions. Both

the European Union and Japan have contributed significantly to this

proposal and are considering similar programs for their countries. Engine

manufacturers usually try to sell the same engines in many different

countries, so harmonizing international standards is an important goal.

Where Can I Get More Information?

For more information on the environmental and health impacts of these

proposed emission standards, see the fact sheet: “Public Health and

Environmental Benefits of EPA’s Proposed Program for Low-Emission

Nonroad Diesel Engines and Fuel” (EPA420-F-03-010) and the Draft

Regulatory Impact Analysis for this proposed rule. You can access these

documents and others related to the rulemaking on our Web site at:

www.epa.gov/nonroad

You can also contact us at:

U.S. Environmental Protection Agency

Assessment and Standards Division

2000 Traverwood Drive

Ann Arbor, MI 48105

Voice-mail: (734) 214-4636

E-mail: asdinfo@epa.gov