Toward a Cleaner Future


Office of Transportation and Air Quality


Progress Report 2005


Table of Contents 

Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3


What is OTAQ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6


The National Vehicle and Fuel Emissions Laboratory . . . . . . . 7


Clean Cars and Fuels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8


Clean Trucks, Buses, and Diesel Fuels . . . . . . . . . . . . . . . . . . 12


Clean Nonroad (Off-Highway) Engines and Fuels . . . . . . . . . . 14


Certification and Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . 17


The National Clean Diesel Campaign . . . . . . . . . . . . . . . . . . . 20


Transportation and Global Climate Change. . . . . . . . . . . . . . . 23


International Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27


Looking Forward . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29


Executive Summary


Controlling pollution from mobile sources is vital 

to improving the quality of our air and protecting 

public health. The Clean Air Act of 1990 empowered the U.S. Environmental Protection Agency (EPA) to 

take a variety of actions that has achieved significant 

results. For example, EPA reduced the sulfur in gasoline 

and diesel fuels and established successively more stringent emission standards, both of which brought about 

cleaner and better performing vehicles and engines. 

Several programs have resulted in substantial emission 

reductions and health benefits. In fact, the emission 

reductions resulting from the clean fuel and vehicle 

standards finalized over the past several years will prevent more than 24,000 premature deaths, 19,000 hospitalizations, and 3.2 million work days lost. When fully 

implemented in 2030, the annual net benefits of these 

programs will be approximately $175 billion, compared 

to $11 billion in costs. 

This report presents the most recent developments in 

the EPA Office of Transportation and Air Quality’s 

(OTAQ’s) key program areas, as EPA continues to 

progress under the Clean Air Act. These accomplishments would not have been possible without our stakeholders’ involvement and support. This report is a tribute 

to their concerted efforts on behalf of the environment. 

Clean Cars and Fuels. One of OTAQ’s top priorities 

is making sure that new cars, and the fuels they use, 

Office of Transportation and Air Quality — Progress Report 3 
are meeting what is known as the “Tier 2 vehicle standards.” Starting in 2004, with plans to be fully implemented in 2009, EPA’s Tier 2 Vehicle and Gasoline 

Sulfur Program represents a groundbreaking pollution 

control strategy for motor vehicles. This program will 

make new cars, sport utility vehicles (SUVs), pickup 

trucks, and vans 77 to 95 percent cleaner than 2003 

models, while reducing sulfur levels in gasoline by 90 

percent. Manufacturers are bringing to market the 

cleaner vehicles faster than required, with 35 percent 

of vehicles meeting the new standard in the first year. 

Clean Trucks, Buses, and Diesel Fuels. Heavyduty trucks and buses are significant sources of air pollution. EPA’s Clean Diesel Truck and Bus Program sets 

stringent emission standards for diesel engines and 

calls for the introduction of clean, ultra low-sulfur diesel 

fuel. Beginning in 2007, new highway diesel engines 

will be as much as 95 percent cleaner than current 

Dramatic Emission Reductions


OTAQ’s programs have resulted in dramatic emission 

reductions. Compared to 1995 baselines, these programs 

reduced pollutants by the following amounts in 2004: 

■ 1.85 million tons of volatile organic compounds 

■ 1.45 million tons of nitrogen oxides 

■ 25,000 tons of particulate matter 

■ 18,000 tons of fine particulate matter 

■ 11.3 million tons of carbon monoxide 

models, and sulfur levels in fuel will be reduced by 

more than 97 percent, to 15 parts per million (ppm). 

OTAQ is working closely with engine manufacturers, 

trucking companies, and refiners to ensure the smooth 

implementation of these new standards. 

Clean Nonroad Engines and Fuels. From large 

agricultural machines to residential leaf blowers, nonroad engines emit large quantities of harmful particulate matter and nitrogen oxides. OTAQ has developed a 

comprehensive set of fuel and engine requirements 

that will reduce sulfur in nonroad diesel by more than 

99 percent by 2010. More stringent standards for locomotive, large marine diesel, and small gasoline (e.g., 

lawn and garden) engines are currently being developed. In addition, EPA has established standards for 

recreational and other nonroad engines, such as those 

found on motorcycles, all-terrain vehicles, and snowmobiles, that will reduce nitrogen oxides, particulate 

matter, hydrocarbons, and carbon monoxide by 20 to 

99 percent, depending on the vehicle engine type. 

Certification and Compliance. EPA’s certification 

and compliance programs ensure that vehicles and 

engines are designed to meet emission standards 

when they first enter the market and that they continue to meet those standards throughout their useful 

life. OTAQ monitors the environmental performance of 

vehicles on the road and works with manufacturers to 

recall vehicles that fail to meet standards. In 2004, automotive manufacturers voluntarily recalled 2.7 million 

vehicles, representing 35 different emission-related 

problems. These recalls will prevent the release of thou4 Office of Transportation and Air Quality — Progress Report 
sands of tons of pollutants into the air. OTAQ also now 

certifies 2,300 engine models, up from about 300 in the 

early 1990s. 

The National Clean Diesel Campaign. In 2004, 

EPA crafted a comprehensive initiative to implement 

diesel regulations for future engines and address the 

emissions of the 11 million diesel engines in use today. 

With this campaign, EPA is targeting specific diesel 

applications. For example, under Clean School Bus 

USA, more than 15 million residents and 2 million children in 150 school districts now benefit from cleaner 

air due to cleaner buses. 

Transportation and Global Climate Change. 

In addition to emissions that contribute to urban air 

pollution, the transportation sector accounts for 

30 percent of U.S. greenhouse gas emissions. 

EPA is working on solutions. For example, 

OTAQ’s automotive engineers are developing 

advanced technologies, such as clean diesel 

combustion and hydraulic hybrids, and working 

with commercial partners to bring these 

hybrids to market. In addition, OTAQ’s voluntary 

initiatives are helping thousands of partners save 

billions of gallons of fuel—and thereby reduce carbon dioxide emissions—by implementing best shipping 

and delivery practices and by encouraging employers 

to offer outstanding commuter benefits. 

International Programs. Nearly every 

country in the world suffers from air pollution, and each year more and more 

of it is generated from the transportation sector. During the 2002 

World Summit for Sustainable 

Office of Transportation and Air Quality — Progress Report 5 

Development (WSSD) in Johannesburg, South Africa, 

EPA led the development of the Partnership for Clean 

Fuels and Vehicles (PCFV), which is made up of more 

than 70 members from around the world. As a leading 

and founding member of the PCFV, EPA participates in 

numerous international efforts to reduce air pollution 

from vehicles, such as helping countries remove lead 

from gasoline, reduce emissions from engines, and 

lower sulfur in fuels. 
What Is OTAQ? 

The Office of Transportation and Air Quality (OTAQ) is 

housed within EPA’s Office of Air and Radiation. OTAQ’s 

mission is to protect public health and the environment 

by reducing air pollution from motor vehicles, engines, 

and the fuels used to operate them and by encouraging 

business practices and travel choices that minimize 

emissions. OTAQ’s programs address emissions from 

the range of mobile sources: cars, light trucks, large 

trucks, buses, nonroad recreational vehicles (e.g., dirt 

bikes and snowmobiles), farm and construction equipment, lawn and garden equipment, marine engines, aircraft, and locomotives. 

OTAQ operates with an annual budget of more than 

$100 million and a staff of more than 350 technical, policy, and support personnel. Working out of EPA headquarters offices in Washington, DC, and the National 

Vehicle and Fuel Emissions Laboratory in Ann Arbor, 

Michigan, OTAQ’s primary activities include: 

■ Assessing mobile source-related air quality problems 

and developing and using sophisticated modeling 

tools to develop solutions and measure results. 

■ Establishing national standards to reduce 

emissions from on-road and nonroad mobile 

sources of pollution. 

■ Implementing national mobile source standards 

through certification processes and in-use monitoring strategies. 

■ Coordinating transportation and air quality policies 

with state, local, and federal agencies. 

■ Developing fuel efficiency programs and technologies to reduce the emission of greenhouse gases 

from the transportation sector. 

■ Developing clean and efficient automotive technologies and transferring them to the marketplace. 

■ Operating state-of-the-art models to support national, state, and local emission inventories. 

■ Managing international activities that leverage U.S. 

clean air experience and export technology solutions 

to developing countries. 

6 Office of Transportation and Air Quality — Progress Report 
The National Vehicle and Fuel 

Emissions Laboratory 

To carry out its mission, EPA established the National 

Vehicle and Fuel Emissions Laboratory in 1971 in 

Ann Arbor, Michigan—near the birthplace of the automobile industry and home to some of the world’s most 

advanced vehicle manufacturing, testing, and research 

facilities. Since its founding, the Lab has been at the 

forefront of developing clean automotive technology and 

designing programs to reduce and prevent air pollution. 

The Lab’s original mission was to test cars, light trucks, 

and heavy-duty engines to make sure they met established emission and fuel economy standards before 

entering mass production. While this work remains a 

core function, the Lab is now recognized as a leader in 

advanced testing and automotive technology. 

The Lab is also responsible for: 

■ Determining whether vehicles and engines comply 

with emission standards and fuel economy requirements. 

■ Testing fuels as well as highway and nonroad vehicles and engines to verify compliance with regulations designed to reduce emissions. 

■ Researching, evaluating, and developing advanced 

technologies for controlling emissions, as well as 

developing new strategies for improving fuel efficiency. 

The Lab has recently undergone extensive modernization and is now home to some of the most sophisticated instrumentation systems for emissions measurement in the world. EPA can now test more types of 

vehicles and engines under a broader range of operating 

conditions than ever before. For example, the Lab has 

instruments capable of accurately measuring emissions 

from the newest, ultra low-emitting Tier 2 vehicles, along 

with post-2007 heavy-duty engines and hydrogen-fueled 

(fuel cell) vehicles. This facility also houses the first fourWhat is a Dynamometer?

A dynamometer functions as a treadmill for vehicles. 

Vehicles on a dynamometer run on rollers to simulate 

driving conditions so that technicians can measure 

tailpipe emissions. 

wheel drive dynamometer site in the nation, specifically 

designed for certification testing of a wide range of vehicles, including four-wheel drive vehicles, chassis-certified 

heavy-duty vehicles, and hybrids. 

As new needs arise, the Lab will continue to maintain 

its position as a global leader in emissions testing and a 

resource to other nations as they develop stronger emission standards and associated testing requirements. 

Office of Transportation and Air Quality — Progress Report 7 
Clean Cars and Fuels 

Pairing Engine Technology Innovations with Cleaner Fuels 


for Optimal Results 

For more than 30 years, EPA has been working to 

reduce emissions from passenger vehicles. These 

efforts were accelerated with the passage of the 

1990 Clean Air Act Amendments. By the mid-1990s, EPA 

had set new emission standards for vehicles, developed 

a process to allow states to seek even further reductions, and implemented new controls on fuel quality. 

Together these actions dramatically reduced vehicle 

emissions and paved the way for the Agency to implement even more stringent regulations, known as the 

Tier 2 vehicle standards. 

EPA’s first action following the passage of the 1990 Clean 

Air Act Amendments was to implement the new tailpipe 

standards set by Congress. This regulation, called the 

Tier 1 standards, required auto manufacturers to meet 

new emission standards, which reduced overall nitrogen 

oxide emissions by up to 70 percent and particulate matter emissions by 54 to 69 percent, depending on the 

vehicle. Manufacturers began to meet these standards 

in 1994—the same year that EPA also phased in requirements that new cars be equipped with onboard diagnostic (OBD) systems to alert drivers to malfunctioning 

emission control equipment. 

8 Office of Transportation and Air Quality — Progress Report 
National Low Emission 

Vehicle Program 

I

n 1997, EPA negotiated an agreement between states, 

auto manufacturers, and environmental groups to 

allow seven Northeast states to surpass the Tier 1 standards. Under the resulting voluntary agreement, called 

the National Low Emission Vehicle (NLEV) program, auto 

manufacturers voluntarily agreed to produce vehicles 

that were 70 percent cleaner than average Tier 1 cars. 

Tier 1, NLEV, and RFG:


An Emissions Success Story


As of 2003, these important programs together eliminated 

over 2.2 million tons and over 21,000 tons of harmful 

emissions of NOx and PM respectively each year. 

The RFG program alone prevents 24,000 tons of toxic air 

pollutants, as well as 100,000 tons of other smog-forming 

air pollution, each year. 

Cleaner Fuels 

I

n the 1990 Clean Air Act Amendments, Congress 

included fuel along with vehicle technology as a 

potential source of emission reductions. In particular, 

Congress asked EPA to use fuels as an additional control strategy in areas with poor air quality or unique seasonal conditions. For example, carbon monoxide forms 

more easily in cold weather and at high altitudes, where 

diminished oxygen in the air results in less complete 

combustion. Denver pioneered a wintertime oxygenate 

program in the 1980s, requiring its gasoline to contain 

an oxygenated additive, such as ethanol. Significant 

reductions in carbon monoxide were achieved. This success was reflected in the 1990 Amendments with the 

requirement that carbon monoxide nonattainment areas 

implement similar programs. 

Similarly, EPA’s highly successful “reformulated” gasoline 

(RFG) program mandated cleaner-burning fuel for areas 

with the worst smog pollution. While initially mandated in 

nine metropolitan areas with the worst smog, 17 states 

Office of Transportation and Air Quality — Progress Report 

and the District of Columbia currently use RFG, either to 

comply with the Clean Air Act or on a voluntary basis. 

Today, about 30 percent of the gasoline sold in the 

United States is reformulated, and, as a result, roughly 

75 million Americans are breathing cleaner air. 

The Tier 2 Program: A New 

Generation of Vehicle 

and Fuel Standards 

The Tier 2 Vehicle and Gasoline Sulfur Program represents a new approach to EPA’s pollution control 

strategies for motor vehicles. Tier 2 addresses fuels and 

engines as one interrelated system. This cost-effective 

approach was found to be so successful that EPA later 

applied it to the landmark Heavy-Duty Diesel and the 

Nonroad rules. 

Tier 2 requires manufacturers to produce vehicles that 

emit significantly less harmful emissions than cars and 

light trucks produced even as recently as model year 

2003. Because sulfur in gasoline, like lead, is a fuel contaminant that inhibits the function of advanced catalytic 

converters, Tier 2 also requires refiners to reduce sulfur 

levels by 90 percent. 

Under Tier 2, vehicle regulations were applied equally for 

the first time—so that even the largest SUVs, pickup 

trucks, and vans must meet the same national emission 

standards as cars. Under Tier 2, vehicles and fuels are 

treated as a single system, so that the cleaner vehicles 

run on the cleaner fuels. These standards apply regardless of whether vehicles operate on gasoline, diesel 

fuel, or alternative fuels. 

9 
Tier 2’s Lasting Public Health Effects


EPA estimates that a national fleet of Tier 2 vehicles will 

prevent annually: 

■ 683,000 missed workdays from pollution-related 


illnesses


■ 4,300 premature deaths 

■ 10,000 cases of chronic and acute bronchitis 

■ Tens of thousands of respiratory problems 

Tier 2’s success was accomplished by fostering creative, 

effective partnerships to secure widespread support 

from a diverse group of stakeholders, including the automobile industry, the oil industry, states, and environmental groups. Because Tier 2 includes an incentive for 

companies to meet Tier 2 pollution reductions quickly 

and sooner than required, the auto industry began producing a significant number of very clean vehicles earlier 

than required by the program—despite the challenging 

technical requirements and implementation schedule. 

The refining industry is also successfully completing the 

process, reducing sulfur levels by 90 percent in U.S. 

gasoline. 

The health, environmental, and economic benefits of 

the program are extraordinary. Cars, SUVs, pickup 

trucks, and vans manufactured under today’s Tier 2 

standards are 77 to 95 percent cleaner than 2003 cars 

and trucks. As more of these cleaner vehicles enter 

the national fleet, harmful emissions will continue to 

drop. While Tier 2 will cost consumers about $70 to 

$250 more per compliant vehicle (depending on size), 

the new standards will deliver more than $25 billion 

per year in air quality and health improvements. 

Protecting Fuel Quality 

I

n addition to setting fuel standards, EPA is also 

responsible for protecting overall fuel quality by regulating the use of additives and detergents. 

Manufacturers must register both fuels and additives 

prior to their introduction into commerce. Registration 

involves providing a chemical description of the fuel or 

additive along with certain health effects data. OTAQ 

uses the information to identify fuels and additives 

whose emissions might pose an unreasonable risk to 

public health, thus meriting further investigation and/or 

regulatory action. In the case of detergent additives, 

EPA ensures that these additives keep fuel injectors 

and intake valves clean, which ultimately improves the 

combustion process and reduces emissions. Currently, 

EPA has approximately 360 fuels and 5,500 additives 

registered. The registration of detergents alone 

reduces 600,000 tons of carbon monoxide, hydrocarbons, and nitrogen oxide emissions each year. 

10 Office of Transportation and Air Quality — Progress Report 
Empowering the Public 

EPA also provides consumers with environmental information about vehicles so they can make informed decisions when buying a vehicle. For example, OTAQ 

developed and maintains the Green Vehicle Guide 

(www.epa.gov/greenvehicles). This Web-based tool 

helps consumers find the cleanest, most fuel-efficient 

vehicle that meets their needs. Users can select a specific vehicle to see its performance on a scale of 0 to 

10, with 10 being the best, and compare it to others. 

Today, the Green Vehicle Guide is one of OTAQ’s most 

visited Web sites. Over the past year, the site has 

received an average of nearly 1 million hits per month. 

Improving Fuel Economy Estimates

maintains the nation’s most extensive database on 

vehicle fuel economy. The annual Fuel Economy Trends 

report, which EPA has issued every year since 1975, 

includes detailed information on each manufacturer’s 

fuel economy and summarizes key trends in automotive technology. 

EPA is revising the way it calculates the fuel economy 

estimates posted on all new vehicles. Working with consumer groups and auto manufacturers, EPA is developing 

new procedures that will better account for real-world 

driving conditions. The goal is to ensure that the fuel economy information for all new vehicles reflects actual vehicle performance on the road. 

EPA, along with the Department of Energy, also publishes the Fuel Economy Guide booklet every year. It 

contains information about vehicles’ fuel economy so 

consumers can make clear comparisons. EPA also 

Office of Transportation and Air Quality — Progress Report 11 
Clean Trucks, Buses, and Diesel Fuels


Cleaning Up America’s Transportation Workhorses 

The nation’s more than 2 million heavy-duty trucks 

and buses play an essential role in the U.S. economy and transportation network. They are also a 

major source of nitrogen oxides and particulate matter. 

These emissions create significant health problems for 

millions of Americans. For this reason, one of OTAQ’s 

major goals is to clean up heavy-duty vehicles and the 

fuels that power them. 

Since the 1990 Clean Air Act Amendments, OTAQ has 

taken several critical steps to reduce pollution from 

heavy-duty vehicles. For example, in 1993, a 500 parts 

per million (ppm) limit on sulfur in diesel fuel took effect. 

As of 2004, truck and bus manufacturers were required 

to meet more stringent emission standards—an action 

that will reduce particulate matter by 55,000 tons per 

year. The standards required gasoline trucks to be 78 

percent cleaner and diesel trucks to be more than 40 

percent cleaner than existing models. These standards 

represented a more than 40 percent reduction in emissions of nitrogen oxides, as well as reductions in hydrocarbons, from diesel trucks and buses. These standards 

laid the groundwork for the comprehensive 2007 Clean 

Diesel Truck and Bus Program. 

12 Office of Transportation and Air Quality — Progress Report 
The 2007 Clean Diesel Truck 

and Bus Program 

The 2007 Clean Diesel Truck and Bus Program is 

EPA’s latest and most ambitious strategy to reduce 

emissions from heavy-duty vehicles. This program pairs 

engine technology changes with fuel changes to achieve 

significant reductions at the least cost to society. 

Under the new standards, fuel sulfur will be cut from 

the current level of 500 ppm to 15 ppm—a 97 percent 

reduction. This step will enable advanced emission conNew Standards Yield Many Benefits

The 2007 Clean Truck and Bus Program’s standards will 

mean huge reductions in ozone and ambient particulate 

matter, which are major air pollutants. In 2030, these 

reductions will prevent annually: 

■ 8,300 premature deaths 

■ More than 9,500 hospitalizations 

■ 1.5 million work days lost 

The total health benefits are worth more than $70 billion 

each year, with costs of only $4 billion. 

trol technologies to be installed that virtually eliminate 

particulate matter and nitrogen oxide emissions from 

diesel engines. These standards were successfully 

developed in partnership with oil and engine companies, 

state and local governments, and the public health and 

environmental community. 

The combination of cleaner vehicles and cleaner fuels 

will result in dramatic environmental improvements. By 

2030, EPA expects annual reductions of 2.6 million tons 

of nitrogen oxides, 115,000 tons of hydrocarbons, and 

nearly 17,000 tons of air toxics. EPA’s new program will 

result in particulate matter and nitrogen oxide emission 

levels that are 90 percent and 95 percent below today’s 

levels, respectively. These enormous air quality improvements will translate into significant health benefits for 

the American public. 

Office of Transportation and Air Quality — Progress Report 13 
Clean Nonroad (Off-Highway) 

Engines and Fuels 

Achieving Reductions from Nonroad Mobile Sources, 

Large and Small 

From lawnmowers and boats to tractors and quarry tribute to poor air quality in a distant city or national 

trucks, nonroad vehicles, sometimes referred to park. Worse, these machines often operate in close 

as “off-highway” vehicles, are America’s work proximity to construction workers, farm families, and 

engines and play engines. But like trucks and buses, nearby residents, emitting pollutants directly into peononroad diesel engines are also a significant source of ple's breathing space. 

harmful particulate matter and nitrogen oxides, which 

contribute to ground-level ozone (smog) and other perva- In the 1990 Clean Air Act Amendments, Congress 

sive air quality problems. These pollutants can travel directed EPA to study emissions from all nonroad 

hundreds of miles so that a rural farm tractor can con- engines and vehicles, and to set emission standards if 

14 Office of Transportation and Air Quality — Progress Report 
these sources were found to cause or significantly contribute to air pollution. In the early 1990s, EPA focused 

on completing this emission study and building consensus around the need for pollution controls. 

The Agency then set to work developing the first-ever 

emission standards for nonroad engines. Because of the 

wide variety of nonroad engines, EPA has had to tailor 

its rulemakings to both engine size and purpose. OTAQ 

also issued these regulations in a series of steps, or 

“tiers,” in order to take advantage of advancements in 

control technology. For example, between 1995 and 

1999, OTAQ issued a series of regulations affecting lawn 

and garden equipment. A later rulemaking set standards 

for recreational vehicles (e.g., snowmobiles and all-terrain vehicles) and certain industrial equipment. Today, 

there are emission standards affecting virtually every 

type of nonroad engine—from chainsaws and snowmobiles to yachts and backhoes. 

Large Benefits from a “Small” Source

Together, EPA’s rules affecting lawn and garden equipment, fork lifts, and recreational vehicles will cut particulate matter and nitrogen oxide emissions by about 500,000 

tons per year. The recreational vehicle regulation alone 

will bring about an estimated $8 billion in annual health 

benefits by 2030. 

Large Nonroad Engines 

Pollution emitted by large nonroad diesel vehicles 

such as bulldozers, locomotives, and marine vessels 

has been a particular concern to the Agency. These highly durable engines can operate for decades and emit 

large amounts of nitrogen oxides, particulate matter, and 

air toxics, each of which contributes to serious public 

health problems. Over the last several years, OTAQ has 

developed a series of regulations to reduce emissions 

from these engines. These efforts were advanced significantly in 2004 with the completion of the Clean Air 

Nonroad Diesel Program. This landmark program 

achieves dramatic reductions from large nonroad 

Office of Transportation and Air Quality — Progress Report 

engines used in most construction, industrial, and agricultural equipment and sets the stage for comparable 

reductions from locomotives and marine vessels. 

Cleaning Up America’s 

Workhorses 

Like EPA’s regulation affecting heavy-duty trucks and 

buses, the Clean Air Nonroad Diesel Program integrates engine and fuel controls as a system to gain the 

greatest emission reductions. Engine standards take 

effect for most new engines in 2008 and final standards 

phase in starting in 2011, coinciding with the availability 

of the clean fuel. These standards will reduce particulate 

matter and nitrogen oxide emissions by 90 percent. 

In addition, new fuel requirements decrease the allowable levels of sulfur in fuel used in nonroad diesel 

engines, locomotives, and marine vessels by more than 

99 percent. These fuel improvements will create immediate and significant environmental and public health 

benefits by reducing particulate matter from engines in 

the existing fleet of nonroad equipment. They also make 

it possible for engine manufacturers to use advanced 

emission control technologies, similar to those upcoming for highway diesel trucks and buses. 

15

EPA’s Clean Air Nonroad Diesel Program:

A 40:1 Benefit-Cost Ratio

The long-term annual health benefits of this important program include the prevention of approximately: 

■ 6,000 children’s asthma-related emergency room visits 

■ 8,900 hospitalizations 

■ 12,000 premature deaths 

■ 15,000 heart attacks 

■ 280,000 cases of respiratory symptoms in children 

■ 1 million lost work days 

When fully implemented, the annual monetized health and 

welfare benefits of this program will exceed $80 billion, 

compared to implementation costs of $2 billion. 

The Clean Air Nonroad Diesel Program marks the first 

time a major mobile source regulation was not legally 

challenged in court. This is a tribute to OTAQ’s extensive 

collaboration with the nonroad industry, environmental 

and public health groups, and state governments. These 

groups committed to help EPA design a solution that 

was good for the environment and good for business. 

Keeping Locomotives on Track 

for Reductions 

About 25,000 diesel-electric locomotives currently 

operate in the United States, and in general they 

produce extremely high levels of pollution. Because a 

typical locomotive lasts 40 years or more, the turnover 

to new locomotive models takes decades. In 1997, 

OTAQ established standards requiring that current locomotives be made cleaner when they are remanufactured 

to “as new” condition—a step that will cut nitrogen 

oxide emissions for much of the existing locomotive fleet 

by 33 percent between 2007 and 2009. This rule also set 

the first emission standards for newly manufactured 

locomotives. 

In May 2004, EPA announced its intent to propose even 

more stringent locomotive engine emission standards. 

These standards would require the use of advanced 

emission-control technologies similar to those required 

by the Clean Air Nonroad Diesel Program. The availability 

of clean nonroad diesel fuel required under the new 

nonroad fuel standards will enable the use of this technology on locomotive engines. 

Managing Marine Vessels 

Unlike land-based diesel vehicles, many large marine 

vessels travel the globe. For this reason, EPA has 

used two separate processes to achieve reductions. 

For large ocean-going vessels, EPA has worked with the 

International Maritime Organization (IMO) to set emission standards. The IMO was established in 1948 under 

the United Nations to address safety, navigation, and pollution prevention for ships engaged in international trade. 

Current EPA standards are equivalent to the levels determined by the IMO. OTAQ is also considering a second 

tier of standards that would reflect additional reductions 

that can be achieved through engine-based controls. 

For smaller vessels, EPA has adopted regulations similar 

to land-based nonroad and locomotive engines. The current standards take effect starting between 2004 and 

2007, depending on the size of the engine, and will 

reduce nitrogen oxide emissions by about one-third and 

particulate matter emissions by about 25 percent. As 

with locomotives, EPA has announced its intention to 

propose more stringent emission standards for all new 

commercial, recreational, and auxiliary marine diesel 

engines, except the very large engines used for propulsion on deep-sea vessels. 

16
 Office of Transportation and Air Quality — Progress Report
Certification and Compliance 


Keeping Vehicles Clean 

I

mplementing regulatory programs is an important 

part of EPA’s overall air quality strategy. OTAQ not 

only works to ensure that vehicles are designed to 

meet emission standards when they first enter the market, but also that they continue to meet those standards 

throughout their useful life—which, for most passenger 

vehicles, is more than 100,000 miles. 

Because the vast majority of cars and trucks on the 

road today are not new, and therefore do not meet 

EPA’s Tier 2 standards, OTAQ expends significant effort 

to ensure that vehicles are in compliance with the 

emission standards. 

To help vehicles stay clean, EPA works with state agencies to implement inspection and maintenance (I/M) programs in areas with serious air pollution problems to 

ensure that emission control systems continue to operate optimally. Still in place today, I/M programs identify 

and clean up the most polluting vehicles by alerting 

motorists when repairs are needed. 

Office of Transportation and Air Quality — Progress Report 17 
Keeping New Cars Clean in 2004


■ Manufacturers conducted approximately 2,000 emissions tests to show that their new vehicles meet the 

emission standards. 

■ EPA conducted random and selective test audits on 

more than 150 car models and found 15 that had emissions problems. Manufacturers corrected these problems before the vehicles were mass-produced. 

■ Manufacturers voluntarily recalled 2.7 million vehicles 

due to 35 emission-related problems. These recalls will 

prevent the release of thousands of tons of pollutants 

into the air. 

Testing Emissions Before 

Mass Production 

Before vehicles are mass-produced, EPA requires 

auto manufacturers to test prototype vehicles to 

ensure they will minimize emissions throughout their 

useful life. EPA audits these tests to confirm that they 

are accurate and reliable. If the tests reveal a problem, 

the manufacturer must fix it and demonstrate that the 

modified prototype will pass the test before mass production can begin. After completing the tests and other 

analyses, prototypes that pass receive a certificate of 

conformity from EPA, which enables the manufacturer 

to sell vehicles of similar design in the United States. 

This program prevents pollution by ensuring that all new 

cars are designed to meet emission requirements 

before they are even produced and sold. 

Post-Production Emissions 

Monitoring 

Once vehicles are on the road, EPA requires manufacturers to report any emission-related defect that 

is found on 25 or more vehicles for any given model 

year. OTAQ reviews these defect reports to assess the 

seriousness of the defect and the manufacturer’s solutions. These reports are one of the most useful tools to 

help identify potential problems with vehicles warranting 

further attention. 

Both OTAQ and manufacturers test customer-owned 

vehicles for emission problems. In addition to random 

selections, OTAQ selects vehicles for testing by taking 

into account information gleaned through its pre-production audits, manufacturer defect reports, and consumer 

tips. In response to data collected from these tests, virtually all of the emissions-related vehicle recalls over the 

past decade have come from voluntary actions by 

manufacturers. 

Engine Testing and Monitoring 

OTAQ also works closely with diesel truck, bus, and 

other engine manufacturers to ensure that these 

engines meet emission standards and stay clean 

throughout their useful lives. Similar to the vehicle certification process, engine manufacturers perform emission tests on their engines and submit certification data 

to EPA for review. OTAQ then analyzes the emissions 

data and assesses whether the engine is clean enough 

to meet the required specifications. If an engine meets 

the standards, OTAQ issues a certificate of conformity, 

which enables the engine to be sold within the United 

States. In 2004, OTAQ issued a record number—approx18 Office of Transportation and Air Quality — Progress Report 
imately 1,800—certificates of conformity for heavy duty 

and nonroad engines, including marine engines and 

lawnmowers. In addition, OTAQ performs several hundred emissions tests each year on heavy-duty diesel 

trucks and equipment in normal operating conditions to 

see how performance and emissions are affected. 

Marathon Tests

OTAQ tests engines in a variety of conditions and settings to 

gain a better understanding of how a variety of factors 

affect an engine’s emissions performance. In 2004, OTAQ 

conducted eight “marathon tests,” so called because of the 

extreme distances covered. These tests totaled more than 

4,000 miles and provided about 75 hours worth of test data. 

Results from these tests help OTAQ determine how factors 

such as altitude, temperature, terrain, and driving habits 

affect an engine’s emissions while the vehicle is in use. 

Starting in 2007, EPA will require a manufacturer-run 

emissions testing program for heavy-duty diesel trucks. 

Under this program, heavy-duty truck manufacturers will 

start conducting their own tests using a Portable 

Emissions Measurement System in 2005 as part of a 

pilot program, complementing EPA’s own testing. The 

program will expand nationwide with 2007 model year 

diesel trucks. This cooperative effort among EPA, the 

state of California, and industry represents a significant 

advance in helping to ensure that the benefits of more 

stringent emission standards are realized under realworld driving conditions. 

Portable Emissions Measurement System

(PEMS)

PEMS, a breakthrough technology that OTAQ helped 

develop, consists of miniaturized versions of the same 

analyzers that OTAQ uses in labs. These portable systems 

are installed in selected vehicles driven under real-world 

conditions and collect a wide variety of information, 

including: 

■ Emissions concentrations of nitrogen oxides, carbon


dioxide, and non-methane hydrocarbons.


■ Exhaust mass flow rate so that grams of emissions can 

be calculated. 

■ GPS information so that grams-per-mile emissions can 

be calculated. 

■ Engine electronic control module information so that


grams-per-brake horsepower-hour emissions can be


calculated.


■ Ambient weather information. 

This information is used to build and verify OTAQ’s emissions inventory models, confirm in-use compliance of vehicles and engines, and determine real-world fuel economy. 

The success of PEMS in vehicles has led experts to consider adapting it for emissions testing of large engines 

such as locomotive and marine engines, which are difficult 

to test in a lab. 

Office of Transportation and Air Quality — Progress Report 19 
The National Clean Diesel Campaign


Cleaning Up Today’s Diesel Engines 

Reducing emissions from diesel engines is one of 

the most important air quality challenges facing 

the country. Even with EPA’s new heavy-duty 

highway engine standards, over the next 20 years millions of diesel engines already in use will continue to 

emit large amounts of nitrogen oxides and particulate 

matter, both of which contribute to serious public health 

problems. These problems are manifested by thousands 

of instances of premature mortality, hundreds of thousands of asthma attacks, millions of lost work days, and 

numerous other health impacts. 

In order to maximize reductions from all diesel engines, 

EPA launched a comprehensive initiative called the 

National Clean Diesel Campaign. The Campaign uses a 

multi-pronged approach. First, the Campaign is committed to the successful implementation of the 2007 Clean 

Diesel Truck and Bus Program and the Clean Air Nonroad 

Diesel Program. Second, EPA will develop new emissions requirements for locomotives and marine diesels, 

including large commercial marine engines. Lastly, to 

address engines already in use today that are not subject to the new regulations, the Campaign is promoting 

20 Office of Transportation and Air Quality — Progress Report 
the reduction of emissions through a variety of 

cost-effective and innovative strategies, including 

switching to cleaner fuels and “retrofitting” engines 

through the addition of control devices. The Energy 

Policy Act of 2005 also includes grant provisions and 

other incentives to help facilitate voluntary clean diesel 

actions nationwide. 

Sector-Based Voluntary 

Programs Leading the Way 

The National Clean Diesel Campaign is focused on 

leveraging local, state, and federal resources to 

install cost-effective retrofit technologies on diesel 

engines, adopt best practices, develop demonstration 

projects, and track and report results. More than 500 

partners are involved in approximately 220 voluntary 

projects nationwide. 

Distribution of National Clean Diesel Campaign Projects in 2004

The partnerships are organized around sectors that provide the best opportunity to obtain significant reductions, produce emissions with immediate impacts on 

public health, or comprise a relatively large portion of 

the country’s diesel emissions inventory. 

Office of Transportation and Air Quality — Progress Report 21 
Clean Ports USA Demonstrates Success


The Port of Houston Authority, the Port of Tacoma, and 

Massachusetts Port Authority have received EPA grant 

funding to demonstrate how retrofitting trucks, yard equipment, straddle carriers, and rubber-tired gantry cranes 

with diesel oxidation catalysts and using ultra low-sulfur 

diesel and emulsified diesel fuel at terminals reduces local 

air pollution. 

The National Clean Diesel Campaign partnerships 

include: 

■ Clean School Bus USA. Partners with school 

transportation officials and local and state governments to reduce diesel pollution from the nation’s 

school bus fleets. 

■ Clean Ports USA. Helps reduce diesel emissions 

at U.S. ports. 

■ Clean Construction USA. Encourages the use 

of retrofit technologies and engine replacement in 

construction equipment at major construction 

projects in areas that do not meet the national air 

quality standards. 

■ Clean Agriculture USA. Joins with the farming 

community, government agencies, and nongovernmental organizations to promote clean diesel strategies, including biofuels and renewable fuels across 

the country. 

■ SmartWay Transport. Partners with both shippers and carrier fleets to create highly fuel-efficient, 

low-emissions trucks that deliver freight in the 

United States. Companies involved with the program include Federal Express, UPS, IKEA, and The 

Home Depot. 

Regional Efforts 

Acritical component of the National Clean Diesel 

Campaign is to promote regional initiatives that use 

a proactive, incentive-based approach to achieve results. 

Regional partners agree to collectively leverage additional funds and take a local approach to reducing harmful 

emissions. One of the first such efforts is the West 

Coast Diesel Emissions Reductions Collaborative, in 

which a number of partners are working together to 

reduce air pollution emissions from diesel engines along 

the West Coast. In addition to EPA, partners include: 

■ U.S. Department of Agriculture/Natural Resource 

Conservation Service 

■ U.S. Department of Energy 

■ U.S. Department of Transportation 

■ State, local, non-profit, and private sector partners 

from California, Alaska, Washington, and Oregon 

■ Canada and Mexico 

Other regional collaboratives are working to reduce 

diesel emissions in their respective regions. For example, the Midwest Diesel Initiative is a new public-private 

effort to reduce diesel emissions along major transportation corridors and in various sectors, including trucking, 

locomotive, construction, and ports, with emphasis on 

urban areas. The Northeast Diesel Collaborative encourages participants to engage in projects that will reduce 

transportation-related air pollution to help address high 

asthma rates. 

22 Office of Transportation and Air Quality — Progress Report 
Transportation and Global Climate Change


Tackling Challenges with Technical Innovations and Partnerships


While the transportation sector is crucial to the 

nation’s economy and personal mobility, it is 

also a significant source of greenhouse gas 

emissions. In 2002, almost one-third of all greenhouse 

gases released in the United States came from the transportation sector, mostly from carbon dioxide released 

through the combustion of diesel and gasoline fuels. 

OTAQ is working both to improve the Agency’s knowledge about the transportation sector’s contribution to 

greenhouse gas emissions and to reduce the amount of 

greenhouse intensity of this sector. These efforts are 

focused in three areas: 

■ Developing new automotive technologies that 

improve fuel efficiency. 

■ Reducing nationwide fuel consumption through voluntary programs that encourage Americans to drive 

wisely and trucking companies to enhance the fuel 

efficiency of their fleets. 

Office of Transportation and Air Quality — Progress Report 23 
■ Developing inventories and models to help track 

emissions and evaluate the potential costs and benefits of reducing the greenhouse gas intensity of the 

transportation sector. 

These efforts are an important part of the 

Administration’s broader strategy to reduce greenhouse 

gas emissions through voluntary programs and investments in emerging technologies. 

Developing Clean Automotive 

Technology 

Engineers at OTAQ’s National Vehicle and Fuel 

Emissions Lab are working to develop a new generation of clean, efficient vehicles. To date, EPA has 

received 29 advanced patents in the fields of engine 

design and automotive technology and has 19 more 

patents pending. To transfer this technology to the marketplace as quickly as possible, OTAQ has developed 

formal partnerships with private companies like Ford 

Motor Company and Eaton Corporation to help test and 

commercialize EPA’s technologies. Currently, OTAQ is 

focused on developing two promising technologies— 

hydraulic hybrids and clean diesel engines. 

Hydraulic Hybrid Vehicle 

Research 

OTAQ’s automotive engineers are leading the nation in 

the development of hydraulic hybrid vehicles. This technology uses a hydraulic energy storage and propulsion 

system to capture and store energy normally wasted in 

vehicle braking. This energy is used to help propel the 

vehicle during the next acceleration. 

OTAQ has focused its efforts on improving two kinds of 

hydraulic hybrids: “mild” and “full.” A mild hydraulic 

hybrid uses hydraulic components that are “added on” 

to a conventional vehicle engine system and do not fundamentally change the way the vehicle is powered. A 

full hydraulic hybrid completely integrates the hydraulic 

components into the powertrain system and can thus 

Fuel Efficiency Facts


■ Since 1997 fuel economy for passenger vehicles has 

been relatively constant, ranging from 20.6 to 21 miles 

per gallon (mpg). 

■ Model year 2005 vehicles are estimated to average 21 

mpg. This is 0.2 mpg higher than 2004, but 5 percent 

below the fleet-average fuel economy peak value of 

22.1 mpg achieved in 1987. 

■ This year, cars and light trucks are each projected to 

account for 50 percent of vehicle sales. 

maximize the full potential of the energy storage and 

propulsion systems of the technology. 

Using mild hydraulic hybrid technology, OTAQ recently 

built a delivery truck that operates at 25 to 30 percent 

more miles per gallon than a comparable standard delivery truck. OTAQ is now building a full hydraulic hybrid 

delivery truck with UPS and other partners to allow a 

fuller demonstration and evaluation of the technology. 

This vehicle is expected to attain 60 to 70 percent more 

miles to the gallon than comparable delivery trucks. 

OTAQ also built the world's first full hydraulic hybrid 

SUV, which averages 55 percent more miles per gallon 

than its conventional counterparts. 

Clean Diesel Combustion 

Engine 

Clean diesel vehicles, together with hybrids, offer promising near-term improvements in fuel economy and 

greenhouse gas reductions. OTAQ is working with 

International Truck & Engine Corporation and Ford Motor 

Company to develop an extremely efficient, clean, and 

cost-effective diesel combustion engine for cars, SUVs, 

and light pickup trucks. In 2004, OTAQ developed a 

clean diesel combustion engine and deployed it successfully in a minivan. This is a promising technology for 

reducing nitrogen oxides—without the need for any 

exhaust treatment for nitrogen oxides. Results so far 

24 Office of Transportation and Air Quality — Progress Report 
also indicate that clean diesel combustion engines can 

maintain the excellent fuel economy, performance, and 

reliability of conventional diesel engines. 

Reducing Fuel Consumption 

and Emissions 

Reducing fuel consumption is a win-win situation for 

business, private individuals, and the environment. 

Fewer gallons of fuel burned means reduced greenhouse gas emissions, lower fuel costs, and less dependence on imported oil. OTAQ’s voluntary programs help 

reduce fuel consumption in two key sectors—freight 

transport and workplace commuting. 

SmartWay Transport® 

Announced in February 2004, SmartWay is a voluntary 

partnership between various freight-industry sectors and 

EPA that establishes market-based incentives for fuel 

efficiency improvements and greenhouse gas emission 

reductions. By 2012, this initiative aims to eliminate 33 

million to 66 million metric tons of carbon dioxide emissions and up to 200,000 tons of nitrogen oxide emissions per year. At the same time, the initiative will result 

in fuel savings of up to 150 million barrels of oil annually. 

Approximately 160 shipping, truck, and rail companies 

Reducing Unnecessary Idling

Reducing unnecessary idling is a major component of EPA’s 

SmartWay program. As a part of their daily routine, countless 

drivers sit and idle their vehicles, wasting valuable fuel and 

money and polluting the air. SmartWay partners are adopting 

innovative idle reduction technologies, taking advantage of 

proven systems that provide drivers with power, heat, and air 

conditioning without using the engine. 

To date, there are 50 stationary anti-idling projects, and 

mobile technology has been installed on nearly 20,000 

trucks. These efforts will save nearly 40 million gallons of 

diesel fuel every year and reduce more than 440,000 tons 

of carbon dioxide, 7,000 tons of nitrogen oxides, and nearly 

200 tons of particulate matter annually. 

Office of Transportation and Air Quality — Progress Report 

are enrolled in the program—representing more than 

255,000 trucks. 

As a partner, each company creates an action plan 

detailing the technologies and policy measures it will 

use to reduce fuel consumption, greenhouse gas emissions, and air pollution. These measures include reducing truck idling, employing advanced aerodynamic features on the tractors and trailers of their trucks, replacing traditional tires with next-generation super single 

tires, and increasing the amount of freight delivered by 

rail. As SmartWay partners work towards achieving 

these environmental goals, they are also improving their 

corporate bottom line. Most of the innovative technologies and strategies implemented in SmartWay will quickly pay for themselves in just a few years and continue to 

save these companies money for years to come. 

25 
Best Workplaces for 

CommutersSM Tackle the 

Daily Commute 

I

n addition to being stressful for workers, the daily 

commute represents another significant source of 

emissions. In 2002 alone, 5.7 billion gallons of fuel were 

wasted in traffic congestion—more than 500 times the 

amount of oil spilled by the Exxon Valdez—unnecessarily 

releasing 50 million tons of carbon dioxide into the 

atmosphere. 

In response, EPA is working with employers across the 

country to reverse the trend of longer, single-occupancy 

vehicle commuting. OTAQ has created a list of the Best 

Workplaces for Commuters to formally recognize 

employers that offer outstanding commuter benefits— 

from providing free transit passes to offering the flexibility of working from home. More than 1,100 employers 

representing more than 2 million workers have made 

the list so far. In 2004, these exemplary commuter benefits prevented the release of more than 900,000 metric 

tons of carbon dioxide into the air. Each year, these 

employers also reduce the need for roughly 275,000 

parking spaces, reduce the number of miles driven by 

more than 2 billion, and save more than 100 million gallons of gasoline. 

Making an Impact with the FORTUNE 500

In September 2004, EPA released the inaugural list of Best 

Workplaces for Commuters from the FORTUNE 500 companies. The announcement was big news: more than 240 

media outlets across the country provided positive media 

exposure and recognition in 340 stories to these commuterfriendly companies. In October 2005, a second list of nearly 

90 FORTUNE 500 companies was released. These companies include many household names, such as Intel, 

Microsoft, Boeing, and Nike, and their efforts are helping to 

reduce annual gasoline usage by 30 million gallons. 

Developing New Tools and 

Models 

The third component of OTAQ’s climate-related work 

is to provide information on the impact of the transportation sector to total greenhouse gas emissions and 

to help evaluate the potential of technology advancements and alternative fuels to help reduce emissions 

from this sector. These efforts involve a range of activities, including: 

■ Calculating greenhouse gas emissions from the 

transportation sector for inclusion in EPA’s Inventory 

of U.S. Greenhouse Gas Emissions and Sinks. This 

information provides a common and consistent basis 

for policy analysis, and supports the development of 

cost-effective greenhouse gas mitigation strategies. 

■ Evaluating economic models to ensure that these 

models incorporate the most recent transportationrelated information and accurately evaluate the interaction between transportation and other sectors of 

the economy. 

■ Assessing the potential of vehicle technologies, 

including advanced gasoline, diesel, and gasoline 

hybrids, to significantly and cost-effectively improve 

vehicle fuel economy and reduce U.S. dependence 

on foreign oil. This work also considers potential savings to consumers in the form of reduced fuel and 

operating costs. EPA is also examining the greenhouse gas and criteria pollutant impacts of various 

renewable fuels. 

26 Office of Transportation and Air Quality — Progress Report 
International Programs


Working with the World 

Nearly every country in the world suffers from air 

pollution, and each year more and more of it is 

generated from cars, trucks, and other mobile 

sources. Huge growth in population and the number of 

vehicles on the road is the new norm in most large 

cities in developing countries. While these vehicles have 

led to greater mobility, they have also created severe air 

pollution problems. And, like so many other environmental problems, air pollution doesn’t stop at borders. 

Working in conjunction with other offices at EPA and in 

the federal government, OTAQ has been engaged in 

international sustainable transportation efforts to reduce 

air pollution. Building on its successes in the United 

States, OTAQ offers technical and policy assistance, 

shares its 30 years of experience, and sponsors clean 

fuel and vehicle projects with partners in four continents. Bilateral discussions and cooperation between 

the United States and other countries are an important 

part of this effort. 

A Global Player 

EPA is an active participant in several key international 

environmental efforts including the United Nations’ 

World Forum for Harmonization of Vehicle Regulations 

and the Partnership for Clean Fuels and Vehicles. At the 

UN’s World Forum, OTAQ has played a leadership role in 

Office of Transportation and Air Quality — Progress Report 27 
Air Quality and Health Across the Globe

■ 85 percent of the largest cities in developing countries 

have unacceptable air quality. Many cities in Asia, 

such as Bangkok, are faced with levels of suspended 

particulate matter that are at least twice as high as 

international health guidelines recommend. The primary reasons: an abundance of vehicles without modern emission control standards and the low quality of 

available fuel. 

■ In China, the vehicle population doubled between 2002 

and 2004 and contributes 79 percent of the country’s air 

pollution. About 1,000 vehicles a day are added in 

Beijing alone. 

■ In Santiago, Chile, the transportation sector is the primary source of air pollution, contributing 92 percent of 

the city’s carbon monoxide emissions, 71 percent of 

nitrogen oxide emissions, and 46 percent of volatile 

organic compounds. 

■ In Mexico City, the transportation sector is responsible 

for nearly all carbon monoxide emissions, more than 80 

percent of nitrogen oxides, and 40 percent of volatile 

organic compounds. 

the development of global technical regulations. This 

work is initially focusing on harmonizing test procedures 

for diesel engines and motorcycles. When adopted, 

these environmentally beneficial procedures will 

improve compliance determinations worldwide and 

allow developing countries to move more quickly to 

state-of-the-art emission standards, bypassing the years 

of development experienced in the United States and 

elsewhere. It will also reduce the costs of compliance 

for engine manufacturers. 

The Partnership for Clean Fuels and Vehicles (PCFV) was 

developed as one of the Bush Administration’s initiatives 

adopted at the World Summit on Sustainable 

Development in Johannesburg, South Africa in 2002. 

Through the PCFV, OTAQ works collaboratively with 

other countries, industry, and public health organizations 

to eliminate lead in fuels and reduce sulfur in gasoline 

and diesel fuels, leading to the introduction of clean 

vehicles and engines. The partnership helps establish 

demonstration projects that show how installing emission control equipment on diesel buses and trucks, 

along with using low-sulfur fuels, can reduce local air 

pollution cost-effectively. For example, in Mexico City, a 

group has installed emissions-reducing equipment on 30 

buses and trucks, which run on clean low-sulfur diesel 

imported from Texas. 

China and OTAQ: A Working Partnership

As in many other countries, the large increase of vehicles 

in China’s major cities has brought severe air pollution. In 

response, OTAQ and China’s State Environmental 

Protection Administration are working to improve fuel 

quality, enable cleaner new vehicles, and increase the 

compliance of vehicles that are on the road now. For 

example, OTAQ and China are working together to reduce 

sulfur in fuels and launch a retrofit demonstration project 

in Beijing. These projects are integral to Beijing’s 

Environmental Protection Bureau’s goal of significantly 

reducing air pollution before the 2008 Olympic Games. 

OTAQ has attracted many partners to work on these projects, including Harvard’s John F. Kennedy School of 

Government, Tsinghua University in Beijing, Energy 

Foundation China, Corning, Cummins, GM, and Ford. These 

partners are offering their expertise, consultation, equipment donations, funding, and other assistance. OTAQ anticipates that other groups will join in these efforts as well. 

28
 Office of Transportation and Air Quality — Progress Report
Looking Forward 

Toward a Cleaner Future 

There is no question that significant progress has 

been made in reducing the transportation sector’s impact on the environment. Tens of millions of tons of pollutants have already been reduced, 

with tens of millions of tons more reductions expected 

in the years to come. Cars, trucks, buses, and the full 

range of nonroad engines, such as construction and 

farm equipment, are cleaner than they have ever been, 

and there are regulations and standards in place to 

keep these sources clean well into the future. 

However, the nation still has notable challenges in 

meeting the health-based air quality standards, with 

more than 100 million people living in areas that are 

not attaining clean air quality levels. 

Therefore, OTAQ will continue its efforts to reduce the 

transportation sector’s impact on the environment. By 

setting and implementing cost-effective standards, establishing policies to address greenhouse gas emissions, 

developing and bringing innovative clean technologies to 

market, and expanding voluntary emission reductions 

programs, EPA will reduce harmful emissions and protect public health and the global environment. 

Future challenges for OTAQ include: 

■ Successfully implementing the ultra low-sulfur diesel 

fuel program, the 2007 Clean Diesel Truck and Bus 

Program, and the Clean Air Nonroad Diesel Program. 

Office of Transportation and Air Quality — Progress Report 29 
■ Develop proposals for a new generation of locomotive and large marine engine standards, as well as 

small-spark ignition engine standards. 

■ Address air toxic emissions from mobile sources. 

■ Implement provisions of the 2005 Energy Policy Act 

and the Transportation Act (SAFETEA-LU). 

■ Expand the National Clean Diesel Campaign. 

■ Move clean automotive technologies from the lab to 

the road. 

■ Develop, strengthen, and expand EPA’s innovative, 

market-based approaches to reduce fuel consumption and greenhouse gas emissions. 

■ Export EPA’s experience and U.S. technology to 

developing countries. 

■ Update models and other tools that provide assistance to state, local, and tribal governments in their 

efforts to achieve air quality goals. 

With the demand for transportation and related services 

growing every year, OTAQ’s work has never been more 

important. We look forward to reporting on these and 

other accomplishments in the next progress report. 

30 Office of Transportation and Air Quality — Progress Report 
Clean Transportation Milestones


1966

Congress requires minimal emission controls on all 

model year 1968 and later cars. 

1970

EPA is established by a Presidential Executive Order. 

Congress adopts the first major 

Clean Air Act, and gives the new 

Agency broad responsibility for regulating motor vehicle pollution. The 

law calls for 90 percent reductions 

in auto emissions and the phaseout 

of lead from gasoline. 

Approximately 89 million passenger cars are driven 

on 1.7 million paved roads in the United States. 

1971

The National Vehicle and Fuel Emissions Laboratory 

opens. 

1974

Congress adopts the Energy Policy Conservation Act, 

which establishes fuel economy standards for cars. 

1975

The first catalytic converters appear in vehicles. 

Unleaded gasoline is available in the United States for 

the first time. 

1980

Between 1976 and 1980, as the amount of lead in 

gasoline dropped by 50 percent, blood-lead levels in 

children dropped 37 percent. 

1981

New cars meet the amended Clean Air Act standards 

for the first time. Sophisticated three-way catalysts 

with on-board computers and oxygen sensors appear 

in most new cars. 

1983

Inspection and maintenance programs are established 

in 64 cities, requiring passenger vehicles to undergo 

periodic testing for 

malfunctioning emission control systems. 

1985

EPA establishes 


stringent emission


standards for diesel-


powered trucks and


buses to take effect between 1991 and 1994. 


1990

Congress amends the Clean Air Act to require passenger vehicles to meet further reductions in hydrocarbons, carbon monoxide, nitrogen oxides, and particulate matter emissions. Areas with severe ozone problems are required to use reformulated gasoline. 

1991

EPA sets more stringent hydrocarbon and nitrogen 

oxide tailpipe standards for passenger vehicles. These 

standards, known as the Tier 1 standards, take effect 

beginning with 1994 models. U.S. blood-lead levels 

decrease 78 percent compared to 1978. 

1993

EPA requires the sulfur content of highway diesel fuel 

be reduced from 2,000 parts per million (ppm) to 500 

ppm. 

1994

Manufacturers of nonroad engines, including construction, agricultural, airport, and industrial equipment, are 

required to reduce emissions for the first time. 

1996

The Clean Air Act’s ban on


leaded gasoline officially


takes effect.


Office of Transportation and Air Quality — Progress Report 31 
1997

EPA establishes standards for nitrogen oxides, 

hydrocarbon, carbon monoxide, particulate matter, 

and smoke for new and re-manufactured dieselpowered locomotives and locomotive engines. 

EPA finalizes the National 

Low Emission Vehicle 

program, which achieves 

substantial air pollution 

reductions while providing the auto industry 

flexibility to meet new 

requirements in the most 

efficient manner. 

1998

OTAQ requires further emission reductions from new 

nonroad diesel engines. 

1999

OTAQ finalizes Tier 2 regulations for passenger cars, 

SUVs, and light-duty trucks, lowering gasoline sulfur 

levels by 90 percent. 

OTAQ requires new large marine diesel engines (e.g., 

fishing, tug, and tow boats) to reduce nitrogen oxides 

and particulate matter emissions. Similar standards 

are applied to recreational marine engines in 2002. 

2000

OTAQ’s Clean Diesel Trucks and Buses Rule requires 

90 percent emission reductions from engines and 

cuts sulfur levels in highway diesel fuel by 97 percent 

(to 15 ppm). 

OTAQ launches the Voluntary Diesel Retrofit Program 

to encourage fleet owners to install pollution-reducing 

devices and use cleaner-burning fuel in current fleet 

of diesel vehicles. 

2001

OTAQ’s Best Workplaces for CommutersSM


program is launched, formally recognizing


employers who provide outstanding com­


muter benefits to their employees. 


2002

The first restrictions on gasoline toxics take effect.


Traffic congestion costs U.S. travelers a combined 


3.5 billion hours of delay. 

2003

OTAQ establishes the


Clean School Bus USA


Program to reduce chil­


dren’s exposure to diesel


exhaust by encouraging


idling reduction and


cleaner school buses.


The first hydrogen fuel cell vehicle receives OTAQ’s 

approval for mass production. 

Approximately 135 million passenger cars are driving 

on 2.6 million miles of paved roads in the United 

States. 

2004

EPA’s landmark Clean Air Nonroad Diesel Rule takes 

effect, requiring 90 percent reductions in emissions 

from nonroad diesel equipment and reducing sulfur 

levels in nonroad diesel fuel by 99 percent. 

2005

OTAQ launches the National Clean Diesel Campaign 

to reduce emissions from existing and future 

diesel engines. 

32 Office of Transportation and Air Quality — Progress Report 

Office of Transportation and Air Quality (6401A) 

EPA420-R-05-011 

November 2005 

www.epa.gov/otaq 

Recycled/Recyclable—Printed with vegetable oil based inks on 100% postconsumer, process chlorine free recycled paper.