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Area Designations for 1997 Fine Particle (PM2.5) Standards

Fine Particle Designations

Information provided for informational purposes only Note: EPA no longer updates this information, but it may be useful for historical purposes. See the PM Designations Home Page for more recent information about PM Designations.

Fine particle pollution represents one of the most significant barriers to clean air facing our nation today.

These tiny particles — smaller than 2.5 micrometers in diameter — have been scientifically linked to serious health problems such as aggravated asthma, chronic bronchitis, and shortness of breath. Batteries of scientific studies have linked respiratory-related hospital admissions, work and school absences and even premature death to levels of fine particles in the air.

We are letting people know about the quality of the air they are breathing by “designating” areas of the country as “attainment” or “nonattainment” with the national ambient air quality standards for fine particles.

This action on fine particles compliments our April 2004 action to designate areas for the 8-hour ozone standard.

What is the “designation” process for the national fine particle standards?

Under the Clean Air Act when EPA revises an air quality standard (as we did for particulate matter in 1997), the Agency must officially “designate” areas of the country as meeting or not meeting the standards. Under the law, those areas that violate the standards, or are nearby and contribute to a violation, are “nonattainment.” All other areas are “attainment.”

Governors and Tribal leaders submitted their recommendations for nonattainment areas in June 2004. EPA provided notice of potential changes to the state and tribal recommendations in June 2004. We have been working with the states to understand the technical issues involved with making these designation decisions.

What does a “nonattainment” designation mean for your area?

The Clean Air Act lays out several basic requirements for all nonattainment areas. Early next year EPA plans to propose a PM2.5 implementation rule to determine how to interpret these requirements for PM2.5 nonattainment areas.

These basic requirements include:

Air quality plans – For each nonattainment area, a state must develop a plan to show how the area will meet the standard as expeditiously as practicable. If the area cannot attain the standard within five years (considering the severity of pollution and time needed for installation of controls), the area can qualify for an extension of one to five years.

New Source Review – The state plan must include a preconstruction permitting program designed to ensure that air quality is not significantly degraded from the addition of new and modified factories, industrial boilers and power plants.

Transportation conformity – In nonattainment areas, transportation projects that are federally funded must result in emissions consistent with those allowed in the area’s air quality plan, so that they do not worsen air quality or interfere with meeting air quality standards. This “conformity” requirement is a way to ensure that federal funding and approval are given to those transportation activities that are consistent with air quality goals.

Reasonable controls – The law also requires that state plans for nonattainment areas require reasonably available control technology, reasonably available control measures, and reasonable further progress along the way to meeting the standard. The PM2.5 implementation rule will propose specifically what these requirements mean for PM2.5 nonattainment areas.

What does “nonattainment” really mean to an area?

There is a widespread perception that a nonattainment designation will significantly limit growth; however, history shows that growth in many nonattainment areas (e.g. Dallas-Fort Worth, Atlanta) across the country has outpaced other cities in their regions.

There is a common misperception that nonattainment areas have their highway funds cut off or are otherwise under sanctions. Sanctions do NOT apply to any area unless a state fails to develop or implement a plan. Historically, that has occurred only very rarely.

What is EPA doing to help areas meet the fine particle standards?

EPA is taking actions to ensure that the federal government is doing its part to help local areas address the challenges of reducing emissions of fine particles. The Agency has issued and proposed environmental regulations that will reduce emissions from diesel trucks, diesel buses, cars, trucks, SUVs, off-road vehicles, and power plants. These rules, together with actions the Administration has proposed for further reducing emissions from power plants, will help bring the vast number of areas with fine particle problems into attainment with the national standards. Below are additional details on especially significant EPA rules:

The NOx SIP call went into place in most of the East during the summer of 2004. This rule will reduce summertime emissions of nitrogen oxides (NOx) by 900,000 tons when fully implemented. Emissions of nitrogen oxides can contribute to the formation of ground-level ozone and fine particles.

The Acid Rain Program requires a 50% reduction from 1980 levels of sulfur dioxide (SO2) emissions from power generation under a nationwide cap and trade program. Much of this reduction already has been achieved. The program also required annual NOx emissions to be cut by approximately 2.1 million tons starting in 2000.

Reductions from diesel vehicles and “non-road” engines will significantly cut emissions that impact levels of fine particles.

  • The Clean Diesel Truck and Bus Rule will put the cleanest running heavy-duty trucks and buses in history on America’s roads, building a fleet that will be 95 percent cleaner than today’s trucks and buses. On-highway compliance requirements take effect with the 2007 model year.
  • The Clean Air Non-road Diesel Rule will cut emission levels from construction, agricultural and industrial diesel-powered equipment by more than 90 percent. It will also remove 99 percent of the sulfur in diesel fuel by 2010, resulting in dramatic reductions in particles from all diesel engines. The rule also limits sulfur in nonroad diesel fuel to protect the vehicle’s control devices.
  • Clean School Bus USA is a program to reduce children’s exposure to diesel exhaust and the amount of air pollution created by diesel school buses. By retrofitting buses, the program will cut harmful emissions from these buses by 20 to 50 percent. Initially launched in April 2003, Clean School Bus USA brings together partners from business, education, transportation and public health organizations to eliminate unnecessary public school bus idling, to retrofit buses and to replace the oldest buses with new, less polluting buses.
  • The Voluntary Diesel Retrofit Program’s goal is to reduce the unhealthy diesel exhaust emissions of trucks that otherwise would be unaffected by EPA’s upcoming standards for new diesels. Fleet owners and operators have committed to retrofit more than 150,000 diesel-powered trucks, buses, and non-road equipment. As a result, more than 200,000 tons of pollution, including emissions of PM, NOx, carbon monoxide, and hydrocarbons will be prevented. Participants reduce emissions by retrofitting diesel engines with pollution controls, implementing anti-idling programs, and using clean-fuel alternatives, such as ultra-low sulfur diesel and compressed natural gas. EPA provides technical assistance and grant opportunities.
Tailpipe standards for cars, trucks, and SUVs are being phased in. These national rules will ensure that the mobile sector is doing its part to reduce emissions. Over the coming decade, these measures will cut smog and particle-causing pollution from new vehicles by 77 to 95 percent. The rule also limits sulfur in gasoline. When fully implemented, they will provide cleaner air for all Americans, each year preventing over 4,000 premature deaths, 260,000 asthma attacks among children, and 173,000 cases of childhood respiratory illness.

Along with the existing programs listed above, the President’s Clear Skies legislation (or in the alternative the proposed Clean Air Interstate Rule) – would bring many areas into attainment with the national standards for fine particles, and assist attainment in the rest. The proposed Clean Air Interstate Rule would require 29 eastern states and the District of Columbia to significantly reduce and permanently cap emissions of SO2 and/or NOx. In 2015, NOx emissions from the power sector would be 65% below today’s levels. SO2 emissions from that sector would be 50% below current levels by 2015 and approximately 70% below current levels when fully implemented. With these efforts, EPA is working to further reduce emissions from power plants through a cap and trade program.

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