EVEN AS THE U.S. EXPLORES THE COMPLEX CHALLENGES OF global warming, air pollution remains widespread and dangerous. Millions of Americans live in areas that have recognized air pollution problems. Grave health effects—including death—are all too common. And the threat is not just to people: dirty air sickens and kills plants and animals and creates ugly haze that obscures spectacular views.

Five policy changes could make the air we breathe cleaner and healthier. The American Lung Association and other public health and environmental organizations recommend these steps as the core of a clean air agenda for the nation:

1 Clean up coal-fired power plants. Coal plants are one of the largest contributors to atmospheric particulate matter and ozone—which are linked to worsened asthma and increased rates of heart attacks and premature death—as well as greenhouse gases and toxic substances, including mercury. We need to immediately reduce these emissions once and for all.

2 Strengthen ozone air standards> voluntarily. In March 2008 the Environmental Protection Agency issued new national air quality standards limiting ozone smog. Unfortunately, the standards allow far more ozone than the agency’s own science advisers unanimously recommended and far more than Clean Air Act requirements would allow. President George W. Bush overturned recommendations for stronger protections. The American Lung Association, along with several states and public health and environmental groups, challenged those decisions in court. But now the EPA could voluntarily remand its 2008 decision and issue new standards that truly protect people and ecosystems.

3 Clean up oceangoing vessels. Cruise ships, container ships and tankers emit staggering amounts of smog-forming nitrous oxides, sulfur dioxide, heat-trapping carbon dioxide and particulates, among them black carbon (soot). New evidence shows that pollution from these vessels reaches surprisingly far inland. The U.S. government has requested that the International Maritime Organization (IMO) create an “emissions-control area” in American waters, including off Alaska and Hawaii. Although the U.S. signed the International Convention for the Prevention of Pollution from Ships, it cannot enforce those requirements until the IMO grants the right to create the control areas along its coastlines.

4 Improve the pollution-monitoring network. Numerous sensors regularly collect data about air quality that can be sent to an EPA database to determine if the air in a community meets national standards. Yet the instruments are installed only in about 1,000 of the nation’s 3,141 counties, and budget cuts have forced states to reduce the number of sensors or staff who maintain them and analyze the data. Emerging science indicates that some areas with no monitoring face serious health risks, particularly poor neighborhoods adjacent to highways or dirty industries. The EPA should work with scientists and state officials to lower monitoring costs and expand the ability to track pollutants.

5 Enforce the law. Since 1970 the Clean Air Act has driven the nation’s ability to curb air pollution. But rules have eroded as political decisions have taken the place of scientific ones and as delay after delay in enforcing specific requirements have mounted until only costly lawsuits prompt action. By restoring a commitment to science and law, the nation can make great strides.

The full list of needed steps is more detailed (see www.lungusa.org/cleanairstandards). But these five actions will go a long way toward breaking the pattern of weakening clean air safeguards by ignoring science and delaying actions. America must continue to reduce air pollution; the health and lives of people and ecosystems depend on it.