Current ozone standards are stringent enough to protect Americans' health.

Joel Schwartz submitted comments to EPA on the agency’s proposal to lower the 24-hour PM2.5 standard from 65 mg/u3 to 35 mg/u3.

On November 29, the U.S. Supreme Court will hear oral argument in Massachusetts v. Environmental Protection Agency (EPA). In this much-watched case—part of a broader campaign for the regulation of carbon dioxide—several states and environmental organizations have argued that the EPA must regulate CO2 under the Clean Air Act.

Samuel Thernstrom testifies at a congressional hearing on the EPA's response to air quality issues in the aftermath of September 11, 2001.

Al Armendariz, the top Environmental Protection Agency official in the oil-rich Southwest region, resigned from his post, effective Monday. It’s the latest twist in the never-ending and increasingly ugly fracking fracas. A two-year old video had surfaced last week (and since pulled) featuring Armendariz comparing his “philosophy of enforcement” to...

The controversy over the Clean Air Act is worth understanding because it reveals a pivotal development that EPA and the environmental groups would prefer to conceal: the 40-year-old act is no longer a sensible way to regulate large-volume conventional air pollutants such as ozone and particulate matter.

The Environmental Protection Agency’s reasons for not using its usual approach to regulating greenhouse gases unwittingly shows that it is obsolete for controlling conventional pollutants. Congress should update the Clean Air Act.