Which act primarily governs air quality regulations in the United States?

The Clean Air Act is the primary federal law in the United States that governs air quality regulations. Enacted in 1963 and significantly amended in 1970, 1977, and 1990, this act establishes national standards for air quality to protect public health and the environment from harmful air pollutants. It mandates the Environmental Protection Agency (EPA) to set and enforce these standards, allowing for the regulation of emissions from both stationary sources, such as factories, and mobile sources, such as vehicles.

The act aims not only to control air pollution but also to promote state implementation plans, which allow states to create their own programs that meet or exceed federal requirements. This flexibility encourages local solutions to air quality issues while ensuring that national standards are maintained.

In contrast, the Clean Water Act regulates discharges of pollutants into the waters of the United States and quality standards for surface waters. The Resource Conservation and Recovery Act focuses on waste management and the disposal of hazardous waste. The Air Quality Control Act, while it seems relevant, is actually an earlier version of the Clean Air Act and does not encompass the current comprehensive framework established for air quality management.