Explain the nature and enforcement of the national ambient air quality standards (NAAQS)

What will be an ideal response?

The Clean Air Act directs the Environmental Protection Agency (EPA) to establish national ambient air quality standards (NAAQS) for certain pollutants. These standards are set at two different levels: primary, which is to protect human beings, and secondary, which is to protect vegetation, matter, climate, visibility, and economic values. Specific standards have been established for carbon monoxide, nitrogen oxide, sulfur oxide, ozone, lead, and particulate matter.
Although the Environmental Protection Agency (EPA) establishes air quality standards, the states are responsible for their enforcement. The federal government has the right to enforce these air pollution standards if the states fail to do so. Each state is required to prepare a state implementation plan (SIP) that specifies the state plans to meet the federal standards. The EPA has divided each state into air quality control regions (AQCRs).