Under the federal Clean Air Act, the Environmental Protection Agency (EPA) establishes health-based air quality standards that all states must achieve. The California Clean Air Act also establishes requirements for cities and counties to meet.  South Coast AQMD was created by the state legislature to facilitate compliance with the federal Clean Air Act and to implement the state air quality program.  Toward that end, South Coast AQMD develops regulations designed to achieve these public health standards by reducing emissions from business and industry.

At South Coast AQMD, a regulation is composed of rules, each of which deals with a specific topic within that regulation.  For example, Regulation II deals with permits, while Rules 201 through 221 pertain to specific types of permits, how they are granted and administered, and their impact.

South Coast AQMD staff develops rules based on control measures identified in the Air Quality Management Plan and which are designed to reduce air pollution from specific sources.  Generally, the rule-making process incorporates extensive information gathering and research into available technologies, coordination with industry groups, and analysis of the economic impact of each proposed rule or rule amendment.  South Coast AQMD provides an opportunity for public input on every proposed rule.  At public workshops and consultations, the public can voice suggestions and concerns about the impact of a proposed rule.  A final public hearing is held before the South Coast AQMD Governing Board before the Board votes on the proposed or amended rule.

In addition to developing air pollution regulations, South Coast AQMD is under a legal obligation to enforce these regulations. Air pollution regulations are primarily meant to ensure that the surrounding (or ambient) air meets federal and state air quality standards. AQMD also has broad authority to regulate toxic and hazardous air emissions, and these regulations are enforced in the same manner as those which pertain to the ambient air quality standards.  South Coast AQMD has devised a broad compliance program to provide for enforcement activities.