Section 111 of the Clean Air Act authorizes the EPA to develop technology based standards which apply to specific categories of stationary sources. These standards are referred to as New Source Performance Standards (NSPS) and are found in 40 CFR Part 60. The NSPS apply to new, modified and reconstructed affected facilities in specific source categories such as manufacturers of glass, cement, rubber tires and wool fiberglass. As of 2013, there are approximately 90 NSPS.

The NSPS are developed and implemented by EPA and are delegated to the states. However, even when delegated to the states, EPA retains authority to implement and enforce the NSPS.

Compliance Monitoring

Sources subject to NSPS are required to perform an initial performance test to demonstrate compliance. To demonstrate continuous compliance, some NSPS require sources to utilize continuous emission monitors. Sources may also be required to monitor control device operating parameters to demonstrate continuous compliance. Consistent with EPA’s Clean Air Act Stationary Source Compliance Monitoring Strategy, NSPS sources that meet the Clean Air Act definition of “major source” generally receive a full compliance evaluation by the state at least once every two years.

In general, EPA measures NSPS compliance by requiring affected facilities to conduct initial performance tests.  Initial performance tests are followed by required continuous monitoring of operating parameters and/or direct monitoring of the regulated emissions.

Also, the National Stack Testing Guidance focuses on those issues associated with the conduct of stack tests and the interpretation of the test results.

State Implementation Plans

Section 110 of the Clean Air Act requires states to submit to EPA State Implementation Plans (SIPs) which provide for the implementation, attainment, maintenance and enforcement of the National Ambient Air Quality Standards.

States have the primary role for enforcing SIPs. However, upon approval by EPA, SIPs become enforceable as federal law. Federal requirements for SIPs can be found in 40 CFR Part 51.

EPA monitors compliance of SIPs via review of state-issued air permits.  EPA review ensures that the permits are written in accordance with applicable SIP provisions.  EPA may bring enforcement actions against affected sources that violate the provisions of or fail to obtain an air permit.