Air permitting for standby generator sets can vary wildly from site to site and when misunderstood can have a major impact on project success. Although EPA regulations have stabilized and are thought to be well understood, ever-increasing local requirements are changing the criticality of air permitting for engine-driven generator sets. In this session we will provide a brief overview of regulated emissions constituents and will describe common permitting requirements, strategies employed to meet these requirements and common pitfalls related to emissions permitting.