The current version of Rule 1110.2 applies to facilities with engines greater than 50 rated brake horsepower; however, Rule 1110.2 also contains emission limits and other requirements applicable to linear generators. Unlike internal combustion engines (ICEs), linear generators produce electricity by driving magnets through copper coils in a linear motion and the thermochemical reaction takes place at lower temperatures than ICEs, which results in lower emissions without the need for add-on air pollution control devices. In order to have a rule with dedicated requirements specific to the technology and capabilities of linear generators, Proposed Rule 1110.3 (PR 1110.3) has been developed with updated emission limits and new provisions which incorporate existing requirements for linear generators from Rule 1110.2 into PR 1110.3. Specifically, PR 1110.3: 1) establishes the rule’s applicability to include all linear generators fueled solely by natural gas; 2) defines linear generator and other terms to provide context and clarity; 3) establishes concentration-based emission limits for nitrogen oxides (NOx), volatile organic compounds (VOC), and carbon monoxide (CO); and 4) establishes requirements for conducting maintenance, source testing, monitoring, reporting, and recordkeeping. PR 1110.3 also includes limited exemptions for: 1) laboratory units used for testing and research purposes; and 2) emergency standby units, units used for fire-fighting and flood control, or any other emergency unit approved by the Executive Officer which have permit conditions that limit operation(s) to 200 hours or less per year as determined by an operational non-resettable totalizing time meter. With requirements for linear generators established in PR 1110.3 in lieu of Rule 1110.2, Proposed Amended Rule 1110.2 (PAR 1110.2) contains changes that would: 1) remove all requirements applicable to linear generators; 2) provide clarifications to the definition of an engine; and 3) define linear generator for the purpose of exempting this technology from Rule 1110.2. By providing separate and distinct requirements for linear generators and engines in PR 1110.3 and PAR 1110.2, respectively, stakeholders will benefit from having improved clarity when implementing the applicable requirements.