- Skip Navigation

Note: This message is displayed if (1) your browser is not standards-compliant or (2) you have you disabled CSS. Read our Policies for more information.

  • Business & Agriculture
  • Residents
  • Government
  • Education
  • Taxes & Finance
  • Visiting & Playing
  • Family & Health

Indiana Department of Environmental Management

Air Quality in Indiana

Air Quality in Indiana > Permits > Air Permit Applications > Interim Approval Information Interim Approval Information

An Interim Approval allows the applicant, under certain limited circumstances and at their own risk, to commence construction of a new emissions unit at an existing source or modification of an emissions unit at an existing source while the permit application is being reviewed. Interim approvals are subject to the requirements of 326 IAC 2-13-1.

Detailed information preparing an Interim Petition, and the applicable forms, are provided below. For additional information, please also refer to Frequently Asked Questions & Answers about Interim Approvals.


The interim petition is applicable to proposed modification/revision to an existing source operating under valid operating permit(s) and located in an attainment area.

Non-eligible Projects

Modifications/revisions ineligible for the interim petition program include:

  • Construction of a new major PSD facility or major PSD modification to an existing source, or
  • Construction in a nonattainment areas that would emit those pollutants for which the nonattainment designation is based, or
  • Construction of a totally new plant, or
  • Any modification that is subject to 326 IAC 2-4.1 (New Source Toxics Control).


Questions or Concerns

If you have questions, the OAQ Permit Reviewer of the Day can provide more information about the air permitting program. Contact the Permit Reviewer of the Day by calling (800) 451-6027 ext. 3-0178, or dial (317) 233-0178.