APENs and air permits

 
Any business in Colorado that emits air pollution may be required to report its emissions and/or apply for a permit. Submitting an Air Pollutant Emissions Notice (APEN) is required to report your emissions, apply for a permit, or modify a permit.
 
Your APEN will be rejected if it is filled out incorrectly, is missing information, or lacks payment for the filing fee. The re-submittal will require a new filing fee. See our Application Rejection Frequently Asked Questions page for more information.
 
  • Introduction to APENs video.
  • Detailed guidance for calculating your emissions.
  • APEN/permit threshold table.
  • Ozone non-attainment area boundaries.
  • Common APEN and air permit exemptions.
  • APEN update guidance.

 

Oil & gas industry APENs and air permits  

Permits
Find forms to apply or modify (including APENs), and permitting process guidance.
 
Oil & gas APENs
If you just need an APEN and are not applying for a permit.
 
Administrative changes
Cancel, change ownership or company name, provide notice of startup, alternate operating scenario, relocation notice, or self-certify.
 
Resources

 

APENs and air permits for non-oil & gas industries
 
Permits
Find APENs and resources to apply for, modify or renew a permit.
 
Administrative changes
Cancel, change ownership or company name, provide notice of startup, alternate operating scenario, relocation notice, or self-certify.
 
Resources