Maine Air Emissions Inventory Reporting System

MAIRIS is a free, web-based reporting system developed by the Maine Department of Environmental Protection (DEP) to assist Maine facilities with their annual air emissions reporting requirements. MAIRIS allows the DEP to efficiently package and submit the reported emissions data to EPA electronically.

User Registration and Electronic Signature Agreement

Every facility must have a responsible official registered as the Approver to submit the inventory. The Approver also designates those individuals who will help prepare the inventory as Editors. Facilities register these users by submitting the agreement below.

MAIRIS User Registration and Electronic Signature Agreement (pdf)

NOTE: This form must be completed before anyone can use and submit data through MAIRIS. Maine DEP must receive the signed agreement before adding, creating, or removing existing users. FAX and e-mail copies are not acceptable. Please mail the completed form to:

Stacy Knapp, MAIRIS Project Manager
Department of Environmental Protection
Bureau of Air Quality
17 State House Station
Augusta, ME 04333-0017

Here are some User Registration and Electronic Signature Agreement Frequently Asked Questions (pdf)

Use this form if the Approver is staying the same and only the Facility Editors need to be updated: MAIRIS User Registration for New Facility Editors Only (pdf)

Here is a reference manual that can be downloaded and printed: MAIRIS Facility Users' Manual (pdf)

If you have questions about your registration or account, contact Stacy Knapp 207-287-2235.

MAIRIS Training

Maine DEP has created several short training videos demonstrating the steps necessary to complete an annual emissions inventory using MAIRIS. The videos will cover the progression of steps for all required information.

Segment 1 - Welcome to MARIS A pre-recorded introduction to using the online Maine Air Emissions Inventory Reporting System, registering user accounts and logging into MAIRIS for the first time. (06:03)

Segment 2 - The MARIS menu and entering required facility data A pre-recorded overview of MAIRIS menus and what data to enter first. (07:02)

Segment 3 - Entering Information for a Unit A pre-recorded segment that will explain how to enter the required information for an emissions unit and its associated pollution controls, exhaust points, and processes. (10:04)

Segment 4 - How to Enter Estimated Emissions During this segment we explain how to enter the emissions produced by each of your facility’s emissions processes. (9:20)

Segment 5 - How to run a Completeness Report During this segment we explain how to enter the emissions produced by each of your facility's emissions processes. (5:15)

Segment 6 - How to Change the Status of, Certify, and Submit an Inventory During this segment we will explain how to change the status of, certify, and submit an emissions inventory. (7:20)

Segment 7 - What to do if an Inventory is Returned During this segment we will explain what to do if an inventory is returned. (3:02)

Maine DEP Default Emission Factors

Maine DEP has preloaded MAIRIS with a "default" set of emission factors for the required emissions for many processes. This includes default factors for most Hazardous Air Pollutants (HAPs) for the inventory years when they are required. Facilities may use the default factors or their own factors, with proper documentation. The spreadsheet linked below sources each of DEP's default emission factors for HAPs.

If you have any questions about the default factors, please contact Stacy Knapp 207-287-2235.

Default HAP Emission Factors (excel)

The MAIRIS Process

Below is a visual overview of the MAIRIS Process. View a larger version (pdf).


We are here to help

To ensure that your questions will be addressed as promptly as possible, please email us at or use the Help Request function in MAIRIS