Air quality permits, like building and other business permits, are a part of doing business in California. Yolo-Solano AQMD issues air quality permits to regulated businesses in Yolo County and northeastern Solano County.

Who Needs a Permit?

Permits are required by state and federal law for any operation or equipment that has the potential to emit air contaminants. Permits are required of both small and large businesses.

What Type of Permit Do Businesses Need?

The District issues and/or enforces the following types of permits:

Stationary Source Permits

A stationary source permit is required for any facility, process, machine or equipment that has the potential to directly emit air pollution. This includes commercial diesel engines, boilers, automotive paint booths, gas stations and a host of other sources.  Portable equipment (e.g. diesel engines powering electrical generators or compressors, sand blasters, grinders & chippers) must be permitted or registered.  Vehicles are regulated by the state Air Resources Board and generally does not require permits from the local Districts.

Title V Permits

Title V permits are required for large industrial facilities that trigger certain federal requirements.

Agricultural Operating Permits

Certain large stationary agricultural sources are required to apply for agricultural operating permits.

Confined Animal Facility Permits

Large confined animal facilities such as dairies are required to apply for special permits with the District.

Agricultural Engine Registrations

All ag engines (excluding mobile agricultural equipment like tractors, spray rigs, harvesters) greater than 50 horsepower must be registered with the District.

Portable Equipment Registrations

Portable equipment rated over 50 horsepower and certain other Particulate emitting equipment require local Stationary Source Permits, or in lieu of getting a permit with each of the 35 air districts it operates in, if it qualifies, it may be able to obtain statewide registration.

When Should Businesses Apply for Permits?

For new regulated businesses or new processes within existing regulated businesses, air quality permits are required before construction begins. The District also requires permit filings before a modification to a process or equipment is implemented and before permitted equipment is replaced or relocated. For ag engines and portable equipment, registrations are required before the equipment is brought onsite or used.

Permit filings are also required whenever a change of ownership occurs.

Why Are Air Quality Permits Required?

Permits are issued to ensure that all equipment and processes comply with federal, state, and District rules. These rules have been implemented to ensure that public health is protected from the harmful effects of air pollution.

Yolo-Solano AQMD does not meet all air quality health standards set forth by the U.S. Environmental Protection Agency or the California Air Resources Board. Because of that, the District is required to create and implement plans designed to improve air quality. Issuing permits allows the District to work with businesses to ensure that their operations comply with District air quality strategy.

The California Health and Safety Code (Chapter 4, Article 1, Section 42300) lays out the responsibilities to secure air quality permits: “Before any person builds, erects, alters, replaces, operates, or uses any article, machine, equipment, or other contrivance which may cause the issuance of air contaminants, such person must obtain a permit to do so from the air pollution control officer of the district.”

How Much Do Air Quality Permits Cost?

Yolo-Solano AQMD has some of the lowest permit costs in the region. The Master Fee Schedule is available, though exact costs of permits are often dependent on the details of a project. Our staff is available to help estimate permit costs in advance of a filing.

Where Can Permit Applications Be Found?

We have a full list of our air quality permit applications available on our Applications & Forms page. Please do not hesitate to call our Engineering Division (530-757-3650) with any questions before submitting an application.