In the early to mid 1990s, Air Districts throughout the state were concerned about the emissions from the large number of portable equipment. Most District rules did not exempt portable equipment from permit, however the traditional permitting structure was difficult for industry to comply with (e.g. obtaining permits for specific locations prior to operation, obtaining permits and paying fees in multiple different Districts).

As an alternative to traditional stationary source permitting, the California Air Pollution Control Officers Association (CAPCOA) developed a model portable equipment registration rule which any District could adopt to establish a registration program. The Yolo-Solano AQMD was one of the districts which adopted a local rule (Rule 3.3) on June 22, 1994.  However, because the requirements in this rule are dated (don't correlate with the ATCM), the District is considering repealing this rule.  For more information, contact Susan McLaughlin at 530-757-3667 or check our rule development page.

Based on legislation that was authored in the mid-1990s, the California Air Resources Board (ARB) promulgated a statewide Portable Equipment Registration Program (PERP) on March 27, 1997.  The regulation has been subsequently revised several times, including on June 22, 2006, December 7, 2006, and March 22, 2007.  These latest amendments (info brochure) were approved by the Officer of Administrative Law and therefore became effective on April 27, 2007.

The PERP program is optional for businesses, but if a business obtains a valid PERP and operates in compliance with the requirements, state law prohibits the District from also requiring local permits. The District is the agency primarily responsible for enforcing the PERP.

If you are planning on purchasing portable equipment or considering bringing portable equipment into our District, we encourage operators to contact David Smith at (530) 757-3662.

Update (June 14, 2007): For engines which are not EPA certified (also known as Tier 0 engines), if the units were not permitted or registered by 2006, they can no longer get into the PERP program and therefore any operation in the Yolo-Solano District is in violation of our rules and regulations.  The latest amendments to the PERP regulation and the ATCM gave some flexibility for Districts to permit or register Tier 0 engines for a limited period of time.  The Yolo-Solano AQMD has worked with our neighboring Districts to develop a regional Tier 0 policy, which our board approved on May 9, 2007.  The policy can allow for limited term usage of resident Tier 0 engines if a company enters a compliance agreement to settle the violation of not having a required permit.  If a company comes to the District voluntarily, the penalty amount will be less than for any engine which we find operating in violation.  For more information or to enter a compliance agreement, please contact Paul Hensleigh at (530) 757-3665.