Large Spark-Ignition (LSI) Engine Fleet Requirements Regulation Guidance Documents and Advisories

This page last reviewed September 6, 2017

All documents are provided in Adobe Acrobat (PDF) unless otherwise indicated.

On July 21 2016, the Air Resources Board approved amendments to the LSI Fleet Regulation, which include reinstating the Limited Hours of Use provision, became effective. The changes to the regulation are reflected in the advisories, FAQs, userguides, and forms below.

LSI Fleet Requirements Regulation Overview

  • Overview: Basic explanation of the regulation timeline and requirements.
  • Resumen de la Regulación: Explicación básica de la línea de tiempo y requisitos de la regulación.

Implementation and Enforcement Advisories

  • Advisory 08-01: Delay in Enforcement of First LSI Compliance Date. Allow Purchase Orders into Fleet Average Calculation.
  • Advisory 08-02: Exclusion of Gasoline-Fueled Ground Support Equipment from the LSI Fleet Average Calculation.
  • Advisory 08-03: Exclude from the fleet average calculation fully controlled late model year LSI equipment fleets and LSI equipment with engines greater than three liters in displacement; Extend deadline for use of purchase orders in the fleet average calculations.
  • Advisory 441: Enforcement of the Off-Road Large Spark-Ignition (LSI) Fleet Requirements Regulation.

Free Training Seminars

Course 505: Large Spark-Ignition (LSI) Engine Fleet Requirements Regulation

Frequently Asked Questions

LSI DOORS User Guides

The User Guides for DOORS are currently being updated. Once updates on a specific user guide is completed, they will be posted here. Please check back regularly for the user guide you're searching for.


The forms below are to be used to either request updates to information in a fleet's DOORS account that is not available for the fleet owner to update directly, or to submit information to ARB to complete annual reporting requirements.

Request for a Change in DOORS Information