The SCAQMD prepared the CEQA Air Quality Handbook in April 1993, and made minor revisions in November 1993. Copies of this handbook can be obtained by contacting AQMD's Subscription Services at 909-396-3720.

While the Handbook is under revision, it is recommended that the lead agency follow the calculation methodologies in Chapter 9 and the Appendix to Chapter 9 in the Handbook. Other methodologies can be used as long as documentation is provided regarding the source and applicability to the project. 

Lead agencies should also be aware that the on-road mobile source emission factors in Table A9-5-J1 through A9-5-L are obsolete. The most current on-road mobile source emission factors can be found at the California Air Resources Board (CARB) website at www.arb.ca.gov

The SCAQMD also recommends that the lead agency avoid using the screening tables in the Handbook’s Chapter 6 for the following reasons:

1. The tables were derived using an obsolete version of CARB's mobile source emission factors inventory (EMFAC7E) instead of the currently approved version (EMFAC2011), and

2. The trip generation characteristics of the land uses identified in the Chapter 6 screening tables were based on the fifth edition of the ITE Trip Generation Manual. The most current version of this manual is the sixth edition.

In conjunction with the Handbook, the SCAQMD developed the Mobile Assessment for Air Quality Impacts (MAAQI) to calculate emissions from land use projects. The SCAQMD recommends against using the MAAQI model for the same two reasons identified above. The SCAQMD recommends using other approved models for this purpose, such as the CalEEMod land use emissions model.