California Code, Health and Safety Code - HSC § 44299.90

(a) Diesel emissions from schoolbuses contribute to significant health and safety risk to children, cause air pollution, and contribute to greenhouse gas emissions.

(b) The intent of this chapter is to ensure funds made available by the Highway Safety, Traffic Reduction, Air Quality, and Port Security Bond Act of 2006 are equitably distributed among geographic regions to retrofit and replace older and higher polluting schoolbuses in furtherance of improving air quality and protecting public health.