In April 2007, the City and County of San Francisco adopted an Ordinance requiring public projects to reduce emissions at construction sites starting in 2009. In March 2015, the City expanded the existing Ordinance to require public projects to further reduce emissions at construction sites in certain areas with high levels of background concentrations of air pollutants.

The City and County of San Francisco has long been a leader in protecting residents' public health. In a dense, urban center like San Francisco, construction sites can be located in areas of the City with high levels of background concentrations of air pollutants in the Air Pollutant Exposure Zone. In addition, these locations may be located close to sensitive users, such as children and the elderly, who are more susceptible to the negative effects of air pollutants such as diesel particulate matter. According to the California Air Resources Board, off-road equipment such as construction equipment is the sixth largest source of diesel particulate matter emissions in California and can cause a public health risk and nuisance to sensitive populations.

Through the implementation of the requirements of the Clean Construction Ordinance, contractors for publicly-funded construction projects can substantially reduce their emissions and the associated public health risk at construction sites.

The Planning Department developed the following guidance and templates to assist city agencies in meeting their responsibilities under the Clean Construction Ordinance: