New report highlights California's hidden air quality menace

provided by Environmental Defense

nvironmental Defense last month released Smaller, Closer, Dirtier: Diesel Backup Generators in California, a study which for the first time quantifies the threat to air quality and human health posed by diesel backup generators (BUGs), which are commonly used by businesses and institutions during blackouts and other times of power shortage. During last year's power outages many of these older, diesel-fired generators, which number more than 11,000 throughout the state and lack even basic pollution controls, generated significant air pollution in major California cities.

    The study presents evidence showing that both the number of BUGs and their usage hours increased dramatically throughout the state during last year's power crisis. The study also highlights how the health risks from BUGs are exacerbated by their tendency to be clustered in the state's most populous areas. BUGs are also found more often in poorer neighborhoods and communities of color, and many are located near schools, where they are a contributing source to California's soaring juvenile asthma rate. More than 150,000 children in California are at increased risk of exposure to hazardous diesel engine emissions as a result of the existence of BUGs near their schools. Diesel exhaust presents 70% of cancer risk of air toxins within the United States, and as many as 60,000 people nationwide die each year because of fine particulate emissions, which BUGs emit at an extremely high rate.

    “Backup generators are California's hidden air quality menace,” said Nancy Ryan, deputy regional director of Environmental Defense's California office. “They are in our schools and our offices, our hospitals and our banks. But the good news is that this is an air-quality problem that we know how to solve – we just need to set stringent health-based standards and free up the funds to implement them.”

    Smaller, Closer, Dirtier examines four air quality districts in detail: Los Angeles, San Diego, Sacramento, and Fresno, and presents some analysis of San Francisco as well. The report is currently available at Also available online are an atlas showing the location of BUGs in major California cities and a BUG mapper showing the locations of BUGs near a user-supplied address.

    “Unfortunately, in the recent Sacramento budget battles, California may cut the funding that would finance enforcement and speed the retrofit and replacement of these dirty engines. This funding should be included in the final budget, for the health of our citizens and the quality of our air,” Ryan said.

    Environmental Defense, a leading national nonprofit organization based in New York, represents more than 300,000 members. Since 1967 they have linked science, economics, and law to create innovative, equitable, and cost-effective solutions to the most urgent environmental problems.