John O. Olawepo and L.-W. Antony Chen (both Environmental and Occupational Health) recently published an article on the "Health Benefits from Upgrading Public Buses for Cleaner Air: A Case Study of Clark County, Nevada and the United States." As the Regional Transportation Commission of Southern Nevada (RTC) has been transitioning from diesel to compressed natural gas (CNG) transit buses since 1999, this study assesses its health benefits using the U.S. Environmental Protection Agency's (EPA) Co-Benefits Risk Assessment (COBRA) model. Olawepo is a graduate student.