Rail commuters experience dramatically improved air quality on board trains and at stations following rail line electrification, a study has found.
Researchers from the University of California, Berkeley, analysed the air quality aboard the San Francisco Bay Area’s Caltrain commuter rail line, which was recently electrified. They installed black carbon detectors at a number of stations and carried air-quality detectors aboard the trains.
For four weeks, they tracked the rapid improvements in air quality as old diesel locomotives were replaced by new electric trains.
In total, the team measured an 89% drop in carcinogenic black carbon exposure on the trains themselves and a significant reduction within and around the station monitored.
Caltrain operates the busiest commuter rail system in the western US, carrying millions of passengers a year along its 47-mile route between San Francisco and San Jose. Over the course of six weeks in August and September 2024, the system retired all 29 of...