The cost of convenience; Air pollution and noise on freeway and arterial light rail station platforms in Los Angeles

Light rail transit (LRT) is an increasingly popular mode of public transportation, and LRT stations tend to be built within roadway rights-of-way to reduce costs and traffic conflicts. This study examined the exposure of passengers to air pollution (in the form of particle number count) and noise at two kinds of LRT stations, those within freeway or arterial medians. Seventeen platforms were visited on average seven times in the summer of 2012. At the freeway platforms, noise levels were four times louder and particle counts were 75% higher than those in the arterial medians. When comparing open platform locations with those under shade canopies, the particle count was higher in open air but noise levels were lower.