1 subway train. In real tests done in NYC, the mean dbA for subway platforms was 81.1 vs. 76.0 for buses (which, by definition, run on the roads) https://www.

1 subway train. In real tests done in NYC, the mean dbA for subway platforms was 81.1 vs. 76.0 for buses (which, by definition, run on the roads) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2707461/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2707461/