zero-emission school bus
(8) Zero-emission school bus The term “zero-emission school bus” means a school bus that is certified by the Administrator to have a drivetrain that produces, under any possible operational mode or condition, zero exhaust emission of— (A) any air pollutant that is listed pursuant to section 7408(a) of this title (or any precursor to such an air pollutant); and (B) any greenhouse gas.