After stopping at the required distance from a railroad crossing, what should the driver do before looking and listening for a train?

AAMVA CDL Manual Section 10.4.3, p. 10-9; 49 CFR Part 380, Appendix D, Unit D1.6 (Railroad-Highway Grade Crossings)

Noise from the radio, the engine straining against the brake, or talking passengers can mask the sound of an approaching train, especially around a curve or in poor visibility. Securing the bus properly and quieting the cabin lets the driver actually hear what they're listening for.