Before accelerating and merging back into traffic from a stop, what must a bus driver correctly judge, per the manual?

49 CFR 383.117(a)(6), operating practices and procedures not otherwise specified; AAMVA CDL Manual Section 4.3.3 (p.4-3)

Misjudging a merge gap while pulling out from a stop is a direct contributor to the intersection and pull-out crashes the manual describes. The core safety rule is simple but critical: never assume other drivers will brake to let you in.