After loading hazardous material into a cargo tank, what must be verified before departure?
Correct answer: A. – The manhole closures are secured, and the liquid-discharge valves and closures are closed and leak-free
Federal regulation bars driving a cargo tank containing hazardous material unless every manhole closure is closed and secured and the liquid-discharge valves and closures are closed and leak-free. A limited exception applies to certain MC 338 tanks carrying only cryogenic-liquid residue. North Dakota’s CDL manual presents the same pre-departure rule.
Source: North Dakota Commercial Driver License Manual (2025–2027) — § 9.5.2, “Tank Loading”, 49 CFR § 177.834(j) — General requirements

