CDL · Inspecting Tank Vehicles

Before transporting a load in a tanker, what should the driver verify about the tank's valves and connections?

Correct answer

That all valves are in the correct position (closed for transport), connections are secure and not leaking, caps and plugs are in place, and there are no drips or signs of leakage

  1. A Nothing needs checking
  2. B Only the top vent
  3. C Only that they are painted
  4. D That all valves are in the correct position (closed for transport), connections are secure and not leaking, caps and plugs are in place, and there are no drips or signs of leakage

Why this is the answer

Tanker valve and connection inspection: Before transport, verify: ALL VALVES in the correct position (closed for transport — an open valve could leak product or open during transit); CONNECTIONS secure and tight (loose connections leak); CAPS AND PLUGS in place on outlets/discharge points; NO LEAKS — check for drips, wet spots, residue, or odor around valves, connections, the discharge, and the tank shell; HOSES (if carried) secured and in good condition; for hazmat — proper securing of valves and protective housing.

Why: A leaking valve or connection wastes product, creates a hazard (slippery road, fire risk for flammables, environmental damage), and may violate regulations; an open valve could discharge product while driving.

Leak check: Walk around the entire tank looking for any sign of leakage before and during the trip; ALSO inspect: tank shell, mounting, manhole covers, vents, safety/emergency equipment; the tank is the cargo container so its integrity — including all valves and connections — is critical; a tanker with leaking valves or connections must not be driven until repaired; this is a key tanker pre-trip item.

Source: FMCSA CDL Manual — Tanker Valves and Connections

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About this topic: Inspecting Tank Vehicles

The combination-vehicle inspection adds fifth wheel, kingpin, glad hands, and trailer-specific items to the standard pre-trip routine. This is one of 14 Tanker questions on inspecting tank vehicles, each with a full explanation on a single study page.

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