CDL Hazardous Materials (H) Endorsement Test
Bulk packaging and tanks: practice questions
Our CDL Hazmat bank has 13 questions on this topic. Here are 4 of them with answers; the full mock exam draws from every topic, like the real one.
Question 1
Before moving a cargo tank, what must be closed?
- Only the main dome cover, if the tank is under half full
- All manholes and valves, however small the amount or short the distance
- Only valves on full tanks
- Nothing, if the tank is under half full
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B. All manholes and valves, however small the amount or short the distance — 49 CFR 177.834(j): you may not drive a cargo tank with hazmat unless all manholes are closed and secured and valves closed and free of leaks (CDL Manual 9.5.2)
Question 2
How is a portable tank different from a cargo tank?
- It is always smaller than 119 gallons, so it isn't bulk
- It never needs placards
- It is welded to the frame
- It is loaded and unloaded while off the vehicle
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D. It is loaded and unloaded while off the vehicle — Portable tanks are not permanently attached; the product is loaded or unloaded while off the vehicle (CDL Manual 9.5)
Question 3
When filling a cargo tank through an open filling hole, when do you ground the tank?
- After filling is finished, just before closing the hole
- Only if it is raining
- Only for gases
- Before opening the hole, keeping it grounded until the hole is closed
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D. Before opening the hole, keeping it grounded until the hole is closed — Ground the tank before opening the filling hole and maintain the ground until after closing the filling hole (CDL Manual 9.5.3)
Question 4
When should the liquid discharge valves on a compressed gas tank be open?
- Only when loading and unloading
- Whenever the tank is full
- While driving at highway speed
- When parked overnight
Show the answer
A. Only when loading and unloading — Keep liquid discharge valves on a compressed gas tank closed except when loading and unloading (CDL Manual 9.5.4)