CDL Tanker Practice Test

• No, a tank attached temporarily counts exactly as one attached permanently
• Yes, a portable tank rides as freight, so only cargo securement rules apply
• Yes, a temporary mounting is exempt as long as the tank is emptied before it comes off
• Yes, unless the liquid in it is a hazardous material

The endorsement covers tanks attached to the vehicle or the chassis either permanently or temporarily, so a tank strapped on for a single trip is caught in exactly the same way as one plumbed in. What decides the question is the rated capacity of the tanks and the class of vehicle, never how long they are staying on it, which is why hiring a tank rather than owning one changes nothing.

• A tank endorsement, because the liquid does not have to be a hazardous material
• Nothing extra, because the tank endorsement only covers hazardous liquids
• Nothing extra, because a food product tank counts as a sanitary vehicle
• A hazardous materials endorsement, because any liquid carried in bulk is treated as hazardous

The endorsement follows the tank and its rated capacity, not what is inside it. Drinking water in tanks of that size on a Class B vehicle needs the endorsement exactly as diesel would, which surprises drivers who take the word "tanker" to mean fuel or chemicals. Hazmat is a separate endorsement answering a separate question and is not triggered by the tank itself.

• A tank endorsement, because a Class C vehicle needs one when the tanked load is a hazardous material in liquid or gas form
• Nothing beyond the Class C licence, because the tank endorsement only reaches Class A and Class B vehicles
• Nothing beyond the Class C licence, because a vehicle that small cannot reach the rated capacity figures
• A tank endorsement only if those tanks are permanently plumbed into the chassis

Class C works the opposite way round from the bigger classes. On a vehicle needing a Class A or B CDL the endorsement turns on rated capacity alone and the contents are beside the point; on a Class C vehicle it is required when the load is a hazardous material in liquid or gas form in tanks of that capacity. So for Class C the contents are what bring the endorsement in, and that asymmetry is the part drivers get wrong.

• Any sign of leaking, under and around the vehicle
• The tread depth on the trailer tires
• The reading on the air pressure gauge
• The play in the fifth wheel locking jaws

Tank vehicles vary enormously, but on every one of them leaks come first. The check is for signs of leaking under and around the whole vehicle, not just at the valves, because a wet patch on the ground is often the only warning of a cracked shell or a failed joint. The other three are real checks, they are simply not the one this section singles out.

• Carrying liquid in a leaking tank is a crime, and the driver can be cited, stopped from driving further and left liable for the clean-up
• It is allowed as far as the next terminal, so long as the leak goes on the inspection report on arrival
• It is allowed if the liquid is not a hazardous material
• It is a defect for the next scheduled maintenance, so the trip may be completed

Hauling liquid or gas in a leaking tank is not a paperwork problem, it is an offence. The driver is cited, prevented from driving any further, and can be held liable for cleaning up whatever has escaped. Nothing about the load being ordinary rather than hazardous changes that, which is the part drivers most often get wrong.

• Making sure each item actually works
• Checking each item is present, since testing it is the loading rack's job
• Checking it only when the load is a hazardous material
• Nothing before a trip, because it is covered by the annual inspection

Special purpose equipment is checked for function, not just for presence. A shut-off system that does not shut off and a grounding cable with a broken clamp both pass a walk-past and fail the moment they are needed. The same goes for the emergency equipment the vehicle is required to carry: find out what is required, then confirm you have it and that it works.

• Every one of them is closed, because a tank vehicle is never driven with an open valve or manhole cover
• A manhole cover may stay open until the vehicle reaches the road, to let the load settle
• One valve should be left open so the liquid has somewhere to expand
• The discharge valve may be left open if the tank is baffled

Never drive a tank vehicle with open valves or manhole covers, whatever the reason offered. Room for the liquid to expand is made by leaving outage in the tank when it is loaded, not by leaving something open on a moving vehicle, and an open manhole with a surging load underneath it is simply a spill waiting for the first hard stop.

• Before loading, before unloading and before moving the vehicle
• Before loading only, since unloading is the receiver's responsibility
• At the end of the day, as part of the post-trip inspection
• Only when the tank is carrying a hazardous material

All three occasions count, because each one can go wrong differently: a wrongly set valve spills product at the rack, strands the load at the delivery, or lets liquid move where it should not while the vehicle is driving. Treating it as a loading-only check is the common shortcut.