The Tank Vehicles endorsement test

The load pushes back

A tank that is not full contains a liquid free to move, and when the vehicle slows the liquid does not. That single fact generates most of this test.

Nine subjects, the longest list of any endorsement

49 CFR 383.119 sets them. The causes, prevention and effects of cargo surge. Braking a tank empty, full and partly full. Baffled and compartmented tanks against non-baffled ones. Tank type and construction. Cargo surge for liquids of varying density. Road grade and curvature with filled and empty tanks. Proper use of emergency systems. DOT specification tanks, their retest requirements and markings. Operating practices and procedures.

Count how many are surge

Causes and effects. Braking at three fill levels. Baffled against unbaffled. Liquids of different density. Grade and curvature. Five of the nine subjects describe the same physical problem from a different starting point, which is unusual in these regulations and is the clearest signal in the list about what the test is really asking.

Partly full is the dangerous one

A full tank has little room for the liquid to move and an empty one has nothing to move. A tank part loaded has both room and weight, so it is the case the questions keep returning to. Outage, the space deliberately left for expansion, is why a tank is often carried part full on purpose.

The one subject that is paperwork

DOT specification tanks, retest and marking. It is the only item on the list that does not concern how the vehicle drives, and it is easy to leave out of studying for exactly that reason.

Passing it

Three choices a question, 80% to pass. Our forms run twenty questions, which is our own length; New York publishes no count for this test.