Emergency Systems and Tank Regulations Flashcards

A DOT-specification cargo tank must have an external visual inspection and leakage test at least how often?

Answer: Every year

Under 49 CFR 180.407, DOT-specification cargo tanks need an external visual inspection and leakage test at least once each year. The longer 5-year interval applies to pressure retests, not to these checks.

A cargo tank is marked with a test date next to the letter "K". Which test does this code stand for?

Answer: Leakage test

The "K" test marking identifies the leakage test. The other letter codes identify other inspections, such as V for external visual and P for pressure.

On the test markings of a DOT-specification cargo tank, what does the letter "P" indicate?

Answer: Pressure test

"P" marks the pressure test. The markings record which test was done and when.

You are loading a tank that is only partly full. Which condition makes liquid surge most likely?

Answer: A smooth bore tank partly filled with liquid

A partly filled smooth bore tank has nothing to slow the liquid, so it can surge forward and back. Bulkheads and full tanks limit that movement.

What is the main reason to leave outage (empty space) when filling a tank with a liquid that expands when warmed?

Answer: To allow room for the liquid to expand without overfilling or leaking

Liquids expand as they warm, so the outage gives the product room to grow. Without it, the tank could overflow or be stressed.

Product begins leaking from a hose connection while you are unloading a cargo tank. What should you do first?

Answer: Activate the emergency shutoff or stop the flow of product

Stopping the flow, using the emergency shutoff if needed, limits the amount released. Driving away or waiting makes the spill worse.

When can a driver leave a cargo tank unattended during loading or unloading of a regulated product?

Answer: Never, a qualified person must stay attending and watch the tank

Federal rules require a qualified person to attend the cargo tank during loading and unloading, staying within a short distance with a clear view of it. The attendant must be able to act fast.

Before opening the dome of a tank that carries a flammable liquid for loading, what should you do about static electricity?

Answer: Bond the tank to the fill pipe or grounded system before opening

Bonding the tank to the fill system equalizes the electrical charge so no spark jumps across the opening. Do this before opening the dome.

What should you do when driving a partly filled tank vehicle that will need to stop?

Answer: Apply the brakes early and gently, allowing for liquid surge

Surge can push the truck as the liquid moves, so braking early and gently keeps control. Hard braking makes the surge worse.

Why is a tank vehicle more likely to roll over on a curve than a flatbed carrying the same weight?

Answer: The liquid load raises the center of gravity and can shift in the curve

A tank has a high center of gravity, and liquid shifting to the outside of a curve adds to rollover risk. Reducing speed before the curve is the best protection.