CDL Tanker cheat sheet

Tank vehicle definition: an individual tank rated over 119 gallons and aggregate rated capacity of 1,000 gallons or more, permanently or temporarily attached.

CDL tanker endorsement (N) is required for such vehicles, including when the tank is empty.

Hazardous materials endorsement (H) is separate; the X endorsement combines tanker (N) and hazmat (H).

Smooth bore tanks have no baffles, so liquid surges freely from end to end.

Baffled tanks have internal walls with holes; baffles slow but do not stop liquid movement.

Bulkheads are solid walls that divide a tank into separate compartments and block flow between compartments.

Outage is the empty space left in a tank for expansion; tanks are not filled to the brim.

High center of gravity and moving liquid increase rollover risk compared with general freight vehicles.

Tank vehicles may carry liquid or gaseous materials; cargo tanks, portable tanks, and multiple tanks can qualify.

Inspect the tank shell for leaks, cracks, dents, corrosion, contamination, and secure mounting to the chassis.

Hoses: check for cuts, bulges, soft spots, leaks, worn couplings, and secure connections.

Valves: verify internal, emergency, and shutoff valves are undamaged, operate freely, and are positioned correctly.

Hatches, dome covers, gaskets, vents, and pressure-relief devices must be intact and closed or set for travel.

Piping, pumps, fittings, and discharge outlets must be free of leaks and loose connections.

Placards must match the cargo and be clean, legible, and properly displayed.

Grounding and bonding cables and clamps must be present and undamaged when required for flammable liquids.

Check tires, brakes, suspension, lights, and fire extinguisher as part of the pre-trip inspection.

After loading, recheck outage, closures, placards, and leaks before moving.

Liquid surge is load movement during acceleration, braking, or turning; it shifts weight and can push the vehicle.

Smooth bore tanks produce stronger surge than baffled or compartmented tanks.

Baffles reduce but do not eliminate surge; compartmented tanks confine liquid to separate sections.

A partially filled tank can be less stable because liquid has more room to move.

Sudden braking sends liquid forward, adding force and lengthening stopping distance.

Sudden acceleration sends liquid rearward; it can affect steering and traction.

Take curves slowly and at steady speed; high center of gravity raises rollover risk.

Increase following distance because surge can reduce control and stopping ability.

Empty or lightly loaded tank vehicles are more affected by wind and need lower speed.

Brake early and smoothly; abrupt braking causes liquid surge and loss of control.

Controlled braking: apply firm, steady pressure without locking wheels; release if wheels lock.

In a rear-wheel skid, release the brakes and steer in the direction the rear is sliding.

ABS prevents wheel lock but does not shorten stopping distance; safe speed and gap remain necessary.

On long downgrades, use a lower gear and engine braking; continuous heavy braking can cause fade.

In an emergency, hold the wheel firmly and use smooth steering; sudden maneuvers risk rollover.

Reduce speed on wet roads; hydroplaning makes steering and braking ineffective.

Liquid surge can push a stopped vehicle forward; keep firm brake pressure and control.

Emergency maneuvers should avoid sharp turns; tank rollover can occur at lower speeds than expected.

Bond the vehicle to the storage tank and ground to earth before loading flammable liquids; this prevents static sparks.

Before loading, set parking brake, chock wheels, shut off engine if required, and verify valves and hatches are set.

Never fill a tank to the brim; leave outage for expansion, especially with gasoline.

After loading, close and secure hatches, valves, and caps; recheck outage, placards, and leaks.

During unloading, stay with the vehicle, monitor hoses and valves, and know the emergency shutoff location.

Hazmat loads require shipping papers, placards, and emergency response information accessible in the cab.

Vapor recovery systems capture displaced vapors; connect hoses correctly and check for leaks.

Do not top off a tank; overfilling can cause overflow as liquid warms and expands.

If a leak or spill occurs, stop transfer, close valves, contain if safe, and report before restarting.