Georgia CDL Tanker Test flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Surge direction

Liquid moves opposite to the change in vehicle motion. Braking throws product forward against the front bulkhead; accelerating throws it rearward, reducing weight on the steer axle.

Slack load surge

A partially filled tank lets liquid run the full length of the shell, producing the strongest surge. A full tank or nearly empty tank moves far less product.

Baffle effect

Baffles and bulkheads divide the tank into compartments, shortening the distance liquid can travel and reducing the surge force transmitted to the vehicle.

Smooth start rule

Engage the clutch and add throttle gradually. A hard launch sends liquid rearward, lifts weight off the front axle, and can cause a steering loss.

Smooth stop rule

Apply the brake gently and hold steady pressure. A sudden hard stop sends the whole product forward and pushes the tractor, lengthening the stop.

Surge and stopping distance

Forward surge adds force after braking begins, so a loaded tank needs more distance to stop than a dry van at the same speed and weight.

Following distance for tanks

Increase the gap beyond what a dry van needs. Surge and longer stopping distance leave less margin to react when traffic slows ahead.

Partial load hazard

Half-full tanks are the most unstable because the liquid has room to accelerate. Keep compartments full or empty where the design allows.

Tank center of gravity

A loaded tank carries its weight high, raising the center of gravity above that of a dry van and lowering the speed at which rollover becomes possible.

Rollover threshold

The lateral acceleration at which the inside wheels lift. Tank vehicles have a lower threshold than dry vans because of the higher center of gravity.

Speed squared effect

Centrifugal force in a curve rises with the square of speed. Going from 30 to 40 mph nearly doubles the outward force on the tank.

Advisory speed rule

Enter every curve at or below the posted advisory speed, and slow further when the tank is partly loaded, the road is wet, or the curve is off-camber.

Braking before the curve

Slow to the safe speed on the straight approach, then hold steady throttle through the curve. Braking inside a curve shifts weight and liquid forward.

High-risk rollover locations

Freeway off-ramps, ramp curves, and quick lane changes cause most tank rollovers. Steer smoothly and avoid sharp corrections at speed.

Lean correction response

If the tank leans or the load shifts outward, ease off the throttle and steer gently. Jerking the wheel back can trigger an unrecoverable rollover.

Product density and stability

A dense product raises the loaded center of gravity and the outward surge force. The same tank is less stable hauling heavy liquid than light liquid.

Wet curve adjustment

On wet pavement, tire grip falls while surge force stays the same, so the safe curve speed drops. Slow more than you would in dry conditions.

Load centering

Keep product weight centered and low in the tank. Uneven compartment loading shifts the center of gravity sideways and increases rollover risk in turns.

Tank braking rule

Brake earlier and lighter than in a dry van. Steady pressure avoids wheel lock, and the longer gap covers the extra distance surge creates.

Locked wheel danger

A locked wheel on a tank vehicle loses steering and quickly leads to a jackknife or spin. Release pressure to let the wheel roll again.

Drive-wheel skid recovery

Release the brake or throttle to restore rolling, then steer in the direction you want the front of the vehicle to go until grip returns.

Trailer skid recovery

Release the brakes so the tank wheels roll and regain grip, then steer to straighten the combination. Do not keep braking into the skid.

Front-wheel skid recovery

Ease off the throttle and steer gently toward the intended path. Hard steering during a front skid deepens the loss of control.

Jackknife prevention

Brake progressively and keep wheels rolling. Sudden full brake pressure on slick pavement locks the drives and folds the combination.

Leak emergency positioning

Stop away from ignition sources, shut off the engine, set the parking brake, and keep people upwind and uphill of the spill.

Spill reporting duty

Report any hazardous material release immediately. Do not try to stop a large leak without protective equipment and the training to do it.

Tank shell inspection

Check the shell, seams, baffles, and bulkheads for cracks, dents, corrosion, and leaks. Any structural defect means the tank must not be loaded.

Vent inspection

Confirm vents and manhole gaskets are open and intact. A clogged vent can collapse the tank under vacuum or rupture it under pressure.

Emergency valve check

Test the internal self-closing stop valve and the discharge emergency shutoff. Each must close fully and automatically when the handle is released.

Cargo tank specification plate

The specification plate identifies the tank design, such as DOT 406, 407, or 412. The plate must match the product being hauled and its placards.

Grounding and bonding check

Inspect ground and bond cables for continuity before transferring flammable product. A broken strap means no static path and no transfer.

Post-loading walkaround

After loading, walk the full vehicle to confirm hatches are dogged, valves closed, and nothing drips before the vehicle moves.