NV CDL General Knowledge key terms

The total ground covered from the moment a hazard is seen until the vehicle comes to a complete halt, made up of perception distance, reaction distance, and braking distance added together.

The distance a vehicle travels while the driver's eyes see a hazard and the brain recognizes it as something requiring action, typically about one second of travel at highway speed.

The ground covered between recognizing a hazard and actually pressing the brake pedal, roughly three-quarters of a second for an alert driver, and longer when tired or distracted.

The distance needed to stop once the brakes are applied, which grows with the square of speed and is stretched further by wet, icy, or gravelly pavement and by worn tires or brakes.

The sum of perception distance, reaction distance, and braking distance; at 55 mph a loaded rig can need more than the length of a football field to stop on dry pavement.

The empty road area kept around the vehicle on all sides so there is room to steer or brake out of trouble when another driver makes a mistake or traffic suddenly slows.

The gap maintained behind the vehicle ahead, measured in seconds by counting from when that vehicle passes a fixed object until your front bumper reaches it.

A minimum following gap of one second for each ten feet of vehicle length at speeds under 40 mph, so a 60-foot combination needs at least six seconds.

A pre-planned path out of a developing problem, such as an open shoulder or adjacent lane, identified by scanning ahead so a driver is never trapped with only one option.

The skill of scanning far ahead and to the sides to spot trouble early, including brake lights, merging traffic, road work, and pedestrians, before it becomes an emergency.

Any activity that pulls eyes, hands, or mind away from the road, such as texting, eating, adjusting a radio, or reading a map, sharply raising crash risk in a heavy vehicle.

The drowsiness and slowed reaction that build during long hours behind the wheel; it impairs judgment much like alcohol and must be countered with rest, not caffeine or open windows.

A systematic check of tires, brakes, lights, fluids, couplings, and cargo done before each trip to catch defects that could cause a breakdown or crash on the road.

A three-part check of leaks, low-air warning, and emergency spring brakes performed before driving; static leak tests confirm the system holds pressure with the engine off and brakes released.

The engine-driven pump that builds and maintains air pressure in the brake system, governed to cut out around 120 to 125 psi and cut back in when pressure falls.

A buzzer and light that must activate before pressure drops below 60 psi, warning the driver that braking power is failing and a stop must be made immediately.

A parking and emergency brake held off by air pressure; when pressure is lost the spring applies the brake automatically, which is why a rig cannot be moved without adequate air.

The loss of stopping power when brakes overheat from repeated or prolonged use, common on long downgrades; it is avoided by gearing down and using engine braking instead of riding the pedal.

A retarder or compression-release device that uses engine resistance to slow the vehicle on downgrades, saving the service brakes from overheating and fading.

A downhill technique of applying the brakes firmly for a few seconds to cut speed several mph, then releasing, repeated as needed so brakes cool between applications.

The remaining rubber depth in the tire grooves; front steer tires need at least 4/32 inch and all other tires at least 2/32 inch, checked with a gauge during inspection.

A sudden loss of tire pressure; the driver should hold the wheel firmly, avoid hard braking, ease off the accelerator, and steer to a safe stop off the roadway.

Loss of tire traction that sends the vehicle sliding; recovery means releasing the brakes or accelerator, steering in the direction of the skid, and avoiding overcorrection.

Riding on a film of water so tires lose contact with the pavement; it happens at higher speeds on wet roads and is countered by slowing down and avoiding sudden steering or braking.

The tendency of the rear wheels of a long vehicle to cut inside the path of the front wheels during a turn, so the driver must swing wide and watch the trailer in the mirrors.

Moving to the left before a right turn so the trailer's rear wheels clear the curb, done only after checking that no vehicle is alongside in the passing lane.

The hazard of a car slipping into the space on the right as a truck swings left for a turn; the trucker must check mirrors and may need to block the lane before turning.

Shifting technique for non-synchronized transmissions: press the clutch, shift to neutral, release the clutch, match engine speed, press the clutch again, and engage the next gear.

Shifting without using the clutch by matching engine and road speed so the gears slide in smoothly; it requires skill and is not recommended for inexperienced drivers.

The layout of gear positions on the shift knob, which the driver must memorize so eyes stay on the road and shifts are made at the right engine speed.

Revolutions per minute of the engine; watching the tachometer helps the driver shift at the right point and avoid lugging or over-revving the engine.

Running the engine at too low an rpm in too high a gear, which strains the engine and drivetrain; it is avoided by downshifting before the engine labors.

The use of tiedowns, straps, chains, and blocking to keep a load from shifting, spilling, or falling off; tiedowns must meet working load limits and be inspected during the trip.

A strap, chain, rope, or web used to anchor cargo to the vehicle, with a working load limit and a required number based on cargo length and weight.

Movement of cargo during transit that can change steering and braking behavior; it is prevented by proper securement and checked at each stop during the trip.

Exceeding the vehicle's gross, axle, or tire weight ratings, which reduces braking and handling performance and is both unsafe and a violation of weight laws.

The area beside and behind the truck that cannot be seen in the mirrors; drivers must check mirrors often and signal early because large vehicles have very large blind spots.

Scanning both side mirrors and the rearview regularly, especially before lane changes, turns, and stops, to track traffic and keep the trailer aligned in its lane.

Using turn signals and brake lights to tell other drivers what you intend to do, given well in advance because large vehicles maneuver slowly and need extra room.

A quick tap of the brakes to test stopping ability and to warn following traffic that you are slowing, especially before a downgrade or in heavy traffic.