HTV Driving Theory cheat sheet

Octagonal signs mean stop; inverted-triangle signs mean give way; circular signs are regulatory; diamond or triangular yellow/black signs warn of hazards.

A red circle with a diagonal slash prohibits an action; a blue circle imposes a mandatory instruction; a red circle without a slash restricts an action.

A solid centre line on your side prohibits crossing to overtake; a broken centre line permits crossing only when the road ahead is clear and safe.

At a stop sign or stop line, make a complete stop, give way to traffic and pedestrians, and proceed only when the way is clear.

At a roundabout, give way to traffic already circulating; enter only when safe and signal your intended exit.

At an uncontrolled intersection, apply the priority rule of the local traffic system; where give-way-to-right applies, yield to vehicles approaching from your right.

When an emergency vehicle approaches with lights or siren, clear its path as local law requires and do not block an intersection.

Height, width, weight and bridge-limit signs are legal limits; a route is unsuitable if the vehicle or combination exceeds any posted limit.

Pre-trip sequence: check documents and permits, walk around the vehicle, inspect under the bonnet and in the cab, test brakes and air systems, then confirm the load and coupling.

Tyres must meet the legal tread minimum, be inflated to the specified cold pressure, and be free of cuts, bulges, exposed cords and serious uneven wear.

Check wheel nuts and indicators for looseness or movement, inspect rims for cracks, and look for oil, coolant, fuel or air leaks.

Test all required lights, reflectors, indicators, brake lights, marker lamps and warning devices; replace failed lamps before departure.

Build air pressure from the minimum to governor cut-out and compare the time with the manufacturer's or inspection standard; investigate slow build-up.

Perform the specified air-leak test with the engine off and brakes applied; a pressure loss greater than the allowed limit is a defect.

Conduct a low-speed brake test in a safe area; the vehicle must stop squarely without pulling, unusual noise or abnormal pedal or brake-chamber behaviour.

A major defect affecting safe operation, such as a brake, steering, tyre or coupling fault, means the vehicle must not be driven until repaired and signed off.

A defect report records vehicle identity, date, defect location, description, severity, reporter and action taken; keep it available for inspection.

Lateral acceleration in a turn is approximately v squared divided by radius; reduce speed before the curve because tyre grip and rollover margin are limited.

Rollover threshold falls as centre-of-gravity height rises and track width narrows; high loads, fast cornering, sudden steering and crosswinds increase risk.

Off-tracking is the difference between front-wheel and rear-wheel paths in a turn; it increases with wheelbase and articulation, so allow extra swept width.

Check height, width, length, axle mass and gross mass against route limits before departure; a low bridge or weak pavement can make a legal load route illegal.

Use mirrors and a guide when reversing; if visibility or clearance is uncertain, stop and check rather than continue on assumption.

ABS modulates brake pressure to prevent wheel lock and helps preserve steering during hard braking, but it does not guarantee a shorter stop on every surface.

A retarder or engine brake assists speed control on descents but does not replace service brakes; select a low gear before the descent and avoid brake overheating.

Crosswinds, passing high-sided vehicles and sudden load shifts reduce stability; reduce speed and increase steering smoothness when these hazards are present.

Use at least a three-second following gap in good dry conditions; increase it for heavy vehicles, rain, darkness, poor visibility or a heavy load.

Reaction distance equals speed in metres per second multiplied by reaction time; convert km/h to m/s by dividing by 3.6.

Braking distance increases with the square of speed; doubling speed can roughly quadruple the braking distance under otherwise similar conditions.

Scan about 12 to 15 seconds ahead, and check mirrors, instruments and blind spots regularly so hazards are detected before they become emergencies.

The posted speed limit is a maximum, not a target; choose a lower speed when road, weather, visibility, load or traffic conditions require it.

Maintain a space cushion and identify an escape route before traffic closes up; avoid being boxed in beside heavy vehicles or barriers.

Do not linger in another vehicle's blind spot; if you cannot see the driver's mirrors, assume the driver cannot see you.

At night or in rain, reduce speed, increase following distance and use low beam when facing traffic or following closely.

Hazard perception follows identify, predict, decide and execute; act early because a heavy vehicle needs more time and distance to change speed or direction.

Gross vehicle mass is the maximum total vehicle mass including payload, fuel, driver and fluids; gross combination mass applies to the tractor and trailer together.

Payload equals gross vehicle mass minus tare mass; the calculated payload must also satisfy every axle and axle-group limit.

Place heavy items low, centred and over or near the load-bearing axles; a high or offset centre of gravity increases rollover and handling risk.

The load must not obscure required lights, reflectors, plates, mirrors or the driver's view, and must not make the vehicle unstable or exceed dimension limits.

Use rated restraints and tie-downs; a common minimum is an aggregate working load limit at least 50 percent of the cargo mass, but the local standard governs.

Use direct restraint, headboards, chocks or containment where required; check straps, chains, binders, tensioners and anchor points for wear and correct attachment.

Recheck load security shortly after departure and at required intervals, because settlement, vibration and strap stretch can loosen a load.

Projecting loads may require flags, lights, signs or permits; confirm the local overhang and oversize rules before moving.

Distribute weight so no axle is overloaded even if the total mass is legal; axle overloads damage tyres, brakes, suspension and pavement.

The compressor builds air pressure; the governor cuts out at the system's maximum and cuts in at its minimum, and these values are manufacturer-specific.

A low-pressure warning must activate before pressure falls below the safe operating level; further loss can apply spring brakes automatically.

Spring brakes are held off by air pressure and applied by strong springs; a major air loss therefore produces a parking or emergency brake application.

Drain air tanks at required intervals to remove water and oil that can freeze, corrode or contaminate valves and brake components.

Perform the specified static leak test and build-up time test; excessive pressure loss or slow build-up is a defect requiring repair.

Brake fade occurs when foundation brakes overheat; use a low gear and controlled braking on descents instead of riding the brakes continuously.

An engine brake or retarder is an auxiliary system, not a service brake; disable it when slippery-surface rules require to avoid drive-wheel lockup.

ABS may cycle during hard braking; maintain firm pedal pressure and steer as needed rather than pumping the brake pedal.

Check slack adjusters and pushrod stroke against the limit; a stroke beyond specification indicates poor adjustment or a fault and must be repaired.

Fatigue impairs judgment, reaction time and vigilance; do not begin or continue duty when unfit from lack of sleep, illness, alcohol, drugs or medication.

Many heavy-vehicle fatigue schemes require a break from driving after a set period, commonly 5.5 hours; confirm the exact rule applying to your licence and operation.

Daily and weekly driving, work and rest limits vary by jurisdiction and scheme; plan the journey so no limit is exceeded.

Record duty, driving, rest and availability accurately and promptly; keep records for the required retention period.

Never falsify a record or ask another person to falsify one; record corrections transparently according to the required procedure.

Plan rest stops, fuel, loading and traffic delays before departure so the schedule does not pressure the driver to exceed limits.

A fit-for-duty check includes sleep, illness, medication effects, alcohol and drugs; report unfitness under company and legal procedures.

Emergency or exemption provisions are limited, must be lawful and must be documented; they do not permit falsifying ordinary duty records.

Time-zone changes and long waiting periods can affect fatigue management; record times consistently and use actual rest opportunities rather than assumed rest.

At an incident, stop safely, switch on hazard lights, set warning devices and keep yourself and others out of traffic before assisting.

Call emergency services with location, direction of travel, number of vehicles, injuries, hazards and access restrictions; follow the operator's instructions.

Do not move an injured person unless there is immediate danger such as fire, traffic or a hazardous spill.

Control severe bleeding with firm direct pressure and clean dressings; do not remove an embedded object from a wound.

For adult CPR, give 30 chest compressions at about 100 to 120 per minute followed by 2 rescue breaths if trained; use an AED as soon as available.

For a vehicle fire, evacuate, call emergency services and attack only a small fire with the correct extinguisher using the PASS technique if trained.

For a breakdown, move as far off the carriageway as possible, use hazard lights and warning devices, and keep occupants in a safer area away from traffic.

If air pressure is lost, stop safely, use gears or retarder to control speed and expect spring brakes to apply; do not continue driving.

For a fuel, chemical or cargo spill, keep ignition sources away, contain the spill only if safe, warn others and report the hazard to emergency services.