Heavy Vehicle Road Rules and Safe Driving
The rules that change with size
Heavy vehicles obey the same road rules as cars, but several rules tighten because of mass, length and blind spots. Keep left unless overtaking applies on roads over 80 km/h and on multi-lane roads, and heavy vehicles must not travel in the right lane of a multi-lane road where a lower speed or lane restriction applies. Follow the signed speed limits for heavy vehicles, which are often lower than the general limit, and obey road train and B-double route signs. At level crossings, long vehicles must not enter unless there is room to clear the crossing completely. Use low gear and steady braking on long descents.
Safe driving concepts
Understand stopping distance as reaction distance plus braking distance, both rising sharply with mass. A loaded truck needs far more room than an empty one. Know your blind spots, especially the No-Zone down the left side and directly behind. When turning, swing wide but check for vehicles and cyclists on the inside. Load restraint and weight distribution affect steering and braking, so an uneven load is a safety issue, not just a compliance one.
Traps and rule of thumb
Questions often test following distance and lane use. A common trap is assuming the general speed limit always applies; heavy vehicle limits may be lower. Another is forgetting that a long vehicle must not block a crossing. Rule of thumb: at least a three-second gap in good conditions, doubled in rain, and never enter a crossing unless your whole vehicle fits. Worked example: a 25 m road train needs roughly 25 m of clear space beyond the crossing before it starts to cross.