Cargo securement, loading and weight distribution
Cargo securement, loading and weight distribution
This domain tests whether you can load a heavy vehicle so it stays within its axle limits, keeps a low centre of gravity, and stays attached when the driver brakes, turns or hits a bump.
Loading principles
- Load forward against the headboard and keep the centre of gravity as low and as central as possible.
- Distribute weight so no axle or axle group is overloaded, then check with a weighbridge when the load is dense.
- Heavy items go low and over the drive axles, not high on the trailer deck.
- Nothing may project beyond the legal overhang without marking and, where required, a permit.
Securement
- Lashings must have an aggregate working load limit at least equal to the load, acting in each direction that the load could move.
- Use a minimum of two lashings on short items and at least four on long items, with edge protectors under chains or straps.
- Direct lashings (chains over the load) or tie-downs to rated anchor points; never to body panels, fuel tanks or brake lines.
- Re-check after the first 10–20 km and at every stop.
- Remove loose objects from the deck, close and latch the tailgate, and cover friable loads with a tarpaulin.
- No passengers in the cargo area. Dangerous goods need segregation, placards and documentation; livestock need penning and ventilation.
Worked example
A 10 t steel coil sits on a flat trailer with four chains rated 2.5 t working load each. Reasoning: four chains give 10 t aggregate, exactly the load weight, with no margin and no protection against forward movement if one chain slackens. The better answer is a coil cradle plus six rated lashings and edge protection, because the coil can roll and the aggregate must exceed the load with a margin.
Traps
- Counting lashings instead of adding their working load limits.
- Loading heavy freight at the rear, unloading the steer axle and destabilising the combination.
- Forgetting the re-check after the first few kilometres.