Load Security Beyond the Seal
A sealed trailer can still contain an unstable load. A seal helps reveal unauthorised opening; it does not prevent pallets sliding, cartons collapsing or individual items moving during transport.
Mixed loads make load security particularly demanding. Different heights, weights and packaging strengths mean one securing arrangement may leave some goods exposed while placing excessive pressure on others.
For transport managers and dispatch teams, the practical task is to coordinate strapping, buckles, edge protection, lashing, gap control. Each component needs a defined role within the complete securing system.
What does load security mean for mixed loads?
Load security means keeping cargo stable and restrained against the forces encountered during transport, while enabling safe unloading. Start with a load plan covering cargo weight, dimensions, centre of gravity, packaging strength, vehicle suitability and delivery order.
For road transport in Great Britain, DVSA guidance specifies restraint against forces equivalent to the load’s full weight forwards and half its weight sidewards and rearwards. These are system requirements, rather than a shortcut for choosing strap quantities.
Therefore, assess each cargo group and the overall arrangement. Dense crates, soft cartons and tall pallets can present different sliding, tipping and crushing risks.
Strapping and lashing - two different jobs
Strapping commonly binds products together or secures them to a pallet, creating a unit that can be handled. Vehicle lashing restrains that unit within the transport space.
Both jobs matter. DVSA guidance says goods must be secured to the pallet before loading; securing the pallet alone does not restrain goods than can move on it.
Choosing equipment for the securing method
For web lashing, understand the label:
- Lashing capacity (LC) informs direct-lashing calculations
- Standard tension force (STF) informs frictional tie-down calculations
Breaking strength is not a substitute for these values. Strap angles, friction and attachment points also influence performance. Avoid selecting equipment solely by strap width or an advertised strength figure.
Source: DVSA
Buckles connect the strapping ends, making compatibility central to a reliable joint. Purchasing a strong strap and a unrelated buckle does not establish the performance of the assembled system.
Before ordering, request confirmation of:
- Suitable strap material, width and thickness
- The specified buckle design and finish
- Correct threading and tensioning instructions
- Tested joint or system performance
- Any restrictions on reuse
Also distinguish strapping buckles from roof-mounted buckle straps inside curtain siders. These serve different applications and should not be treated as interchangeable equipment.
A useful procurement specification names the strap, buckle and application method together. this also makes warehouse training and repeat ordering more consistent.
Edge protection has two related functions: spreading restraint pressure across vulnerable packaging and protecting straps where they contact sharp or abrasive surfaces.
DVSA recommends force-spreading arrangements, including edge protectors for fragile, crushable or non-uniform cargo. However, a cardboard corner board intended to support cartons should not be automatically be assumed suitable for protecting webbing against a metal edge.
Specify protection for the actual contact surface, strap width and applied force. Check that it remains correctly positioned after tensioning. Likewise, a strap spanning two tall pallets may pass above a shorter pallet between them. Adding corder protection will not solve that missing restraint; the lower load needs its own suitable arrangement.
Dunnage bags can act as blocking devices within suitable cargo transport units. Their selection depends on the cargo forces they must resist, including the potential for sliding or tipping.
Consequently, choose the bags using the gap dimensions, cargo characteristics, transport mode and manufacturer’s instructions. Confirm permitted inflation pressure and whether the surrounding cargo and boundaries can support the arrangement.
Inflation alone does not demonstrate adequate restraint. Nor should a bag force fragile cartons against a rigid neighbouring load.
For journeys involving road, rail or sea, consider the complete route. The CTU Code covers packing and securing across the intermodal chain.
A mixed-load example
Consider a shipment containing tall carton pallets, a low rigid crate and irregular boxed components. First, check that each unit is stable and appropriately packaged. Then plan its position around weight distribution, access and delivery sequence.
Assess restraint separately for each cargo group. Protect carton edges where pressure must be spread, and use suitable abrasion protection wherever webbing contacts sharp surfaces.
Finally, assess remaining gaps. Use appropriate blocking or dunnage where supported by the securing plan. This sequence avoids expecting one strap across several different heights to perform every task.
Check load security throughout the journey
Use a short, repeatable inspection process:
Confirm cargo weights, dimensions and loading instructions.
Inspect pallets, restraints, buckles and attachment points.
Check strap routing, tension and edge protector placement.
Verify gap control and the security of individual units.
Record the arrangement and communicate unloading instructions.
Effective load security starts with understanding how each item could move and how each restraint controls that movement.
Before your next mixed shipment, review the cargo, packaging, vehicle and delivery sequence together. Share those details with our load securing specialist to establish suitable products for your needs.