Load security, vehicle weights and route planning for lorry drivers

Car drivers rarely think about what they are carrying or where the road can take them. For a lorry driver both questions decide whether a journey is legal and safe. LGV theory questions in this area combine physics, vehicle limits and planning, so this guide covers all three.

Securing the load

The driver is legally responsible for the load once the lorry is on the road, even if someone else loaded it. If you are not happy with how it is secured, ask for it to be reassessed or reloaded before you leave.

How restraint works

A load wants to keep moving when the lorry brakes, turns or hits a bump. Friction alone is never enough: on a bump the load goes momentarily weightless and friction disappears. The usual design standard (BS EN 12195-1) expects a restraint system to resist a force equal to about 80% of the load’s weight forwards and 50% sideways and rearwards.

Restraint comes from:

• the vehicle structure: headboard, bulkheads, side boards, stanchions and coil wells
• blocking: loading tight against the headboard, with chocks or dunnage filling gaps
• lashings: webbing straps, chains or ropes attached to rated anchor points
• friction matting to work with the other methods

A standard curtain is a weather cover, not restraint, unless the vehicle body is specifically rated for it.

On the road

Check the load again after the first few miles and after each drop, because straps loosen as the load settles. Heavy items go low and in the centre, close to the headboard. Liquid in a partly filled tank surges under braking and pushes the vehicle forward: brake early and progressively, and corner gently.

If the load shifts, find a safe place to stop, assess it and get help. Do not try to reach a destination with an unstable load.

Weights and dimensions

A lorry has two kinds of weight limit:

You can be inside the gross limit and still overload an axle. DVSA calls one cause the diminishing load effect: after you drop part of the load at the rear, the remaining weight is carried further forward and can overload the front or drive axle. Plan the order of drops and re-position the load if needed.

The general limits in Great Britain include a maximum of 44 tonnes for a six-axle articulated lorry, a maximum width of 2.55 metres (2.60 metres for refrigerated bodies), and overall lengths of 16.5 metres for a standard articulated lorry and 18.75 metres for a drawbar combination. Your own vehicle’s limits are on its plating certificate and plate.

There is no legal height limit, which is why height is a planning issue. If your vehicle is over 3 metres high, its height must be shown in the cab, and the walkaround check includes making sure the marker is correct. The height changes when you raise the fifth wheel, swap trailers or load a different trailer, so update it.

A load that overhangs the rear must be clearly marked, and long overhangs need marker boards. Typical wrong answer: “an overhang does not matter if it is under the trailer length”.

Planning the route

Before setting off, check every restriction on the route against your vehicle’s height, width, length and weight:

• Low bridges. Signs show the clearance in feet and inches and usually metres. If you are not sure you will clear it, do not try. If you strike a railway bridge, call the number on the bridge identification plate, or 999 if there is a danger, so trains can be stopped.
• Weight restrictions. A sign with “7.5 t” means vehicles over that maximum gross weight may not enter, usually with an “except for loading” plate for deliveries on that road. Weak bridges may show their own lower limit.
• Width and length limits in villages and town centres.
• Lorry control schemes and permits. London, for example, has a night and weekend lorry control scheme and requires HGVs over 12 tonnes to hold a safety permit under its Direct Vision Standard.
• Clean air zones and low-emission zones that charge or restrict older vehicles.

A sat-nav built for cars does not know your dimensions. Use a lorry-specific system with your vehicle’s details set, and still read the signs.

Plan rest stops into the route too. Lorry parks fill early in the evening, and running out of hours with nowhere legal to stop is a planning failure, not an excuse. The limits that govern this are in drivers’ hours for lorry drivers.

DVSA’s code of practice on securing loads on HGVs and goods vehicles covers equipment and different load types in detail. For the checks that come before loading, read daily vehicle checks and heavy vehicle braking, see the container, part-load and high-load answers in HGV theory test questions explained, then try the loading and dimension questions in the LGV mock tests.