The build quality of outdoor traffic routes should be similar to the standards for public highways.
When you plan a traffic route, your risk assessment should include answers to these questions:
The law that requires traffic routes to be wide enough for traffic to circulate freely only applies to routes laid out from 1 January 1993. On traffic routes that existed before then, where it is not practical to widen the road, you should introduce, where necessary:
Straight routes used by road-going vehicles should usually be at least 3.5 m wide in each direction, although where speeds are slow, traffic is light, and very wide vehicles or overhanging loads are unlikely, this may be reduced to 3 m.
Routes need to be wide enough to allow for modern materials handling equipment, such as pedestrian-operated pallet handlers and stackers. You might have to decide on traffic routes around the workplace before you use this equipment regularly.
If possible, entrances and gateways should be wide enough to allow two vehicles to pass each other safely.
Routes should also be wide enough to allow vehicles to pass oncoming or parked vehicles safely without leaving the route.
You need to measure and record the vertical clearance under overhead obstructions on all routes.
Your measurement should include any suspended lighting, ventilation or other service features, which are often added after the initial design.
You can then use this information to decide how much overhead space vehicles will need to move around and work safely.
Road vehicles in the UK are usually less than 4.5 m tall. However, tipper vehicles in the raised position can be much taller than this and need more clearance, see Tipping.
If possible, routes used by road vehicles should allow for 5.1 m clearance (which is the normal height of UK motorway bridges). However, if there is a steep ramp running down to an overhead obstruction (for example, when entering a building), the effective height could be reduced for longer vehicles. See how this happens [PDF 28KB].
Clearance for goods vehicles may change with raising or lowering the mid-lift axle, if this is a vehicle feature.
A change to the level of the driving surface could also affect clearance. If a route is resurfaced, you may need to take measurements again.
If an accident could result in dangerous mixing of loads, or a load mixing with substances stored or piped on-site, try to find a different and safe route to transport the substance.
It is better to restrict vehicles at a place where the driver can choose another route. They should not have to reverse or manoeuvre in a tight space when they find out that they cannot go ahead. Width and height restriction posts can be effective for this.