Dock traffic lights are red and green signals mounted outside and inside a loading bay to tell the driver and dock staff when it is safe to move or load. Interlocks are control links that stop equipment operating out of sequence, for example preventing the door opening until the trailer is restrained, or the leveller operating until the door is fully open.
Where does this fit at a dock in Derbyshire?
If a site in Derbyshire has had door panels damaged by levellers raised too early, a leveller-to-door interlock is a straightforward fix to consider. Food and chilled operations around Derbyshire with inflatable shelters often add interlocks so the shelter only inflates once a trailer is docked and restrained.
Older docks in Derbyshire with separate door and leveller controls can be brought into a proper sequence by adding interlocks that stop equipment working out of order.
Our part of the job in Derbyshire is to survey, quote and manage; the fitting itself is done by specialist installation engineers working under our management. The survey and the written quote are free. Once the fixed price is accepted, we agree dates that work around your deliveries and shifts, including out-of-hours working where needed. Every installation is tested before handover, and you receive the documentation for each item fitted.
What does HSE guidance say about stopping drivers leaving too early?
HSE guidance (followed by HSENI in Northern Ireland) says there should be safeguards against drivers driving away from a loading bay too early, and it names traffic lights as one of the measures. Vehicle or trailer restraints, and the person in charge keeping keys or paperwork until it is safe, are the others listed in HSE's guide to workplace transport safety (HSG136) and its loading factsheet.
Traffic lights are a signal, not a physical barrier, so they work best as part of a clear procedure or alongside a restraint. Your risk assessment should decide the combination. In Northern Ireland the regulator is HSENI.
Interlocks also touch on door safety law. Under regulation 18 of the Workplace (Health, Safety and Welfare) Regulations 1992, or the Northern Ireland 1993 equivalent, powered doors need suitable and effective features to prevent them trapping anyone. Interlocks must never bypass those features, and door control work should respect BS EN 12453, the standard for safety in use of power-operated doors.
Read more in our guide to preventing drive-away and trailer creep.
How do inside and outside dock traffic lights work together?
Inside and outside dock lights always show opposite colours: when the driver sees red, dock staff see green, and the other way round. Each light is aimed at a different person, so each one only ever gives one instruction.
- Outside light, facing the driver: red means stay on the bay because loading is in progress; green means the bay is clear to leave or to reverse on to.
- Inside light, facing dock staff: green means the trailer is in place and it is safe to open the door and load; red means do not open the door or enter the trailer.
Lights can be switched in three main ways:
- Manually, by a switch beside the door, relying on dock staff to change it at the right moment.
- By door position, so opening the door automatically turns the outside light red.
- By the restraint, so the light only changes when the trailer is physically held.
Towns we cover in Derbyshire
We provide dock traffic lights and interlocks right across Derbyshire. Pick the town closest to your site from the list below.
- Derby
- Chesterfield
- Long Eaton
- Ilkeston
- Swadlincote
- Staveley
- Belper
- Heanor
- Alfreton
- Dronfield
- Ripley
- Buxton
- New Mills
- Glossop
Budget range for supply and fit. The written quote after a free survey is the fixed price. All guide prices.
Planning, building control and safety law in England
Workplace safety in England is regulated by HSE. For a loading bay in Derbyshire, that means doors meeting regulation 18 of the Workplace (Health, Safety and Welfare) Regulations 1992, equipment maintained under PUWER and suitable safeguards against vehicles driving away too early. We check what applies at survey and design the bay accordingly.
Questions
Will you deal with building control and planning for a project in Derbyshire?
We check at survey whether the work is likely to need approval. Forming a new opening or dock pit may need Building Regulations approval, a building warrant or building control approval, depending on the nation, and external structures such as loading houses can need planning permission. Where approval is needed, we explain what is involved, work with your designer or agent, and build it into the programme.
Do you cover Derbyshire for dock traffic lights and interlocks?
Yes. We take on dock traffic lights and interlocks for businesses in Derbyshire and across Derbyshire. We survey the site, provide a fixed written quote and manage the installation, with specialist installation engineers working under our management. Visits are arranged in advance at a time that suits your operation, and the same single contact stays with the job through to handover.
Are dock traffic lights enough on their own to stop drive-away?
Traffic lights on their own are a signal, not a physical barrier, so they depend on drivers obeying them. HSE lists traffic lights among the measures against early drive-away, and many sites combine them with key or paperwork control or with a vehicle restraint. The right combination should come from your workplace transport risk assessment.
Do traffic lights and interlocks need maintenance?
Yes. Lights, sensors and interlocks should be checked at each planned service visit, including testing the full sequence and confirming that steps attempted out of order are blocked. As part of the dock equipment they fall under PUWER, which requires work equipment to be maintained in a safe condition.
Other services in Derbyshire
Full guide to dock traffic lights and interlocks · All loading bay services in Derbyshire

