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 County Down?
New warehouses in County Down can have lights and interlocks wired in during the electrical fit-out, avoiding retrofit cabling and keeping every bay on one control standard. Food and chilled operations around County Down with inflatable shelters often add interlocks so the shelter only inflates once a trailer is docked and restrained.
Whether your unit in County Down has one dock or twenty, the survey looks at each bay's existing controls before we quote a fixed price in writing.
It starts with a free site survey in County Down, where we measure the openings, check the dock and talk through how the bay is used. You then receive a fixed written quote. Once you accept, we manage the job: specialist installation engineers carry out the work under our management, planned around your deliveries, and out-of-hours working can be arranged. At handover we test everything with you and leave the documentation.
How much do dock traffic lights and interlocks cost?
Dock traffic lights and interlocks typically cost £650 to £3,400 per bay, supplied and fitted, excluding VAT. A pair of manually switched LED signals sits at the lower end, while a full interlock panel linking door, leveller, restraint and shelter sits towards the top.
What moves the price:
- Level of control: standalone lights, door-linked lights or a full interlocked sequence.
- Existing control panels: modern door and leveller panels often accept interlocks directly; older panels may need replacing with a combined bay panel.
- Sensors: door position switches, trailer presence sensors and restraint signals each add parts and wiring.
- Cable runs: distances between lights, panels and the power supply.
- Number of bays and timing: repeat bays reduce the cost per bay, while out-of-hours working adds to it.
These are guide budgets. After a free site survey we send a written quote, and that quote is the fixed price. VAT is added at the standard rate.
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 County Down
Choose a town below to see how we handle dock traffic lights and interlocks in that part of County Down.
Budget range for supply and fit. The written quote after a free survey is the fixed price. All guide prices.
What do the rules in Northern Ireland mean for the work?
Workplace safety in Northern Ireland is regulated by HSENI rather than HSE. Loading bay doors in County Down need to meet the Workplace (Health, Safety and Welfare) Regulations (Northern Ireland) 1993, and we check what applies at survey, including the measures that stop vehicles leaving the dock too early.
Questions
How do you price dock traffic lights and interlocks for a site in County Down?
Guide budgets for supply and fit are £650 to £3,400 per bay, excluding VAT. The figure moves with size, insulation, the operator, electrics, access, any pit or groundworks and out-of-hours working. Where levellers are involved, the guide assumes an existing, sound pit. After the free survey you receive a fixed written quote, and that is the price for the agreed scope.
Can you work alongside our main contractor on a new build in County Down?
Yes. For new warehouses and fit-outs, we can supply and install the dock package as part of a wider project, working to the main contractor's programme, site rules and permits. We will need drawings, dock levels and the programme, and we coordinate pit details, power supplies and door openings with the relevant trades before installation begins.
Which way round do the inside and outside lights work?
The inside and outside lights always show opposite colours. While a trailer is being loaded, the outside light is red so the driver stays put and the inside light is green so staff can work. When loading is finished and the door is closed, the inside light turns red and the outside light turns green for the driver.
Will interlocks slow down my loading operation?
Interlocks add a fixed sequence, but each step takes only moments and staff soon get used to it. In practice many sites find the sequence saves time overall, because there are fewer arguments about when to open the door and less damage from levellers being raised into part-open doors.
Other services in County Down
Full guide to dock traffic lights and interlocks · All loading bay services in County Down