- Location
- Grays, Essex
- Main postcode district
- RM17
- Nearby (straight line)
- Tilbury (2 miles), South Ockendon (3 miles) and Gravesend (3 miles)
- Survey and quote
- Free, with a fixed written quote
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.
Why do sites in Grays choose this?
If a site in Grays 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 Grays with inflatable shelters often add interlocks so the shelter only inflates once a trailer is docked and restrained.
Sites around Grays that run night shifts often find traffic lights easier for drivers to read than staff waving or knocking on the cab door.
Our part of the job in Grays 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.
In the wider area around Grays, the Port of Tilbury and the London Gateway port are both in Thurrock, the borough that includes Grays. Docks with frequent trailer movements put more cycles on doors and levellers, which is why planned servicing matters.
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.
The same published guide range applies across England; access, out-of-hours working and site conditions are confirmed at the free survey.
What do we check at the survey?
- Age and condition of the equipment already in place
- Control positions, isolators and any existing interlocks
- Asbestos register and any other site hazard information
- How drivers are prevented from pulling away too early
- Forklift and pallet truck loads crossing the leveller platform
- Wind exposure at the dock, which affects door and shelter choice
Options to discuss
Restraint interlock package
Door, lights and vehicle restraint tied together so the door only opens once the trailer is held and the restraint only releases when loading is finished.
Standalone LED traffic lights
A red and green pair for each bay, one outside for the driver and one inside for dock staff, switched manually from a control beside the door.
What do the rules in England mean for the work?
Workplace safety in England is regulated by HSE. For a loading bay in Grays, 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 about dock traffic lights and interlocks in Grays
Do you cover Grays for dock traffic lights and interlocks?
Yes. We take on dock traffic lights and interlocks for businesses in Grays and across Essex. 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.
What warranty comes with new loading bay equipment?
New equipment comes with the manufacturer's warranty, which varies by product. Our workmanship terms are set out in writing in the quote for your Grays site, so you can see what is covered before you commit. Check the warranty terms for any servicing conditions, and we can quote for planned maintenance once the installation is complete.
How do you price dock traffic lights and interlocks for a site in Grays?
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 interlocks be fitted to a manual loading bay door?
Yes. A door position switch fitted to a manual door can confirm when it is fully open or fully closed. That signal lets the traffic lights change automatically and stops the leveller being raised until the door is out of the way.
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.
Dock traffic lights and interlocks near Grays
Sites close to Grays get the same service, including those in Tilbury (2 miles), South Ockendon (3 miles) and Gravesend (3 miles), with every job run the same way.
Other loading bay services in Grays
Full guide to dock traffic lights and interlocks · Everything we do in Grays
Use the quote tool to tell us about the doors, levellers or shelters at your Grays site, and we will be in touch to arrange the next step.