- Location
- Sutton, Greater London
- Main postcode districts
- SM1 and SM2
- Nearby (straight line)
- Worcester Park (3 miles), Epsom (3 miles) and Croydon (5 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.
What should sites in Sutton consider?
Distribution centres near Sutton taking trailers from many different hauliers benefit from a signal every driver understands, regardless of language or familiarity with the site. New warehouses in Sutton can have lights and interlocks wired in during the electrical fit-out, avoiding retrofit cabling and keeping every bay on one control standard.
Sites around Sutton 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 Sutton 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.
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.
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.
The same published guide range applies across England; access, out-of-hours working and site conditions are confirmed at the free survey.
What does the free survey cover?
- Asbestos register and any other site hazard information
- Lighting inside trailers and at the dock face
- Access for deliveries, cranes or lifting equipment during installation
- Wheel guide positions and yard markings for reversing vehicles
- Gaps around trailers where heated or chilled air escapes
- How drivers are prevented from pulling away too early
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.
Door-linked lights
Lights that change automatically with the door position, using a door switch or a signal from the door control panel, so the outside light turns red as the door opens.
Regulations and approvals in England
Workplace safety in England is regulated by HSE. For a loading bay in Sutton, 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 Sutton
Do you remove and dispose of the old equipment?
Yes, where it is part of the scope. When we replace doors, levellers, shelters or seals at a site in Sutton, removal and disposal of the old equipment can be included and is itemised in the quote, so it is clear what is covered. If anything should be kept, such as a frame or motor that is still serviceable, we agree that at survey.
How do you price dock traffic lights and interlocks for a site in Sutton?
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.
Is the site survey in Sutton free?
Yes. For new installations, replacements, upgrades, conversions and complete bays, the site survey and written quote are free and come with no obligation. The survey lets us measure the openings, check the dock and structure, and understand how the bay is used, so the quote reflects your site. Repair and servicing visits are different: they are chargeable, with the price agreed before anyone attends.
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 Sutton
Looking beyond Sutton? Our pages for Worcester Park (3 miles), Epsom (3 miles) and Croydon (5 miles) describe the same loading bay services and how to get in touch.
Other loading bay services in Sutton
Full guide to dock traffic lights and interlocks · Everything we do in Sutton
If a loading bay in Sutton needs attention, call us or send photos and details online.