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 matters for dock traffic lights and interlocks in Suffolk?
Sites around Suffolk that run night shifts often find traffic lights easier for drivers to read than staff waving or knocking on the cab door. Loading docks in Suffolk where drivers wait in their cabs for a hand signal can replace guesswork with a clear red and green light at every bay.
Food and chilled operations around Suffolk with inflatable shelters often add interlocks so the shelter only inflates once a trailer is docked and restrained.
Our part of the job in Suffolk 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 happens on site when traffic lights and interlocks are fitted?
Fitting lights and interlocks is mainly electrical work, and each bay is out of use while its controls are connected and tested. Working bay by bay keeps the rest of the dock running.
- Fix the signals: the outside light is mounted on brackets at a height drivers can see, and the inside light beside the door.
- Run the cables: wiring is run in conduit or trunking between lights, sensors and control panels.
- Isolate and connect: the door and leveller supplies are isolated and locked off while the interlock wiring is connected, or a new bay panel is fitted.
- Test every sequence: each interlock is tested, including what happens if a step is attempted out of order.
- Brief staff: dock staff are shown the new sequence, and signs are fitted for drivers.
It helps if you can provide any electrical drawings for the dock, access to the distribution board, a person who can authorise isolations and an agreed order for releasing bays.
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 Suffolk
Choose a town below to see how we handle dock traffic lights and interlocks in that part of Suffolk.
Budget range for supply and fit. The written quote after a free survey is the fixed price. All guide prices.
Regulations and approvals in England
Workplace safety in England is regulated by HSE. For a loading bay in Suffolk, 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
Can you work outside our normal operating hours in Suffolk?
Yes, by arrangement. Evening, night and weekend working can be planned so the installation causes as little disruption as possible to your loading schedule. Out-of-hours work can affect the price, so mention it at the survey and we will include it in the written quote. The agreed times are confirmed in the programme before the job starts.
Is VAT included in your guide prices for dock traffic lights and interlocks?
No. Our customers are businesses, so guide prices exclude VAT, which is added at the standard rate. The same guide range applies in Suffolk as everywhere else: for dock traffic lights and interlocks, it is £650 to £3,400 per bay, excluding VAT. It covers supply and fit for a typical installation. Your fixed written quote after the free survey shows the net price, the VAT and exactly what is included.
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.
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 Suffolk
Full guide to dock traffic lights and interlocks · All loading bay services in Suffolk