Answers to the most common questions UK motorists ask about HADECS 3 speed cameras - covering how they work, whether they flash, how variable speed limits affect them, which lanes they cover, and what to do if you receive a Notice of Intended Prosecution.
SpeedCamerasUK.com does not operate any UK speed cameras and has no connection to UK Government, the Police, or any Safety Camera Partnership. We are unable to advise on individual speeding cases or the progress of a speeding offence. If you have a question not answered below, please use our contact form.
How HADECS 3 works
Does a HADECS 3 camera flash when it catches a speeding driver?
No visible flash is emitted by HADECS 3 speed cameras. The unit mounted alongside the camera emits an invisible infra-red flash that allows the camera to capture clear images at night and in low-light conditions. Motorists caught by a HADECS 3 camera will not see a flash as they pass.
What are the three small cameras mounted on the pole next to a HADECS 3 gantry camera?
The three smaller cameras on the roadside pole are used to record the variable speed limit sign in force at the moment a speeding vehicle is captured. This provides contemporaneous evidence of the speed limit displayed at the time of the offence, which is essential if a driver contests a fine.
Is HADECS 3 an average speed camera or a fixed point camera?
HADECS 3 is a fixed point speed camera - it measures a vehicle's speed as it passes the camera, not over a distance. The confusion with average speed cameras arises because HADECS 3 cameras are used primarily within variable speed limit sections of motorway, alongside systems like SPECS and VECTOR which do operate as average speed checks.
Are HADECS 3 cameras required to be painted yellow?
Yes. From October 2016 all UK speed cameras, including those on motorways, were required to be painted yellow to ensure they are visible to drivers.
Variable speed limits
Do HADECS 3 cameras operate 24 hours a day or only when variable speed limits are active?
This depends on where the camera is located and how the local Police authority operates the system. Some HADECS 3 installations enforce a fixed permanent speed limit and operate continuously. Others are used within managed motorway sections and only actively enforce the variable speed limit when it is in force. The specific operating policy for any individual camera is only known by the camera operator and the relevant Police force.
Is there a delay between a variable speed limit sign changing and the camera enforcing the new limit?
Surrey Police have confirmed there is a 1 minute delay tolerance when a variable speed limit changes, to allow drivers sufficient time to react and reduce speed safely. However, this is Surrey Police's procedure only - other forces may operate a different policy. If you have received a NIP in connection with a variable speed limit change, the issuing Police force is the correct point of contact to discuss the specific circumstances.
If I am caught speeding by multiple HADECS 3 cameras on the same journey, does each camera result in a separate offence?
In principle, each camera location represents a separate potential offence. However, prosecution decisions are made by the relevant Police force and Safety Camera Partnership, and practice varies. This is a legal question that we are not able to answer definitively - if you are concerned, seek advice from a motoring solicitor.
Lane and direction coverage
How many lanes can a single HADECS 3 camera cover?
A single HADECS 3 unit can monitor multiple lanes simultaneously - this is one of its key advantages over older fixed-point cameras. On a standard three-lane motorway, a single gantry-mounted HADECS 3 camera can cover all lanes in one direction.
Can a HADECS 3 camera on the opposite carriageway catch me?
No. A single HADECS 3 installation covers one direction of travel only. On motorways you will typically see cameras sited on the nearside of the gantry (next to the hard shoulder). Where cameras are sited on the central reservation, they may be configured for either direction, but they still target one direction at a time. Cameras on the opposite carriageway cannot record your speed.
Does HADECS 3 capture the front or rear of a vehicle?
HADECS 3 cameras capture the rear of a passing vehicle, including the rear number plate.
Can a HADECS 3 camera operate if the three small pole-mounted cameras have not yet been installed?
We do not know the answer to this with certainty - only the camera installer or operating Police authority would be able to confirm whether the main gantry camera can operate independently of the pole-mounted cameras. If you have concerns about a specific location, the relevant Safety Camera Partnership is the correct point of contact.
Fines and NIPs
I received a NIP from a HADECS 3 camera but the speed limit was changing as I passed - what can I do?
Contact the issuing Police force or Safety Camera Partnership and explain the circumstances. As noted above, Surrey Police operate a 1 minute delay tolerance when variable limits change, but other forces may differ. Ask for the photographic evidence and confirm what speed was displayed on the gantry sign at the moment the camera recorded your speed. If you are unsure how to proceed, a motoring solicitor can advise on your options.
How long do I have before I receive a Notice of Intended Prosecution?
A Notice of Intended Prosecution must be sent to the registered keeper of the vehicle within 14 days of the alleged offence. If you do not receive one within that period, the prosecution may not be able to proceed, though exceptions exist. Our NIP guide covers the process in full.
Got a HADECS 3 question not answered above? Use our contact form to send it to us. Please note we cannot provide legal advice or comment on individual speeding cases.
Disclaimer: Answers published on SpeedCamerasUK.com represent the views of the site and its contributors. SpeedCamerasUK.com is not connected to any UK Police force, local authority, or Safety Camera Partnership.
Answers to the most common questions UK motorists ask about HADECS 3 speed cameras - covering how they work, whether they flash, how variable speed limits affect them, which lanes they cover, and what to do if you receive a Notice of Intended Prosecution.
No visible flash is emitted by HADECS 3 speed cameras. The unit mounted alongside the camera emits an invisible infra-red flash that allows the camera to capture clear images at night and in low-light conditions. Motorists caught by a HADECS 3 camera will not see a flash as they pass.
This depends on where the camera is located and how the local Police authority operates the system. Some HADECS 3 installations enforce a fixed permanent speed limit and operate continuously. Others are used within managed motorway sections and only actively enforce the variable speed limit when it is in force. The specific operating policy for any individual camera is only known by the camera operator and the relevant Police force.
A single HADECS 3 unit can monitor multiple lanes simultaneously - this is one of its key advantages over older fixed-point cameras. On a standard three-lane motorway, a single gantry-mounted HADECS 3 camera can cover all lanes in one direction.