Mobile CCTV towers (solar/4G) for construction sites

• Mast: lifts the cameras to see over fences, containers and stockpiles, and out of reach.
• Cameras: fixed views of specific areas, often with thermal cameras for the night. The choice depends on what has to be seen.
• Power: a solar panel charging a battery; some models add a backup generator or fuel cell.
• Link: a mobile (4G) router that sends video and alerts.
• Detection: video analytics that pick out a person or vehicle inside a defined zone.
• Speaker and light: the operator can talk down an intruder or switch on a floodlight.

The tower is a tool for detection and deterrence, not guarding in itself. For how video analytics work and why they make mistakes, see the guide to video analytics.

• No power: early in a project the supply often isn’t there yet, or doesn’t reach the perimeter.
• Changing layout: the tower moves to where the materials and plant are now.
• Short projects or phases: it goes up and comes down without leaving cables or bases behind.
• Large perimeter: a few towers give a view of ground no single guard can see at once.

Where there is a busy gate or high-value material, the tower adds to the guard rather than replacing them — the comparison of static guards, patrols and remote monitoring is in the guide to construction site theft. For the hours the site stands empty, see night and weekend site security.

• Winter: short, cloudy days mean less charging, while the nights — the hours that matter — are longer. Ask how many sunless days the unit lasts and what happens when the battery runs low.
• Signal: if 4G is weak at that spot, video arrives late or not at all. Ask for a signal measurement at the tower’s actual position, not at the office.
• Vandalism: the tower is visible, so it is also a target. Ask for tamper, tilt or movement alerts.
• False alerts: rain, wind, animals, vegetation and car headlights trigger detection. Zones are tuned, and re-tuned as the site changes.

A tower that powers down or loses its link must say so. Make sure low battery, lost connection and tampering reach the monitoring centre as alerts — otherwise silence looks like calm.

1. Detection: the camera spots movement in a zone and sends an alert with images.
2. Verification: a person judges whether it is an intruder, a worker who forgot something, or an animal.
3. Deterrence: a spoken warning through the speaker, or light.
4. Response: a patrol or keyholder, and the police where the procedure says so.
5. Report: what happened, what was found, what is still open in the morning.

How this chain is set up, and what happens when the link drops, is covered in the guide to remote guarding. What is specific to a construction site: the contact list and the zones change with the project, so name who updates them every time a tower moves.

A tall mast sees a long way, so the position and angle of every camera are a legal question, not just a technical one. Directive 1/2011 sets out:

• Streets and pavements (art. 6 §1): capturing adjacent streets and pavements is prohibited; by exception it is allowed only at places with increased security needs, and then only the strictly necessary adjacent area.
• Neighbours (art. 6 §2): capturing the entrances or interiors of neighbouring homes, buildings or other spaces is prohibited.
• Pan-and-zoom cameras (art. 6 §4): allowed only where movements are watched in real time so that someone can intervene at once — the Directive’s example is night security of large premises — and with technical limits on the field of view, such as privacy masking.
• Audio (art. 6 §5): processing audio data is prohibited, except in exceptional cases the Authority approves. A speaker for warnings is not the same as recording sound — ask whether the tower has a microphone and require that it does not record.

Ask for a plan showing each camera’s field of view on the site map, with masks wherever it catches a road or a neighbour. The Authority also points out that video surveillance may not be used to monitor or evaluate employees (art. 27, Law 4624/2019; Hellenic DPA) — the tower is there for the site when it is empty, not for the work crews.

• Coverage plan: how many towers, where, what each one sees, which detection zones and which masks.
• Power and signal: autonomy without sun, a signal reading at the spot, what happens when the battery runs low.
• Fault alerts: battery, link, tampering — and who receives them.
• Verification and response: who watches the alerts and during which hours, the contact list, and when the police are called.
• Signs: clearly visible, before the camera’s field of view, naming the controller, the purpose and whom to contact (art. 12) — see the guide to the CCTV sign.
• Retention: deletion within 15 working days at most if nothing happens; 30 days for an incident against you, 3 months if it involves a third party (art. 8) — details in the footage retention guide.
• Roles: who is the data controller (the client or the main contractor) and who processes the footage on their behalf.
• Moves: who decides the new position when the project enters a new phase, and that the coverage plan and masks are updated with it.

For construction sites, OVIT designs turnstile access, mobile CCTV towers and patrol response (construction site security). In the Guardly platform, patrols, incidents and reports appear in one live picture.