Mobile site surveillance: off-grid CCTV for construction sites

On a construction site, materials, machinery and cable drums sit out in the open for months. At night and at weekends nobody is there, the fence has gaps, and the site entrance shifts with every phase of work. Operators of properties and facilities face a similar task when an area needs temporary protection – during refurbishment, after an incident or for a special situation.

This article explains why fixed CCTV rarely fits such sites, what a mobile solution has to deliver, and what to bear in mind on data protection.

The problem: fixed systems don’t suit a building site

Conventional video systems are built to last for years, with cabling for power and data and permanent poles. Construction sites usually have neither. By the time power and data are in place, part of the work is already finished – and today’s site boundary may be in the middle of the shell in three months’ time.

Then there is day-to-day operation. A camera nobody watches stops nobody. Anyone asked to monitor twenty feeds at once overnight will miss the one that matters. And clients, insurers and authorities want to know afterwards what happened, when, and who responded.

What mobile surveillance needs to deliver

Off-grid: power and radio on board

The equipment must work without a mains connection or data cables. That means its own power supply at the mast and radio links from mast to mast and on to the control room. Ask how long the supply lasts without recharging. Our article on planning cameras, loudspeakers and radio on site covers routing radio links around buildings and cranes.

Relocatable as the work progresses

Protection has to move with the site. Mobile masts should be set up and moved within hours – no foundations, no electrician. Plan positions by construction phase: where are the material store, the site entrance and the hazardous area in each phase?

Around the clock, including at night

Most theft and unauthorised entry happens when nobody is around. At night you need either enough light in the image or cameras with night vision. Lighting on the mast also deters intruders and makes people clearly visible.

Matching camera and position to the task

Not every camera has to show every detail. EN 62676-4 links each task to a minimum pixel density at the target:

Task under EN 62676-4	Pixels per metre at the target
Detect – is someone there?	25
Observe – what is the person doing?	62.5
Recognise – is it someone known?	125
Identify – who is it?	250

Along a fence line, detection or observation over a longer distance is often enough; at the site entrance a higher density may make sense. The further away a person is, the fewer pixels fall on them – so a camera’s useful range depends on the task.

Perimeters and restricted areas that raise alerts

Rather than watching feeds, define the areas nobody may enter: fence line, material store, excavation, track, roadway. When someone enters, the guard needs an alert – with the location and a photo showing what is going on. Brief disturbances should not trigger alarms, nor should one situation be reported every second.

Speaking to intruders over a loudspeaker

Many intruders leave as soon as they are addressed. A loudspeaker on the mast turns the camera into a voice on site: “You are on a closed site. Please leave the area.” The announcement should be targeted at the mast concerned – spoken live or as a prepared message.

Linking in the control room and security patrol

The alert has to reach whoever can respond: your own security control room, the guarding company or the patrol’s phone. Agree early on who is responsible at night and how quickly someone can be on site.

Several sites

Several sites or properties call for one shared interface rather than a separate system for each.

Data protection: as little as possible, as much as necessary

Video surveillance processes personal data. Private operators usually rely on legitimate interests under Art. 6(1)(f) GDPR; in Germany, Section 4 BDSG also applies to publicly accessible areas. The guidance from the German data protection authorities and the EDPB’s Guidelines 3/2019 stress the same points:

• Define the purpose and limit surveillance to it – for example protection against theft and unauthorised entry.
• Minimise data: capture only what is needed and keep it no longer than necessary (Art. 5 GDPR).
• Avoid other people’s land such as neighbouring plots and public footpaths wherever possible.
• Put up signs identifying the controller and the purpose (Art. 13 GDPR).
• For extensive surveillance, consider a data protection impact assessment (Art. 35 GDPR).

The most effective technical measure is not to record video at all and to store only a photo as evidence when a warning is raised.

How MOVETOS OPS helps

The MOVETOS SET consists of masts with camera, lighting and loudspeaker, independent of mains power and the network. The masts bring their own power and radio and can be moved as the site progresses. The MOVETOS OPS platform brings camera images, alerts and announcements together on one map.

You draw restricted areas directly on the map. MOVETOS OPS transfers each area into the image of every camera that can see it; if no camera covers an area, the map shows that too. When a person stands inside one for at least three seconds, MOVETOS OPS raises “Person in restricted area” with an evidence photo – at most once a minute per area. The alert appears in the control room and as a notification on the phone. The AI runs on site on local hardware; no cloud is required.

An alert does not start an announcement on its own. The system suggests, a person approves: the guard sees the photo, decides, and speaks at the mast concerned – live into the microphone or with a prepared message in up to five languages, even without internet. At a large family festival, MOVETOS supported the night watch in exactly this way with automated area monitoring.

The live picture runs where your security service works, or in the mobile MOVETOS control room on site. At Munich Airport, MOVETOS OPS is linked to the security control centre, with data transmission across the entire airfield. At the Bundeswehr Open Day, up to 15 sites and 45 ha of barracks were connected without cables. Your team can reach the control room even without mobile coverage, over the local network on site. Every deployment is documented in a complete record: each alert, approval and announcement with time and evidence.

On data protection: MOVETOS OPS records no video. It stores figures without personal reference and, for warnings, an evidence photo that is deleted three months after the deployment ends. Image areas such as neighbouring plots can be marked as privacy zones and are blacked out before analysis. Team members with the on-site role see no camera images on their own phones.

Checklist for your site or property

• Set the protection goal: what needs protecting – materials, machinery, the entrance, hazardous areas?
• Plan by phase: where will the masts stand in each construction phase, and how often will they move?
• Check self-sufficiency: how long does the equipment run without power or network, including in bad weather?
• Calculate pixels: is the resolution at the fence enough to detect or observe under EN 62676-4?
• Think about night-time: is there lighting on the mast or night vision on the camera?
• Draw restricted areas: which areas must nobody enter, and is each one covered by a camera?
• Agree the response: who receives alerts at night, who speaks over the loudspeaker, who goes out?
• Test for failure: do alerts, announcements and communication still work if mobile coverage or a radio link drops out?
• Settle data protection: purpose, signage, no video recording, excluding other people’s land, deletion periods.
• Keep the evidence: is every alert recorded with time, photo and response?

Conclusion

Construction sites and properties need protection that is as mobile as the work itself: self-sufficient, quickly relocated, active around the clock. What counts is not the number of cameras but the chain behind them – defined restricted areas, an alert with an evidence photo, a loudspeaker announcement and a control room that responds. Doing without video recording and excluding other people’s land protects the site and takes data protection seriously.