What happens when an alarm is triggered?

All client systems benefit from a double redundant monitoring system. When an alarm is activated, an alert is sent directly to our control room for investigation and a decision will be made as to whether a response is required. As a safeguard to ensure that no alarm events are ever missed, our alarms also report directly to an NSI Gold alarm receiving centre.

If there is a confirmed alarm and we have found a situation on site requiring action, or if there has been theft, we notify the client. For all ‘false’ alarms we will not contact you.


Because we provide temporary security systems for the construction industry only – unlike the many providers also selling domestic and commercial alarm systems in need of monitoring – we can focus on looking after a relatively small number of alarm systems.

In addition, our unique RaiderVision security system uses very high quality detectors that are immune to temperature changes, bad weather and small animals. The RaiderVision system cameras are also unique in that they are mounted 1.2m above the ground, instead of at the top of a five-metre pole as with other systems. These unique features combine to result in an extremely stable security system with unprecedented low false alarm rates.

We know from our good working relationships with a number of national alarm monitoring stations that it’s not uncommon for alarm receiving centres (ARCs) to have more than 1,000 false activations from some systems in one day! On average, from the 1000+ cameras we currently have on sites across the UK, we receive an average of ten false alarms each day – with most of these caused by staff during site opening and closing times. As a result, our control room staff have plenty of time to thoroughly investigate every alarm activation properly.

How does RaiderVision deal with alarm activations?

When an alarm is triggered, our control room receives video in 30 seconds. If the activation is false, a note is made on the control system page for that alarm and no further action is taken.

If an alarm event is confirmed, meaning an intruder is on site, our control room staff immediately send an SIA-certified rapid response guard to the site and call police. Typically, a response is on the way within two minutes of the alarm activation.

In more than 99% of alarm cases, RaiderVision’s high-power siren scares off intruders and we find that no damage or theft has occurred, which is obviously the preferred outcome for all parties. On the rare occasions gates and fences are damaged or cabins, buildings or plant on site stolen or damaged, we contact client site managers immediately to activate tracking or to advise on making the site secure until morning.

Only when a site is deemed ‘clear’ after all of the above actions are complete is the event closed down, logged and reported. This ensures that we know exactly what has happened, from the moment the alarm is triggered to the moment the guard leaves the site. It allows us to understand the unique issues that each of our sites experiences on a daily basis, which in turn allows us to better advise clients on the number of cameras needed, as well as on issues such as fencing and weak spots in boundaries, all of which greatly improve the security of the site.

Generally we are able to provide a quotation from a combination of client plans and Google Earth information. If site plans are not available or if a site is large or complex, we are happy to carry out a full survey and security risk assessment. At the same time, a full health and safety survey will be undertaken or, if the quotation was provided based on site plans, the health and safety survey will be conducted on the day of installation, before the equipment is installed.

Construction site system design

There are two fundamental methods for securing construction sites or remote compounds:

1. Full perimeter system

This deploys cameras around the entire perimeter of the site, to ensure nobody can get in without being detected. This generally requires more cameras than option two:

2. Trap protection

This deploys cameras to cover key areas of the site such as gates, cabins, tool store, fuel bowser and plant parking area, and is the most popular option. Whilst it allows people to access the site over boundary fences, for example, on foot, they are detected when approaching the key areas. Once a site gets to the first fix stage, additional cameras can be added to also cover newly built structures if required.