What is a confirmed alarm activation?

A confirmed activation is one where more than one independent signal indicates a genuine intrusion — typically two separate detectors triggering, or a detector plus audio or video verification — rather than a single detector firing once. Police forces treat confirmed activations as a higher priority than unconfirmed ones.

The idea exists because single-detector activations are overwhelmingly false. A spider on a lens or a balloon in a draught produces one signal. A person moving through a building produces several, in a pattern.

In the UK, system design for confirmation is covered by BS 8243. In practice it means the system is configured so that the ARC can distinguish a lone stray signal from a sequence consistent with someone actually inside.

The consequence for you is about equipment and layout, not paperwork: a system with one detector in a hallway cannot produce a confirmed activation, however good the monitoring contract is. If police response matters to you, detector coverage needs to be planned for it from the start.

Audio and video verification can also serve as confirmation, which is part of why remote CCTV monitoring is often paired with intruder monitoring on commercial sites.