Police response to burglar alarms, explained

The police do not respond to alarms. They respond to some alarms.

This is the point on which most of the confusion in the category rests. There is no general police duty to attend a sounding burglar alarm. What exists is a framework under which forces agree, in advance, to act on signals from particular systems that meet particular conditions.

In England and Wales that framework is national policy from the National Police Chiefs' Council, applied locally by each of the 43 territorial forces. Scotland and Northern Ireland have their own equivalent arrangements under Police Scotland and the PSNI.

If your system is not inside that framework, an activation generates no police attendance. You can of course still report a crime — and if you have evidence of a burglary in progress, the police will respond to that report like any other. But the alarm itself will not summon anyone.

The four conditions

Stated plainly, a system inside the framework has all of the following. Missing any one of them means no police response.

It is installed and maintained by a company certificated by an approved inspectorate — in practice the NSI or SSAIB. It is monitored by an ARC certificated to BS EN 50518. It holds a Unique Reference Number issued by the force covering the address. And it is capable of producing a confirmed activation, because unconfirmed single-detector signals do not normally attract attendance.

That last condition is a design question, not a paperwork one, and it is the one people discover too late. A system with one detector in a hallway cannot produce a confirmed activation, so it cannot get a confirmed-activation response, whatever the contract says. If police response matters to you, say so before the survey.

How a URN is obtained

You cannot apply for one. An approved installer or ARC applies to your local force on your behalf, once the system meets the standard and a monitoring contract is in place.

Forces normally charge to issue a URN and to maintain it annually, and they set those fees locally, so they differ across the country. Ask for them itemised separately from your provider's own charges.

The URN belongs to the address, not to you. It does not move with you when you move, and a poor false-alarm history at a property is inherited by whoever occupies it next. It also depends on a current maintenance contract — if that lapses, police response can be withdrawn even though nothing about the hardware changed.

Confirmed activations

A confirmed activation is one where more than one independent indication points to a real intrusion: two separate detectors triggering, or a detector plus audio or video verification. An unconfirmed activation is a single detector firing once.

The distinction exists because single-detector activations are overwhelmingly false. A spider on a lens produces one signal. A person moving through a building produces several, in a pattern. UK system design for confirmation is covered by BS 8243.

This is also why remote CCTV monitoring is often paired with intruder monitoring on commercial sites: video gives the operator a way to verify, and verification can support confirmation.

Losing police response

Excessive false alarms get a URN suspended, and persistent problems get it withdrawn. The principle is national — police response is finite and a system that cries wolf loses access to it — but the thresholds and the way suspensions are handled are set by each force.

Suspension is not usually permanent. The normal path is that the installer diagnoses the cause, fixes it, demonstrates a clean period and applies for reinstatement, sometimes with a further fee.

The causes are consistently mundane: user error, pets, poorly sited detectors, insects, and doors or windows moving in draughts. All are cheap to fix once identified, which is the argument for reporting every false activation to your provider rather than silently resetting it.