Part 3: Confirmed activations

All new alarm systems installed since 1 October 2001 - and any older systems that have subsequently had police response withdrawn - must be able to provide "confirmed activations" in order to ensure a police response.

A confirmed activation is one where shortly after an ARC receives an initial alarm signal, a further signal is received that leads the ARC to conclude that a genuine break-in is underway.

This further signal can be provided by:

> Audio/Visual verification - Sounds or pictures are transmitted to the ARC.

> Sequential verification - Two or more alarm detectors activate.

> Known loss of two signalling links.

> An alarm activation followed by known loss of a signalling link (or vice versa).

The key difference between "confirmation systems" and those commonly referred to as "non-confirmation systems" is as follows:

Non Confirmation Systems - These comprise most currently installed Type A alarms. The 1st activation of the alarm electronically 'locks' the system and signals this fact to the ARC - which would in turn request that police and keyholders attend.

Confirmation Systems - These do not 'lock' themselves after sending an alarm signal to the ARC. Instead, they remain able to provide further signals in an effort to indicate whether the initial alarm signal is likely to relate to a genuine break in.

With such systems ARC's only request a police response to confirmed activations. In the event of an unconfirmed activation only keyholders would be asked to attend.

Rules for the design, installation and operation of alarm systems able to generate confirmed activations are contained in a draft British Standard known as DD243 2004.