Alarm Signalling Standards

There have been significant changes to alarm signalling standards and terminology. Grades 2, 3 and 4 now have Single Path (SP) and/or Dual Path (DP) equivalents. The catastrophic failure reporting times have also changed. Our Alarm Signalling Range operates to these standards and in some cases exceeds them.

This is how the old and new standards apply to current CSL products:

The BSI & FIA recently announced the release of the updated BS5839-1:2025 standards. As part of the update, L category installations require alarms to be delivered within the DP4 standards.

Therefore, two new Fire variants are now available to order:

• GradeShift Pro Fire – LAN + Radio – DP4 (CS.54.LR4).
• GradeShift Pro Fire – Radio + Radio – DP3 (CS.54.RR3). (This can be used for those sites where LAN is not available – using the agreed variation wording below).

Description of Variation:

A variation to BS 5839-1:2025 Clause 14.17 standard installation practice was implemented as follows:

A dual-path radio-radio signalling system with 240-second catastrophic communication failure reporting replaces the 180-second requirement.

Justification for Variation:

Site unable to provide an operational fixed-line IP connection.

Our existing fire variants are suitable for any P category installations. A reminder, they are:

• DigiAir Pro Fire – Radio – SP3 (CS.54.R3)
• GradeShift Pro Fire – Radio + Radio – DP2 (CS.54.RR2) 

If you require any further information, please contact our team.

For more information about any of these products outlined above, please visit Support. Alternatively, please contact us using the link below.