Alarm Signalling Standards

Everything you need to know

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:

Fire Standards

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 – DP4 (CS.54.RR4).

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.

Before 1st June 2019 – Old ATS Grade (EN50136-1:1998)

ATS Grade Catastrophic Failure Reporting
Grade 2 25 hours
Grade 3 60 mins
Grade 4 6 mins

From 1st June 2019 – Single Path (SP) or Dual Path (DP) Equivalent (EN50136-1:2018/PD6669:2017/PD6662:2017/BS5839-1:2025)

Single Path (SP) Dual Path (DP) Catastrophic Failure Reporting
SP2 DP1 25 hours
SP3 DP2 31 mins
DP2+ 11 mins
DP3 4 mins
DP4 3 mins

Our Alarm Signalling Range

EN SP & DP Classes Catastrophic Failure Reporting Solution Paths
SP2 12 hours MiniAir 2 Radio Only
SP2 25 hours DigiAir Pro 3 Radio Only
LAN Only
SP3 31 mins DigiAir Pro 3 Fire Radio Only
DP2 31 mins GradeShift Pro 4 Radio + Radio
LAN + Radio
DP2 31 mins GradeShift Pro 2 Fire Radio + Radio
DP2+ 11 mins GradeShift Pro 4 Radio + Radio
LAN + Radio
DP3 4 mins GradeShift Pro 4 Radio + Radio
LAN + Radio
DP4 3 mins GradeShift Pro 4

LAN + Radio

Radio + Radio

DP4 3 mins GradeShift Pro 2 Fire

LAN + Radio

Radio + Radio

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