Grades of FA under BS 5839 part 6.

[Tom Sutton]

Under BS 5839 part 6 grade A, D,E, F are clear to me but B and C in practical terms confuse me.

Is grade B the same as grade A but you can lower the standard by using appendix C of part 6?

Is grade C a mismatch of interconnected FA detectors and/or smoke detectors fed by a single electric supply with backup and would interconnected grade D smoke detectors be a grade C?

[Bill J]

From memory,

Grade B allowed a lower standard of Fire Alarm Panel to be installed, as the monitoring requirements for "bigger" systems was likely to have an increased cost, and therefore prove prohibitive, however in practice, manufacturers have only ever produced panels fully compatible with Part 1 Systems.

Grade C Systems are a reflection that detectors and alarms which are part of an intruder alarm system are acceptable, without fireproof cabling.

Interconnected Grade D detectors would not be a grade C as Grade C requires a central point of control/monitoring!

I believe that's it in a nutshell, but happy to be corrected.

Bill