Dr Zzeus Q&A: When extending or modifying a fire alarm system, what does BS5839-1:2025 actually require, and where do engineers get it wrong?In this regular column, Dr. Tom Brookes, MD at Zzeus Training and Chairman of the BSI Technical Committee FSH 12/1 Installation and Servicing, answers your questions related to fire safety. In this month’s edition he offers advice on extending or modifying existing fire alarm systems. Q: When extending or modifying a fire alarm system, what ...The post Dr Zzeus Q&A: When extending or modifying a fire alarm system, what does BS5839-1:2025 actually require, and where do engineers get it wrong? appeared first on Professional Electrician.