The FIA has released an updated guidance note exploring the use of fire detection and alarm (FD&A) systems for lockdown purposes, with a specific focus on schools. This update aligns with the latest recommendations found in BS 5839-1:2025, and addresses growing interest in whether fire alarm systems can be safely and effectively used for both evacuation and invacuation scenarios.

Safety Beyond Fire

Traditionally, FD&A systems are designed solely for evacuation—removing people from a building when there’s a fire risk. But in schools and other public buildings, not all threats require people to leave. In some cases, it’s safer to stay put, such as:

• A chemical spill or toxic release nearby
• A violent intruder threat
• A dangerous animal in the area

This approach is known as invacuation, and in its most serious form—lockdown—it involves keeping people inside, restricting movement, and securing the premises. For schools, the ability to communicate such instructions clearly and calmly is crucial.

Dual Use of Fire Alarm Systems: A Growing Trend

The guidance reflects a growing industry trend: using fire alarm systems to signal both evacuation and lockdown events. While this may seem efficient—reducing costs by using a single system—it raises key considerations around clarity, system design, and compliance.

BS 5839-1:2025 now provides clear commentary on this topic. Clause 5(a) states:

“If a building contains alarm systems associated with hazards other than fire, the various hazard alarms need to be properly coordinated and be distinct from each other… The system [should be] arranged so that a higher priority alarm cannot be prevented or obscured by one of a lower priority.”

This updated standard places an emphasis on coordination and clarity, ensuring that alarms for different risks—whether fire or invacuation—are clearly distinguishable and cannot interfere with each other.

Why Consider FD&A Systems for Lockdown?

Schools considering FD&A integration for lockdowns may be drawn by:

• Cost efficiency – fewer systems to install and maintain
• High reliability – FD&A systems are robust and fault-monitored
• Complete coverage – ideal for communicating site-wide alerts

However, BS 5839-1:2025 also makes it clear: if fire alarm systems are used for other safety functions, they must be designed accordingly and with clear protocols for alarm priority and activation.

Design Considerations Under BS 5839-1:2025

The updated guidance helps schools and specifiers understand what needs to be in place to comply with the standard:

• Distinct alarm signals – Lockdown and fire evacuation alerts must be audibly and visually different
• Defined priority – Premises managers must assess which event takes precedence and ensure systems reflect that
• Clarity in case of dual activation – Procedures must exist for what to do if both alarms are triggered
• Stakeholder agreement – Plans should be made in consultation with school staff, system designers, and emergency services

Real-World Relevance

The concept of invacuation is no longer theoretical. From real lockdowns prompted by police incidents to nearby environmental hazards, schools are increasingly having to respond to non-fire emergencies. Using a familiar system that reaches every room, like the FD&A, is a natural step—but only when done safely and in line with BS 5839-1:2025.

Summary: Safety, Clarity, and Compliance

This updated FIA guidance supports schools and public buildings in making informed decisions about adapting their fire alarm systems for wider safety use. With the changes to BS 5839-1:2025, the standard now better reflects the realities many premises face and provides a foundation for safe and compliant dual-function systems.

View the Guidance Note.