Lockdown activation: Why the first action matters under Martyn’s Law

STI explains why effective lockdown activation, clear procedures and reliable emergency communication are central to Martyn’s Law readiness

Martyn’s Law has changed the tone of the public safety conversation. For many organisations, the question is no longer whether an emergency plan exists somewhere in a folder, but whether staff, systems and occupants would know what to do when a fast-moving incident unfolds.

The Terrorism (Protection of Premises) Act 2025, commonly known as Martyn’s Law, is intended to improve organisational preparedness and protective security across the UK. For the fire, safety and security sector, its implications are practical. Lockdown, invacuation and mass notification are moving from specialist conversations into wider public protection planning.

It also raises a question every installer, specifier, integrator and responsible person will recognise: when a procedure has to begin, what is the first physical action? Home Office modelling has estimated that around 179,000 UK sites will fall within scope of Martyn’s Law.

ProtectUK states that the Standard tier applies to premises expecting 200–799 people, while the Enhanced tier covers premises and qualifying events expecting 800 or more. The Enhanced tier introduces additional requirements around public protection measures, documentation and senior responsibility.

Lockdown activation and multi-hazard response

Fire safety has long had a familiar rhythm: detect, alert, evacuate. Lockdown changes that rhythm. There are scenarios where moving people out of a building may not be the safest response.

The appropriate action may instead be to keep people inside, move them away from danger, restrict movement, secure entrances or communicate instructions quickly to different groups.

This is where invacuation and lockdown enter the life-safety conversation. “False fire alarms have taught the industry that repeated unwanted alarms can erode confidence.” The Fire Industry Association (FIA) defines invacuation as remaining in or returning to a building for safety, while immediate lockdown prevents movement into, within or out of the building.

At European level, Euralarm has published guidance on using fire detection and alarm systems for lockdown. It covers scenarios including intruders, violent incidents, flooding and nearby external hazards.

The guidance, which Safety Technology International (STI) contributed towards, reflects a wider shift towards multi hazard safety planning. Lockdown is not a standalone product category. It sits within a broader approach in which fire, security and emergency communication systems need to be coordinated. The FIA guidance makes the point in practical terms.

Where a building contains alarm systems associated with hazards other than fire, the various hazard alarms need to be properly coordinated and distinct. Priorities must be assessed so a higher-priority alarm is not prevented or obscured by a lower-priority one. Ultimately, people must understand what a signal means and what action it requires.

Why lockdown activation matters

Before a lockdown message is sent, doors are secured or occupants move or remain in place, someone has to initiate the response. That person may not be calm and the environment around them may already be confusing.

This is why the activation point deserves careful attention. It needs to be recognisable enough for the right person to act quickly, while deliberate enough to prevent casual or accidental activation.

It must also be protected from misuse, damage and tampering. If it is connected to a wider system, that connection needs to be dependable. Depending on the site, activation could involve a manual call point with lockdown-specific text, a key switch for authorised staff, a push button inside a protective cover, or a device connected to a wider mass notification platform.

If the first action is unclear, everything that follows becomes harder.

Managing false lockdown activation

False fire alarms have taught the industry that repeated unwanted alarms can erode confidence.

People hear an alarm and assume it is another false call. The danger is complacency. Lockdown presents a different behavioural risk. A false lockdown activation could instead create immediate fear, confusion or panic.

This strengthens the case for getting the details right. Device location, staff training, signage, reset method, cover choice, alert tone, visual indication and escalation all need to be considered together.

An activation point should be easy to use when genuinely needed, but not so exposed that it invites accidental or malicious operation. This is familiar territory for STI. In 1978, Jack Taylor developed the original Stopper® in response to a Detroit school’s false alarm problem.

The principle was simple: protect the alarm without preventing legitimate emergency use. More than four decades later, the same thinking can be applied to a new generation of lockdown activation devices.

Designing effective lockdown activation

Lockdown will not be delivered in one way. Some sites will use dedicated lockdown systems. Others may use existing fire alarm infrastructure where appropriate, while others will rely on mass notification, access control, public address, security management platforms or a combination of technologies.

In all cases, the physical point of activation still has to sit somewhere within the design. Colour distinction can help, as can clear text. Blue is not mandated by Martyn’s Law, and there is no single universal lockdown marking.

Even so, blue has increasingly become an industry convention for distinguishing lockdown activation from red fire activation measures can help maintain confidence in the signal.

The alerting layer should not be overlooked. Where a risk assessment and system design call for local lockdown alerting, audible and visual signalling can help differentiate lockdown alerts from other site warnings, provided the wider system is properly designed and coordinated.

Physical protection may also be important where sounders, beacons or sirens could be damaged, misused or deliberately interfered with.

Preparing for lockdown activation under Martyn’s Law

Martyn’s Law will not be delivered by products alone. It will require risk assessment, planning, training, communication and review. Responsible persons will need to understand their premises, occupants and the procedures appropriate to their circumstances.

But when a lockdown procedure depends on a physical point of activation, the details matter. The effectiveness of the wider response can depend on whether the first person who recognises a threat knows what to do, can identify the correct activation point and can use it without hesitation.

As organisations prepare for the next phase of public protection planning, that first practical step deserves as much consideration as the systems that follow it.