Lockdown, invacuation or evacuation? What each means for a school

Evacuation gets people out. Invacuation brings them in. Lockdown stops anyone getting in or out. Most schools have practised the first for years. Under Martyn's Law, every school expecting 200 or more people on site will need procedures for all three, and for the fourth that holds them together: communication.

The duties are expected to start in spring 2027. Here is what each procedure means, when you would use it, and how to practise without frightening pupils.

The four procedures at a glance

How to choose in the moment

The statutory guidance gives a simple rule of thumb: if the threat seems to be inside, evacuation may be best; if it seems to be coming from outside, invacuation, lockdown or both may be more appropriate.

In practice, procedures often run one after another. A school might bring everyone in from the field, then lock down. Or it might lock down first and evacuate part of the site once it knows where the danger is. The guidance asks you to decide in advance:

• Who can start each procedure, and who deputises when they're off site.
• How the emergency services are called, by whom, and with what information.
• How procedures link together, and how you reassess as things change.
• How staff learn their role, and how the procedures are tested.

Our free lockdown, invacuation and evacuation procedures template takes you through each of these decisions and gives you one place to record them.

Why the signal matters

A lockdown signal must be different from the fire alarm, or staff may do the opposite of what's needed and lead pupils outside. The DfE's protective security guidance for education settings says the lockdown alert "must differ in some way from the actual fire alarm sound", and the statutory guidance advises against using the normal fire alarm to evacuate during an attack.

Think too about who hears it. A loud signal reaches everyone, including an intruder. The DfE's own lockdown template advises silent communication wherever possible when an intruder may be close. Most schools need both: a way to reach every adult quietly, and a way to reach people outdoors and at break.

Practising without frightening pupils

Neither the DfE nor the Home Office sets a required number of drills. The guidance asks for a rolling programme of testing, and the DfE's security guidance says practice drills show where improvements can be made. Its protective security guidance notes that drills involving primary and early years pupils are relatively uncommon, so many schools start with staff-only drills and table-top exercises.

• Start with staff. Walk through a scenario around a table before any live drill.
• Tell parents first. Explain what a drill is for and how you'll talk to pupils about it.
• Keep it calm. Frame it as "staying safe inside", and practise at different times of day, including break.
• Plan for pupils with additional needs. A personal plan for each pupil who needs one, as you would for a fire evacuation. See how SEND schools keep it calm.
• Write down what you learn. Record each drill and what you changed afterwards.

Where teamSOS fits

teamSOS Lockdown covers all four procedures. Any member of staff can raise the alarm from a phone, tablet or computer. Leaders send a Lockdown or Evacuation Announcement to every staff device in seconds, silently if they choose, and staff reply I'M OK or I'M NOT OK so the response team can see who needs help. Drill Announcements are labelled TEST, and every drill leaves a record you can export.

Sources: Terrorism (Protection of Premises) Act 2025 statutory guidance (Home Office, updated 25 August 2026); Protective security and preparedness for education settings (DfE, April 2025); School and college security (DfE, updated 3 July 2026); How Martyn's Law will affect education settings (DfE); the SIA on its role as regulator (July 2026).