Lockdown for a building you can't lock: what the guidance actually says
In short
Lockdown does not mean shutting the whole building, and it does not require buying new locks. A single lockable room, or stopping people using only the doors nearest the danger while leaving others open, can meet the duty. The guidance calls these partial lockdowns, and treats them as a normal, often better, answer for smaller premises.
Key points
Lockdown is the duty in section 5(3)(c) of the Act: procedures "for preventing individuals entering or leaving the premises".
A full lockdown closes every way in and out; a partial lockdown closes only some, deliberately leaving others open.
There is no legal requirement to buy new locks or equipment to do this.
The guidance does expect you to think about modest, low-cost changes — like how a door is bolted — where that helps you implement the procedure.
If you cannot lock the outside of the building at all, moving people to an internal room that can be shut and held is still a lockdown procedure.
What the law actually asks for
Section 5(3)(c) is the duty to have procedures "for preventing individuals entering or leaving the premises". The statutory guidance, at paragraph 7.43, splits this into two kinds: "a full lockdown prevents people from entering or exiting the premises … a partial lockdown involves only locking certain entry and exit points while keeping others operational, for example, allowing people to escape in a safe direction." Paragraph 7.41 adds that "a partial lockdown may also be used to secure parts of the premises … if an attack is occurring within a different part of the premises."
So lockdown is not an all-or-nothing idea. Locking the door on the side the danger is coming from, while leaving another door open as a way out, is itself a lockdown procedure — and for many halls with one main entrance and one fire exit, it may be the only realistic one.
No new locks required — and some small changes might be worth it
There is no separate duty at standard tier to buy equipment or alter the building. Paragraph 7.25 is direct about this: "there is no statutory requirement in the Act to make any physical alterations or to purchase specific equipment relating to putting public protection procedures in place." The same paragraph goes on to say that such changes "may be reasonably practicable" in some cases, giving "changing how doors are locked or altering the location of shutter controls" as its own examples. That is a long way from a duty to fit new locks — it simply means a cheap, sensible change is worth considering if it helps a procedure actually work, not that one is required.
If you can't lock the building at all
Paragraph 7.44's third bullet makes an important practical point: some entry and exit points "could have provisions to enable them to be unlocked for the purposes of fire evacuations (in some cases, automatically)", so a building that looks locked down may not stay that way if the fire alarm sounds. The guidance's own worked example, also at 7.44, shows a school moving people to "a pre-designated safer area" that "can be secured from within and there are no windows" — an internal-room lockdown, used because the building's outer doors could not be relied on. That is a legitimate lockdown procedure in its own right, not a fallback for failing to meet the duty.
Common questions
- Do we have to buy new locks to have a lockdown procedure?
No. There is no requirement to buy equipment or make alterations. A procedure that uses what you already have — including moving people into a room that can be shut — can meet the duty.
- We only have one usable door. Can we still lock down?
Yes. Holding or avoiding that one door, or moving people to a single room that can be held, is a partial or internal-room lockdown — both are recognised in the guidance, not just a full building lockdown.
- Is lockdown the same as invacuation?
No. Lockdown is about who can get in or out. Invacuation is about where people go to be safer inside. They often work together, but the Act treats them as two separate duties.
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Sources
Last reviewed 2 November 2026, against the statutory guidance of 15 April 2026 (corrected 6 August 2026).