Under Martyn's Law, how do we warn back-of-house staff during a lockdown?

Why a lockdown fails at the back of the building first

A lockdown is a staff action. The guidance describes it as "securing points of entry and exit, such as by locking doors, closing shutters or using other available barriers" (statutory guidance, 15 April 2026, para 7.42). The people who do that are not in the foyer. They are in the kitchen, the loading bay, the plant room and the stores, and those are the rooms with the most noise, the worst mobile signal and, commonly, a fire sounder but no loudspeaker, because the fire strategy only ever needed a tone there.

So the lockdown instruction has to reach back of house first, not last. In a lockdown, staff in back-of-house areas need instructions, not just a noise. Decide whether that means voice coverage or a defined radio procedure before any system design is finalised.

What the guidance asks you to decide

Four points from the communication procedure section of the statutory guidance, all of them about staff:

• Staff may need a different message from the public. Consider "what information should be communicated, both to members of the public and to staff at the premises, as this information might differ" (para 7.48).
• Staff need a channel to each other. Consider "how staff will communicate with each other and how information will flow between staff and decision-makers" (para 7.48).
• The method should fit the building. "Public address systems, loud hailers/megaphones, closed radio systems and alarms could be used at larger premises or events, and more basic forms of alert such as giving loud, clear verbal commands could be used at smaller premises" (para 7.48).
• The message has to arrive. Larger premises should consider "where people may be located when information is communicated and whether information will reach them effectively in those areas" (para 7.49).

And the duty behind all four: staff with a role in a procedure "must be made aware of the procedures and their specific role" and be given "the understanding, experience and tools required to carry them out effectively" (para 7.51). A kitchen porter who is expected to lock the goods-in door needs a way of being told to.

Four ways to reach back-of-house staff, compared

1. Voice coverage into staff areas. Loudspeakers in the back-of-house rooms, on a zone that can be addressed separately, carrying a staff message ("staff: lockdown procedure, secure your area") that the public need not hear. Where the voice alarm already covers those rooms, this is configuration. Where it does not, it is loudspeakers and cabling, which is usually a small addition to an existing system, not a new one. It reaches everyone at once, hands-free, and if it is part of the voice alarm it is monitored and battery-backed. Its limit is noise: a loudspeaker in a kitchen at full service has to be sited and set for that room, and if the room is loud enough that speech cannot be followed, the honest fix for that room is a visual indicator or a radio, not a bigger loudspeaker.

2. Closed radio. Named in the guidance (para 7.48). Two-way, which nothing else on this list is, so the control room learns that the door is locked. Its limit is the handset: who holds it on a Tuesday evening shift, whether it is charged, whether the channel is clear. A radio procedure that works is written down to the level of "the radio lives on the hook by the pass".

3. Phones and messaging. Useful as a second channel. In a basement plant room there may be no signal; in a kitchen the phone is in a locker. The guidance's test is whether the information "will reach them effectively in those areas" (para 7.49), and for phones the answer varies room by room.

4. Word of mouth. Word of mouth works when one calm person knows where everyone is. It degrades quickly with building size, background noise and stress. If it is your method, it needs to be a written procedure with named roles and a walk-through, not an assumption.

Many venues end up with the first or second as the primary channel and one of the others as the fallback. The guidance does not rank them. It asks you to choose, write it down, and test it (paras 7.28 and 7.48).

A walk you can do this month

1. List every back-of-house space where a member of staff could be alone or at work: kitchen, pot wash, stores, plant rooms, loading bay, offices, changing rooms, the cash office.
2. At peak noise, out of public hours if the test uses the sound system, have a colleague send the lockdown instruction by the method you intend to rely on.
3. In each room, record three things: was it heard, was it understood as an instruction rather than a noise, and did the person know what to do next.
4. Record who did not receive it, and why. That record is the beginning of the written procedure the guidance calls good practice (para 7.8), and it is the list of what to fix.

Procedures that are never rehearsed fail on the day. Out-of-hours testing keeps visitors undisturbed and can sit inside an existing maintenance regime.

Where a specialist helps

If the walk comes back with rooms where the message was not heard, or nobody can say which zone covers the kitchen, a communication assessment does the walk with the system's documents in hand: whether the existing public address (PA) or voice alarm can deliver distinct, zoned evacuation, invacuation and lockdown messages to every area, including back of house, and what to fix if it cannot. The fix might be a zone change, three loudspeakers in a staff corridor, or a radio for the one room no loudspeaker will serve. The report says which.

Ask about a communication assessment

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Frequently asked questions

Can our voice alarm send a message to staff areas only?
Only if the staff areas are on their own zone or zones. If the kitchen shares a zone with the restaurant, any message to one goes to both. The zone schedule in the commissioning documents shows how the building is divided; if it does not match the procedures, changing it is a modification to the system that BS 5839-8:2023 recommends is tested and certificated (Clause 41.3).

Do radios count as a communication procedure under Martyn's Law?
Yes. The Home Office guidance names "closed radio systems" among the ways of sharing information quickly at larger premises (para 7.48). The procedure needs to say who carries a radio on each shift, where it is kept, and what the fallback is if it is not answered.

Should back-of-house staff hear the same message as visitors?
Not necessarily. The guidance says the information for staff and for the public "might differ" (para 7.48). A public message says what to do; a staff message says what to do and which door to lock. Separate zones make the two possible at the same time.

Do back-of-house staff need Martyn's Law training?
There is no statutory training requirement in the Act (para 7.51), and paid third-party training is not mandatory (para 7.55). Staff with a role in a procedure must be made aware of it and of their role (para 7.51). The guidance lists team briefings, induction sessions and supervised practice among the ways to do it, and suggests a prompt card staff can carry (paras 7.53 and 7.58).

Where this comes from

Quotations from the Act and the Home Office statutory guidance are Crown copyright, reproduced under the Open Government Licence v3.0.

This page is a plain-English guide, not legal advice. Only the Security Industry Authority can determine compliance.