Martyn's Law: Terrorism Protection of Premises
Not every new law that touches the premises engineers work in is about fire. Martyn's Law — the Terrorism (Protection of Premises) Act 2025 — is about preparedness for terrorist attacks, requiring certain public premises and events to be ready to keep people safe. It sits on the security side of "fire and security," distinct from fire safety law, but it affects the venues and clients that security-aware engineers deal with. Understanding the essentials helps an engineer have sensible conversations about it. This guide gives an orientation.
The central point is that Martyn's Law requires certain public premises and events to be better prepared for terrorist attacks, through a tiered, capacity-based regime — security legislation distinct from fire safety law.
Who this is for
This is for fire and security engineers who want to understand a significant piece of security legislation affecting the premises they and their clients work in. The experience level assumed is competent engineer. Use this as orientation; the duties rest with those responsible for qualifying premises, and the authoritative source is the Act and its statutory guidance. It is distinct from fire safety law, which continues to follow the Fire Safety Order and BS 5839-1 for fire alarms.
What Martyn's Law is
Martyn's Law is the common name for the Terrorism (Protection of Premises) Act 2025, which received Royal Assent in April 2025. It requires certain public premises and events to be better prepared to keep people safe in the event of a terrorist attack. It introduces duties on those responsible for qualifying premises, with a tiered approach based on capacity, and establishes the Security Industry Authority as the regulator. It is security legislation, distinct from fire safety law, and it does not change how a fire alarm is designed. The authoritative source is the Act and its statutory guidance, which should be consulted directly for the detail rather than a summary.
The tiered approach
The Act uses a tiered approach based on how many people premises or events can host. Broadly, a standard tier applies to premises hosting from 200 up to 799 people, focused on simple, low-cost preparedness activities to help those working there reduce harm in an attack, and an enhanced tier applies to premises and events hosting 800 or more, with additional requirements to consider appropriate and reasonably practicable public protection measures. The tiers scale the expectations to the scale of the premises. The precise thresholds and duties are set out in the Act and its statutory guidance, which should be consulted directly. Understanding which tier a premises falls into is the starting point for its obligations.
Implementation and the regulator
Like much major legislation, Martyn's Law has an implementation period after Royal Assent before the requirements come into force, intended to give those in scope time to prepare, with the requirements expected to commence after that period. The Security Industry Authority is established as the regulator for the regime, overseeing compliance. Because the exact timing and detailed duties are set by the Government through commencement arrangements and statutory guidance, they should be confirmed against those authoritative sources rather than a summary. For an engineer, the practical point is that this is coming, with time to prepare, and clients in scope will need to act.
Relevance to fire and security engineers
For engineers, Martyn's Law is context rather than a change to technical fire alarm work. It is terrorism-protection legislation, not fire safety, so it does not alter fire alarm design; but it affects the premises and events that security-aware engineers and their clients work in, and it sits alongside fire and security systems in a premises' overall safety and preparedness. From field experience, being able to talk sensibly with a client about their emerging obligations — while being clear it is a security-preparedness matter for the responsible person, not a fire alarm design issue — is genuinely useful. The duties rest with those responsible for qualifying premises; verify specifics against the Act and statutory guidance.
Common points to check
For engineers, the practical points are recognising that Martyn's Law is distinct from fire safety, knowing which tier a client's premises might fall into, and directing clients to the Act and statutory guidance for their duties. Confirming the distinction from fire safety and pointing to authoritative sources is the essential contribution.
When not to rely on this alone
When not to use this article: do not treat it as a statement of a premises' specific duties under Martyn's Law. Those come from the Act and its statutory guidance, applied by those responsible for the premises; where duties are in question, appropriate advice should be taken.
Relevant law and guidance
Martyn's Law is the Terrorism (Protection of Premises) Act 2025, security legislation with statutory guidance and the Security Industry Authority as regulator — distinct from fire safety law and from BS 5839-1 for fire alarms. Verify specific duties against the Act and its statutory guidance, and always work to current guidance.
Professional disclaimer
This is an educational and workflow resource for competent engineers and does not replace the Act, its statutory guidance, legal advice, or competent judgement. It is orientation only; verify specific duties against the authoritative sources.
Related documentation
Use this with the Terrorism (Protection of Premises) Act 2025 and its statutory guidance, and the ProtectUK resources. Keep it distinct from fire safety work, and direct clients' premises duties to the authoritative sources.