Standards
Standards, in our own words
Voice alarm has its own family of standards. BS 5839-8:2023 covers voice alarm systems that broadcast in response to fire detection; BS 7827:2019 covers emergency sound at sports grounds, large public buildings and venues; BS EN 50849:2017 covers sound systems for emergency purposes that are not part of a fire evacuation; and the Terrorism (Protection of Premises) Act 2025 requires qualifying premises to have public protection procedures, one of which is communicating with people on the premises. The pages below explain the clauses that ProAudium's articles and tools rely on, in plain English, with the clause numbers.
These are our explanations, in our own words, of the clauses our articles rely on. We do not reproduce the standard's text: the clause numbers are there so you can check each one against your own copy. They support the published standard and the judgement of a competent technician, and replace neither.
Reviewed on 1 October 2026 by Nigel Williams.
The standards
BS 5839-8:2023: voice alarm systems
Emergency messages, standby batteries, the Annex C battery calculation, and how often a voice alarm should be tested and serviced.
BS 7827:2019: emergency sound systems at sports grounds and large venues
Which standard each zone of a large venue follows, back-up power and the sports-ground duty cycle, fault reporting and acceptance.
Terrorism (Protection of Premises) Act 2025 (Martyn's Law)
Who qualifies, the two tiers, the four procedures and notifying the Security Industry Authority (SIA). Royal Assent 3 April 2025. Status at 1 October 2026: the SIA expects commencement in spring 2027; no date has been set.
BS EN 50849:2017 and BS 5839-9 (emergency voice communication systems) are cited in the articles; each article's Where this comes from table links to BSI's page for the standard.
Which standard applies to your system?
The connection to fire detection decides, not the type of building. A system that broadcasts automatically in response to fire detection is a voice alarm under BS 5839-8:2023. A sound system for emergency purposes that is not part of the fire evacuation falls under BS EN 50849:2017, which excludes fire evacuation systems from its scope. At a stadium, arena or transport hub, BS 7827:2019 sits above both: its Clause 4.1 recommends a risk assessment that divides the venue into voice-alarm zones and emergency-sound-system zones, and each zone then follows the standard allocated to it. A stadium can therefore be either, or both, zone by zone.
Are these standards requirements?
They are codes of practice, and a code of practice recommends. A recommendation becomes binding only when a contract, a specification, a regulation or a safety-certificate condition calls it up.
What the clauses mean for a system in service
Most of what these pages are cited for happens on a service visit: the six-monthly and annual activities in BS 5839-8:2023 Clause 40, the battery clauses, the wording of the messages. What each maintenance level includes sets the three maintenance levels against those clauses, and says plainly which level meets the standard's servicing interval and which does not.