Maintenance · Guide

Changing voice alarm maintainer? The drawings were never theirs to hand over

What British Standard BS 5839-8:2023 recommends the new firm checks first, and which documents the outgoing firm actually owes you.

By Nigel Williams · Published 16 October 2026

When you sell a car, the garage that serviced it does not hand over the factory's engine drawings. It hands over the service book. Nobody expects the garage to have drawn the engine, and nobody thinks less of it for not having the drawings.

A voice alarm system works the same way. Most people only find out on the day they change maintainer.

The first visit is not a normal service

When a new firm takes over the maintenance of a Public Address Voice Alarm (PAVA) system, the code of practice recommends a special inspection before routine servicing begins (BS 5839-8:2023, Clause 41.1). The new maintainer looks at the existing system and its records, and produces a maintenance plan from what it finds.

The inspection is not open-ended. Clause 41.1 names seven areas where any non-conformity should be documented and reported to premises management:

• audibility of the alarm signals (Clause 19)
• speech intelligibility, against the objective criteria (Clause 20.3)
• standby power, including the batteries (Clause 25.3)
• fire resistance of the cables (Clause 26)
• fault monitoring (Clause 10.1)
• electrical safety (Clause 30)
• a logbook, provided where none exists

The note to the clause adds something easy to miss. Not every non-conformity has to be put right. That is your decision, made on the maintainer's advice (Clause 41.1, Note).

Why your old maintainer may never have checked

This surprises people. A system serviced faithfully for ten years can still have a design fault nobody has reported.

The commentary to Clause 40 explains why. Routine servicing confirms that the existing system still works. It is not a fresh review of the design, so a non-conformity with the design clauses will not necessarily be found at a service visit. Where a maintainer does point one out, that cannot be taken to mean the design has been reviewed (BS 5839-8:2023, Clause 40, commentary).

Commentary is guidance rather than a numbered recommendation. But the point is plain. Six-monthly and annual servicing (Clauses 40.1 and 40.2) keeps the system at the performance it was handed over with. The 41.1 inspection is the one point where the standard expects a maintainer to look back at the design, and only across those seven areas.

So who does owe you the drawings?

Here is the question that tends to land on the new maintainer's desk in the first week. "Can you send us the zone plan, the as-fitted drawings and the commissioning records?"

The standard places each of those with the organisation responsible for that stage of the work:

• As-fitted drawings: the installer, delivered to the purchaser or user (Clauses 31.11 and 35 c)).
• Design, installation and commissioning certificates: each responsible organisation, to the purchaser or user (Clause 36.1).
• A displayed evacuation zone plan: checked by the commissioning organisation at commissioning (Clause 34.3 h)).
• Acceptance: the purchaser confirms that the drawings, operating and maintenance (O&M) manual, certificates and logbook were handed over before signing acceptance (Clause 37.2 g)).

Who keeps the set afterwards? Premises management. The code recommends one named person to supervise the system, who normally holds these records and updates the drawings when the system changes (Clause 42, and 42 f)).

The maintainer is not in that chain. A maintainer appointed after handover was never party to how those responsibilities were split, because that split is agreed before the order is placed (Clause 35, commentary).

What the outgoing firm does owe you

Your contract with the outgoing firm sets most of this, so read it first. The standard's part is narrower than people expect, and it is mostly already on your premises:

• its entries in the logbook you hold on site: test results, faults and maintenance work (Clauses 39.6, 40.3 and 43.1)
• an inspection and servicing certificate for each completed service (Clause 40.4)
• a report of defects still outstanding (Clause 40.3)
• a modification certificate for any modification it carried out, with the drawings updated (Clause 41.3 d) and e))

Before the notice period ends, we recommend asking for four things in writing: the last two servicing certificates, the current list of outstanding defects, any modification certificates, and a copy of the current system configuration with the access credentials. The first three are the standard's records. The fourth is practical: without it, your new maintainer may struggle to restore the system after a controller failure.

"Isn't a takeover inspection just the new firm finding work?"

It is a fair suspicion. A firm paid to find faults, then paid again to fix them, has an obvious incentive.

Two things answer it. The scope is set by the standard, not by the maintainer: seven named areas, listed above. And the inspection and any remedial work can be priced separately, so the technician who finds a fault does not price the fix. ProAudium quotes that way as a matter of course. You then decide what gets rectified, which is exactly what the note to Clause 41.1 says.

Two examples

The missing zone plan. Picture a new maintainer asked, in week one, to produce a zone schedule for a shopping centre. If the drawings were handed over at acceptance (Clause 37.2 g)), they are with premises management. If they were not, the gap belongs to the original handover, and a zone-by-zone survey is a separately scoped job, not part of servicing.

The battery nobody resized. A 41.1 inspection covers standby power (Clause 25.3). If loudspeakers have been added over the years without a modification certificate, the batteries may no longer match the load. Routine servicing checks the batteries are healthy. It does not recalculate whether they are big enough for a load that has grown. The takeover inspection is where that question gets asked.

In short

• The new maintainer's first job is a 41.1 inspection: seven named areas, reported to you, with you deciding what to fix.
• Routine servicing was never a design review, so a clean service history does not prove a sound design.
• Drawings, certificates and the zone plan come from the installer and commissioning organisation, and premises management keeps them.
• The outgoing firm's records are its logbook entries, its servicing certificates, its defect report and any modification certificates.

The garage hands over the service book. The engine drawings were always yours to keep.

Next step. If you are changing maintainer in the next six months, find your acceptance pack and check it against the four handover items above before the old contract ends. If it is incomplete, ask the original installer first. ProAudium carries out Clause 41.1 takeover inspections across London and the South East, with any remedial work quoted separately: contactus@proaudium.com or 01273 034630.