Direct answer

Disablement (isolation) temporarily takes part of a fire alarm system out of service — for example a detector, a zone, or the sounders — usually during building work, cleaning or hot work that would otherwise cause a false alarm. As general guidance, only disable the minimum necessary, for the shortest time, with the responsible person's authorisation and suitable alternative fire precautions in place, record it in the log book, and reinstate and test it as soon as the work is finished. The exact key sequence or menu steps to disable and reinstate are specific to the panel model; refer to the manual for your specific Hochiki panel.

Applies to

Products / Models: Hochiki Europe control panels (general guidance — see your panel manual for the exact procedure)
Firmware / Version: Not applicable
Region: UK / Europe
Standards: BS 5839-1 (disablements)

What disablement is and when it is used

Disablement (also called isolation) temporarily stops part of the system from generating or acting on a signal — for example isolating a detector before dusty work, or disabling sounders during testing.
It is a controlled, temporary measure — not a way to silence a recurring problem. A persistent fault or false alarm should be investigated, not left disabled — see Why is my fire alarm panel showing a fault or beeping? and How to reduce false alarms (unwanted fire signals)?.

Before you disable anything

Get authorisation from the responsible person for the premises.
Disable only the minimum part needed (one detector or zone rather than the whole system where possible) and for the shortest time.
Put suitable alternative fire precautions in place for the affected area while it is disabled (for example a fire watch), as advised by the responsible person or a competent person.

Steps (general procedure)

Confirm authorisation and scope
- Agree with the responsible person exactly what will be disabled, why, and for how long.
Identify the device, zone or output to isolate
- Use the panel to identify the specific detector, zone or sounder circuit affected.
Disable using the panel's documented procedure
- Follow the disable/isolate function in the manual for your specific Hochiki panel. Confirm the panel shows the disabled condition.
Record the disablement in the log book
- Record what was disabled, the date and time, who authorised it, and the reason — see What should be recorded in the fire alarm log book?.
Reinstate as soon as the work is complete
- Re-enable the device, zone or output following the panel's documented procedure and confirm the disabled indication has cleared.
Test and log the reinstatement
- Confirm the reinstated part operates normally and record the reinstatement (date, time, who) in the log book.

What to record in the log book

What was disabled and why, who authorised it, and the date/time disabled.
The date/time reinstated and confirmation it was tested as working.

When to contact technical support

If you are unsure how to disable or reinstate a specific Hochiki panel safely.
If part of the system has been left disabled and you are not sure how to reinstate it, or the disabled indication will not clear after reinstatement.

Safety note

This article is general guidance for Hochiki Europe products. Installation, commissioning, maintenance and modification of fire detection and alarm systems must be carried out by a competent person in accordance with the applicable standards (for example BS 5839-1 in the UK) and the requirements of the relevant authority having jurisdiction. Always refer to the current product manual and data sheet for the exact model before carrying out any work.

References

BS 5839-1 (current edition) — disablements and reinstatement recommendations
The manual for your specific Hochiki control panel (disable / isolate procedure)
System log book

Last reviewed: 2026-06-16 — Reviewed by: Takashi Ishikawa

How to disable part of a fire alarm system safely