Restaurant Kitchen Fire Suppression — What UK Law Requires

Why kitchen suppression matters

Home Office fire statistics for England consistently place cooking appliances at the top of the ignition sources for accidental dwelling fires, and cooking is a persistent cause of fires in commercial premises. In commercial kitchens, the combination of high heat, hot oil, ventilation grease build-up and constant operation creates a Class F fire risk that hand-held extinguishers alone cannot manage.

A wet-chemical suppression system at every cooking station is the engineering control that contains a Class F fire before it spreads.

What the law and standards say

Article 13 of the Regulatory Reform (Fire Safety) Order 2005 requires premises to be equipped with "appropriate fire-fighting equipment". For Class F cooking risk, BS 5306-8:2023 — the code of practice for selecting and positioning portable extinguishers — translates that into three things:

• Wet chemical (Class F) extinguishers sized to the exposed hazard area (Table 2: a 0.5 m × 0.7 m fryer, about 0.35 m², calls for 2 × 75F), and only Class F media sited where cooking oils are the main risk (7.6.1)
• A maximum travel distance of 10 m from the hazard to the extinguisher (8.4), reduced by 5 m for every door on the way
• A fixed extinguishing system as well where the exposed Class F area exceeds 0.4 m² (7.6.1) — and, per the note to Table 2, where the range layout (a back wall, a tunnel canopy) restricts access for a hand-held extinguisher

BS 9999:2017 treats a cooking range in a catering area as a localised area of high fire risk; an effective localised suppression system (Clause 38) lets that risk profile be treated as medium rather than high (Table 3, Note 3). Some insurers make fixed suppression a condition of cover where deep-fat fryers are present — check the policy wording.

How a kitchen suppression system works

A typical wet-chemical canopy system:

• Nozzles positioned over each cooking appliance
• Detection via fusible link in the canopy
• Activation triggers manual or automatic discharge
• Discharge floods the canopy and cooking surfaces with wet chemical
• Gas supply is automatically isolated
• Ventilation is shut down (typically)

Discharge time and nozzle coverage are set by the manufacturer's datasheet and the system's approval listing — not something to assume from one installation to the next.

Servicing requirements

The service regime comes from the manufacturer's instructions and the system's third-party approval listing (LPCB LPS 1223 where the system is LPCB-approved). Typically:

• 6-monthly — Inspection and functional test of detection, gas isolation and manual operation, by a competent engineer trained on that system
• Longer-cycle overhaul — Agent replacement and cylinder testing at the interval the manufacturer specifies

The 6-monthly visit is more frequent than most building-management cycles, so it is often missed.

Ductwork cleaning

A suppression system protects the cooking surface — it does not address grease build-up in the extract ductwork. BESA's TR19 Grease (the document BS 9999 points to for kitchen extract systems) sets typical cleaning intervals by hours of cooking per day:

• Heavy use (12–16 hours/day): every 3 months
• Moderate use (6–12 hours/day): every 6 months
• Light use (2–6 hours/day): every 12 months

Insurers often demand TR19 evidence at renewal.

Common findings

• Suppression installed at fit-out and never serviced since
• Manual pull station blocked by equipment
• Detection fusible link painted over
• Nozzles repositioned during kitchen refurb without re-commissioning
• Ductwork uncleaned beyond TR19 cadence

The combined regime

A defensible kitchen fire safety regime includes:

• Wet-chemical suppression system, 6-monthly serviced
• Class F extinguisher within reach
• Trained kitchen staff (basic suppression awareness)
• TR19-compliant duct cleaning records
• Fire risk assessment specifically addressing kitchen risk

MetroFire delivers wet-chemical suppression install and 6-monthly servicing for restaurants, hotels and HMOs across London and the South East. Book.