Grease vapour from cooking condenses inside the canopy, filters and ductwork. Over time the deposits build up and can ignite, and a fire inside a duct can spread quickly through a building.
What the London Fire Brigade says
The London Fire Brigade's guidance for takeaways, cafés and restaurants says kitchen ducting should be cleaned regularly to avoid a build-up of grease, which could ignite and cause smoke and fire to spread to other areas of the property and nearby premises (London Fire Brigade).
The same guidance says a solid fuel oven needs its own dedicated canopy and ventilation system, separate from other appliances, built to withstand the high temperatures from solid fuel, and that the extraction fan should keep running until all coals or wood are fully out and cold. LFB also refers businesses to its guidance note GN86 – Catering Kitchen Extract Systems.
Your legal duties
If you are responsible for business premises in England and Wales you must carry out a fire risk assessment and put fire safety measures in place (gov.uk; Regulatory Reform (Fire Safety) Order 2005). Your kitchen extract system should be part of that assessment.
Day-to-day steps
- Clean canopies, filters, drains and traps daily or weekly, as TR19 recommends alongside specialist cleaning.
- Book specialist cleans at the right interval – check yours.
- Keep cleaning records with your fire risk assessment.