What are the legal requirements for duct cleaning?

The legislation that applies

• Workplace (Health, Safety and Welfare) Regulations 1992, regulation 6 — enclosed workplaces must have effective and suitable ventilation with a sufficient quantity of fresh or purified air
• Regulatory Reform (Fire Safety) Order 2005 — the responsible person must assess and reduce fire risk, which includes accumulated grease in kitchen extract systems
• Control of Substances Hazardous to Health Regulations 2002 — LEV systems must be maintained in efficient working order and thoroughly examined and tested, generally at least every fourteen months
• Health and Safety at Work etc. Act 1974 — the general duty to ensure health and safety so far as reasonably practicable
• Health Technical Memorandum 03-01 — specific ventilation requirements for healthcare premises in England

What that means in practice

None of these state a cleaning interval. They require an outcome: ventilation that works, fire risk that is controlled, exposure that is prevented. Demonstrating that outcome requires you to know the internal condition of your systems, which requires inspection, which in turn requires access.

The practical test applied after an incident is simple. Did you know the condition of the system? Did you act on what you found? Can you evidence it? A file containing dated surveys, cleaning reports with verification results and a recommended frequency answers all three.

Where insurance sits

Insurance is often the sharper constraint. Commercial policies covering premises with catering facilities routinely include conditions requiring kitchen extract systems to be cleaned to a recognised standard at a stated frequency, with evidence retained. Failure to produce that evidence at claim stage can reduce or invalidate cover.

Read the policy wording rather than assuming. Some insurers name TR19 Grease explicitly; some specify frequency by cooking hours; some require certification from a contractor holding particular accreditation.

What to keep on file

• The most recent survey or condition report for each system
• Cleaning reports including pre and post clean photographs against asset references
• Verification results, not just a statement that the system was cleaned
• Grease deposit thickness readings for kitchen extract systems
• LEV thorough examination and test reports, retained for at least five years
• A written schedule of the next planned inspection for each asset