Kitchen Extract Cleaning and Monitoring


Your responsibility

The Health & Safety Executive, industry and insurance guidance and regulations stipulate that kitchen extract systems should be kept clean to minimise fire and other risks, the B&ES association document TR19 ‘Cleanliness of Ventilation Systems’ provides specific guidance on methods of measuring and defining cleanliness as a bench mark for good practice.

It is your responsibility to ensure that kitchen grease extract systems (canopies, filters, ductwork, risers and fans) in all commercial kitchens and the like are inspected as required by your buildings insurance policy, in accordance with Fire Safety and Workplace (Health, Safety & Welfare) Regulations.

An important factor of the rate at which combustible grease accumulates on the internal surfaces of a kitchen extract system is the effectiveness of the grease filters fitted in the canopy. They should be regularly cleaned and inspected and checked for fit. Any grease laden air able to bypass the filter and enter the extract system has serious implications as to the amount of contamination able to accumulate on internal kitchen extract duct surfaces.

Grease is a combustible and B&ES TR19 provides a method of measuring and defining cleanliness and dirtiness recommending a Wet Film Thickness Test (W.F.T.T) to determine the level of grease contamination and recommend any remedial actions based on these measurements.


How often should kitchen extracts be cleaned?

Table 11: Frequency of Cleaning (B&ES TR19)

Heavy Use   12-16 Hours per Day 3 Monthly
Moderate Use 6-12 Hours per Day 6 Monthly
Light Use   2-6 Hours per Day   12 Monthly


Building managers are required to:

  • Identify and assess the sources of risk

  • Prepare a scheme for preventing or controlling the risk

  • Appoint a person to be managerially responsible

  • Implement and manage precautions

  • Keep records of the precautions implemented