The method of separating grease from air.

Grease Control.

What is Grease?

Grease in kitchen ventilation systems primarily consists of lipid-based substances such as oils and fats, which can form aerosols released into the air during cooking processes. These particles can accumulate on surfaces, posing several challenges and risks, including fire hazards and maintenance issues.

Why separate grease from extracted air

External Environment

Prevents the release of grease-laden air into the environment, which can cause pollution and unpleasant odours.

Duct Cleanliness

Accumulated grease in ducts can lead to blockages and reduce the efficiency of the ventilation system. Ensures compliance with hygiene regulations such as TR19 and insurance policies by maintaining cleaner ducts.

Fire Prevention

Grease build-up is highly flammable and can significantly increase the risk of fires within the ventilation system.

Fan Cleanliness

Keeps the fans and other components free from grease deposits, ensuring they operate efficiently and have a longer lifespan.

Methods of Separating Grease

Depending on the style of cooking and cuisine, different methods of separating grease from the air will be specified. Baffle filters are always installed in the canopy and form the first line of filtration. Some items used for grease separation also serve other purposes, such as ozone injection, which is primarily used for odour reduction and elimination.


Baffle Filters

Baffle filters force air through a series of baffles, causing grease particles to coalesce and drain into a collection trough. These filters are highly effective in trapping larger grease particles and are easy to clean.



Prefilters capture larger particles of grease and dust, providing initial filtration that extends the life of subsequent filters such as carbon, fine filters, absolute (HEPA) filters etc.


HEPA Filters

HEPA filters provide high-efficiency filtration, removing up to 99.97% of airborne particles, including very fine grease aerosols, ensuring the highest air quality. These are expensive, normally used for smoke filtration and are usually the last line of filtration for grease and or smoke that has already been removed from the air.


Inline UV Lamps

UV lamps within the ductwork use ultraviolet light to break down grease molecules into smaller, less harmful compounds. This process, known as photolysis, reduces the amount of grease that settles within the ducts.


Ozone Injection

Ozone generators inject ozone into the ductwork. Ozone is a powerful oxidizing agent that reacts with grease particles, breaking them down into less sticky substances that are easier to manage and less likely to accumulate.


ESP Units (Electrostatic Precipitators)

ESP units use an electrostatic charge to attract and capture grease particles from the airflow. These units are highly efficient in removing fine grease particles and can significantly reduce the maintenance required for ducts and fans.