The kitchen extract system presents particular hazards due to the potential for the accumulation of grease. Whilst general cleaning of the Canopies or cooking stations may be carried out on a regular basis, the majority of the extract system itself requires a professional team to ensure it is running at its full potential.
As grease accumulates within the extract system, the effectiveness of the extract system is reduced, but also, accumulated grease within an extract system forms a hidden combustion load.
Under certain circumstances, flame or very high temperature within the duct can ignite the grease causing fire to spread rapidly through the duct.
Kitchen extract ventilation systems are defined within HVCA guidelines (TR/19), as extract systems intended to collect and remove contaminants, heat and moisture from cooking appliances. A kitchen extract system would typically comprise of the following components:
Canopy � also referred to as hood, canopy hood, extraction hood, cooking hood, cooker hood, cooking canopy or extraction canopy.
Ducting �beyond the canopy, extraction ductwork would be connected. This may involve short transition ducts connected directly to the suction side of an extract fan or could include many linear metres of horizontal and or vertical ductwork. Vertical ductwork, also referred to as riser, may pass through many levels of a building. Contained within the ducting there may be attenuators, flow control dampers, fire dampers, air turning vanes and sensors.
Extract fan � to create extraction from the canopy an extract fan would be connected to the ductwork, some extract fans (usually roof mounted) discharge directly to atmosphere via a cowl.
Discharge Duct � on the exhaust side of the fan, a discharge duct would direct extract air out of the building via an outlet. This outlet point may include weather louvres and mesh to prevent the ingress of weather and vermin. Other systems such as ventilated ceilings and directly ducted extraction are also used. It is important that the person responsible for implementing cleaning regimes clearly understands the breakdown of the system so that any cleaning regime is compliant with the terms of buildings insurance relevant to the kitchen extract maintenance.
Password Services provide a Duct Cleaning service that will ensure all aspects of the Extract System is contaminate free, but one that fits in and around the working hours of the kitchen. This usually involves the cleaning taking place during the night when the kitchen is closed, therefore not affecting the business.
A detailed report is provided following the clean, which will highlight any additional work required, to ensure that the Extract System complies with HVCA DW/172 in regards to design and access.