Kitchen ventilation

Kitchen ventilation is the branch of ventilation that specialises in the treatment of air from kitchens.^[1] Kitchen ventilation presents the problems of grease, smoke and odours not usually found in other ventilation systems.

Restaurant kitchens often use large extractor hoods

Equipment used in kitchen ventilation uses an extractor hood or canopy and a filtering system. The fan for the ventilation system may be located within the kitchen or in the duct system nearby.

Requirements

An adequate kitchen ventilation system should achieve the following objectives:

• remove cooking fumes at the source, i.e. as close to the cooking equipment as possible
• remove excess hot air and introduce incoming cool clean air so that a comfortable environment is achieved. Inadequate ventilation can cause stress, contributing to unsafe systems of work and high staff turnover.
• ensure that the air movement in the kitchen does not cause discomfort
• provide sufficient air for complete combustion at fired appliances, and prevent the risk of carbon monoxide accumulating
• be easy to clean, avoiding the build-up of fat residues and blocked air inlets which lead to loss of efficiency and increase risk of fire
• be quiet and vibration free

Kitchen ventilation design

The main factors that need to be taken into account when designing a kitchen ventilation system are:

• workload of the kitchen
• amount, type and power of cooking equipment used
• layout and shape of the kitchen
• number of staff working in the kitchen
• the need for easy cleaning and maintenance
• energy efficiency
• some cooker hoods now use the recirculation method, which cleans the air and puts it back into the kitchen. This method is used if there is no way to push the air outside through a chimney system from the cooker canopy.

Grease filters

The most common types of grease filters used in professional kitchens are:

• Water-based
• Cyclonic
• Ultraviolet (UV)
• TurboSwing

Comfort

The general parameters of what is considered comfortable in a kitchen are:

• Temperature: 20 °C in the winter and 28 °C in the summer, with a maximum difference with the outside temperature of 6 °C
• Relative humidity: approximately 70%
• Air velocity: less than 0.5 m/s (0.3 m/s in refrigerated areas)

References