Please remember that a cooker hood is a domestic appliance used for extracting all odours, smoke and grease particles produced while cooking in the kitchen. Possibly this hood will be connected to an existing trunking to outside. Also the minimum distances from the cooker top (height and width) must be maintained to achieve the proper safe and optimized hood performance. Failure to take these parameters into account will create a deficient, or even void, effectiveness of extraction. Before choosing your cooker hood you should evaluate your kitchen dimensions as well as the appliances involved. Care should also be taken as to the correct connections to any reused existing ducts, as explained later.