The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.
How we test grease extraction
We turn the cooker hood onto maximum setting, then drip a small amount of oil and water onto a hot pan for 30 minutes. We then leave the cooker hood on for a further 10 minutes and record how much grease has been captured by the filter.
How we test odour extraction
We turn on the cooker hood to its maximum setting, then fill a pan with water and heat it up on the hob. A strongly aromatic chemical (methyl-ethyl ketone) is dripped into the water over 30 minutes. Its aromatic concentration is measured every minute at four different points in the room to determine how effective the cooker hood is at extracting the smell.
How we test steam extraction
We heat up a pan of water on each cooking zone of a hob. When the humidity has reached 90%, we turn on the extractor fan to maximum and record how long it takes for the humidity to drop to 60%. This gives a good indication of how effective the cooker hood is at removing steam.
How we test noise
We turn the cooker hood on to maximum then measure the noise at a distance of one metre. A panel of assessors also note any specific noises such as vibration, humming or rattling.
How we test ease of use
We assess how easy it is to install, use, clean and maintain the hood, including the quality of the lighting.
