A deodorising device 10 for deodorising air； the device comprising: a housing defining an inlet chamber 22； an ozone generator 26 in fluid flow communication with the inlet chamber 22: and an electrostatic filter (50) arrangement downstream of the inlet chamber； wherein the ozone generator and filter are configured such that, in operation, the filter reduces the ozone concentration in the air from more than 0.1 ppm entering the filter to 0.1 ppm or less exiting the filter. The device may further comprise optional features such as a fan 28 , internal or external ozone concentration sensors and filter maintenance sensors. The device may further comprise an outlet chamber 24, optionally arranged vertically to or above the inlet chamber. The device may further comprise a lid (21), which optionally includes an interlock to disable the device if the lid or filter is removed. The ozone generator may be a corona discharge generator.
