Abstract: There is provided a fan assembly comprising a motor-driven impeller arranged to generate an airflow, an air outlet arranged to emit the airflow, a plurality of sensors arranged to measure a value for each of a plurality of air quality characteristics, a display and a processor. The processor is configured to receive measured values for each of the plurality of air quality characteristics, identify one of a corresponding set of intervals within which the measured value falls and select an air quality index value associated with the identified interval. The processor is then configured to identify the highest of the selected air quality index values as a current overall air quality index value and to cause the display to display a time series plot of the current air quality index value and a number of preceding air quality index values.

Abstract: The invention relates to phosphorescent light covers (1) and coatings that, following illumination from a light source (2) will luminesce over a period of time after illumination from the light source has ceased. A phosphorescent light covering (1) or coating is adapted to be retained or located on or about a light source (2), the cover (1) or coating comprising a base material and one or more phosphorescent compounds. The cover (1) may be in the form of a sleeve (1) adapted to encompass a fluorescent globe (2), part or all of which allows light transmission, the light cover (1) further comprising friction fit end pieces (3) having an aperture or apertures (8) through which connection pins (9) may penetrate.