The present invention relates to a method for purification of air, comprising the degradation of all or some of the pollutants by the action of UV rays that are obtained by means of a single light source emitting rays at 254 nm and rays at 185 nm, and optionally UVA rays, and by photocatalysis, the ratio of the amount of energy 185 to the amount of energy 254 ranging from 0.01 to 1. The present invention also relates to a device allowing said method to be carried out.