An example luminaire includes a white light source (e.g. LEDs emitting white light in a region of the CIE color chart within three Macadam ellipses below the black body curve) and a violet light source emitting light in a wavelength range of approximately 380 nm to 450 nm (e.g. 405 nm LEDs) for deactivating bacteria, such as Methicillin-Resistant Staphylococcus Aureus (MRSA) on a surface exposed to illumination from the luminaire. A controller coupled to the sources pulses the violet light source at periodic intervals or at random times. When ON, the violet source emits light for deactivating bacteria at an intensity higher than the concurrent intensity of the white light.
