A sterile field encroachment indicator apparatus for a surgical lighting system includes one or more encroachment indicators, one or more sensor units, and one or more controllers. The encroachment indicators are configured to indicate encroachment of a predetermined proximity to a surgical lighthead by a foreign entity and contact of the encroaching foreign entity with the surgical lighthead. The surgical lighthead is configured to provide illumination in order to illuminate a surgical environment. The sensor units are positioned in the surgical lighthead, and are configured to sense proximity of the foreign entity to the surgical lighthead and the contact of the encroaching foreign entity with the surgical lighthead. The controllers are configured to control the encroachment indicators based on the sensed proximity of the foreign entity to the surgical lighthead and the sensed contact of the foreign entity with the surgical lighthead.