Abstract: A method of operating an incursion warning system for a work zone, the incursion warning system comprising: a plurality of sensor units arranged about a perimeter of the work zone; and a plurality of alarm units each comprising one or more of an audio, visual or haptic alarm operable to warn a workforce of a potential danger in response to a detected breach into the work area; the method comprising: establishing a geo-zone delimiting a geographical area that includes at least part of the work zone; and a set of rules associated with the geo-zone; deriving an instruction for one of the alarm units determined to be in the geo-zone from the set of rules based on a characteristic of the alarm unit and a characteristic(s) of one or more other alarm units determined to be within the geo-zone; and wherein the instruction is derived in response to a change in a characteristic of the alarm unit and/or the one or more other alarm units and/or one or more of the sensor units within the geo-zone.
Abstract: A system in which a sensor unit in the casing of a lantern detects an impact and generates a wireless alert signal and is powered from the battery used to power the light source of the lantern. The sensor unit can be mounted onto the terminals of a battery and held within the cavity of the lantern housing used to house the battery. In this way the sensor unit can be incorporated with the lantern without any modification to the design of the lantern.