Abstract: A luminaire includes a housing and a light engine. The light engine is detachably secured to the housing and includes a lens and an optical tray. The lens has a top surface, a bottom surface, and a peripheral edge. The top surface of the lens define a lens cavity. The optical tray is supported by the lens within the lens cavity.

Abstract: A luminaire includes a housing and a light engine. The light engine is detachably secured to the housing and includes a lens and an optical tray. The lens has a top surface, a bottom surface, and a peripheral edge. The top surface of the lens define a lens cavity. The optical tray is supported by the lens within the lens cavity.

Abstract: A lamp assembly adjustable between narrow beam and wide beam light distributions, the lamp assembly is particularly intended for housing lamping or the like for mounting to industrial emergency unit fixtures of differing size and conformation. At least one and preferably two of the lamp assemblies are mounted to a unit fixture in spaced relation to illuminate critical areas within an industrial or commercial space during emergency conditions, such as failure of mains power, to allow evacuation of the space. In order to illuminate the desired areas, each of the lamp assemblies can be adjusted along an internal track to allow light to be directed toward a particular location within a wide range of possible locations, thereby facilitating illumination of the most desirable area in the vicinity of the unit fixture for a particular mounting location. Additional flexibility in the delivery of illumination to a desired area is provided by adjustability between narrow and wide beams.