Abstract: An apparatus includes an electrical power source and a solid-state circuit located within a housing. The circuit is coupled to the electrical power source such that circuit is initially in an inactive state in which electrical current is prevented from flowing through the solid-state circuit, the inactive state corresponding to an OFF mode of the apparatus. The circuit further includes an active state in which electrical current is allowed to flow through the solid-state circuit, thereby turning the apparatus in an ON mode, the active state being triggered by a momentary voltage and remaining active after the momentary voltage is removed.

Abstract: A fume hood having a retrofit drive assembly includes an elongated lifting piece, such as a toothed rack, which attaches to a fume hood sash at connection point that minimizes stress on the sash. The retrofit drive assembly also includes a drive motor driven rotary engagement member, such as pinion, for opening and closing the sash. This arrangement allows for easy field retrofit, and requires limited intrusion from behind the upper regions of the existing fume hood.

Abstract: A fume hood comprised of first and second side walls, a back wall, a work surface, and a top wall, the walls and work surface defining a work area, an access opening for providing a user access to the work area, a movable sash member disposed for vertical movement across the access opening, and an anti-cocking drive mechanism mechanically coupling a drive motor to the movable sash member.

Abstract: A fume hood comprised of first and second side walls, a back wall, a work surface, and a top wall, the walls and work surface defining a work area, an access opening for providing a user access to the work area, a movable sash member disposed for vertical movement across the access opening, and an anti-cocking drive mechanism mechanically coupling a drive motor to the movable sash member.