A safety device for an aerial lift includes a basket with controls which permit an operator standing in the basket to maneuver the basket. The safety device includes an alarm, a switch activation device proximate to the controls and two solenoid operated relays, one connected with a normally-closed manually operable emergency switch which is operable to cut electrical supply and prevent further movement of the basket, and one connected with a foot operable safety switch, which must be held closed by an operator to activate the controls. Each relay is held in a closed condition unless caused to change to an open condition to cut electrical supply. The relays are controlled by a programmable control box connected to the switch activation device, foot switch and alarm. The control box causes the alarm to operate in accordance with the condition of the foot operable safety switch.