An elevator safety system comprising: a speed detector configured to sense a speed of an elevator system mass; an acceleration detector configured to sense an acceleration of the mass; a mechanical safety configured to be connected to the elevator system mass; an electromagnetic trigger (46; 86) connected to the mechanical safety (24; 70A, 70B); and a controller configured to release the trigger (46; 86) to engage the mechanical safety when (a) the speed detector senses an over-speed condition or (b) the acceleration detector senses an over-acceleration condition for the mass, and to automatically reset the trigger (46; 86); characterised in that: the electromagnetic trigger (46; 86) comprises a link (72; 92), a linear actuator (74; 94), an electromagnet (76; 96) and a spring (78; 98); the link (72; 92) is kinematically connected to the mechanical safety (70A, 70B); the linear actuator (74; 94) is connected to one side of the elevator system mass; the spring (78; 98) is connected between the link (72; 92) and elevator system mass; the electromagnet (76; 96) is connected to the linear actuator (74; 94); when the electromagnetic trigger (46; 86) is in a ready state, the spring (78; 98) is compressed and the electromagnet (76; 96) is magnetically connected to the link (72; 92); and when the electromagnetic trigger (46; 86) is released, the spring (78; 98) is decompressed and the electromagnet (76; 96) is actuated so that the link (72; 92) is allowed to move away from the electromagnet (76; 96). a speed detector configured to sense a speed of an elevator system mass; an acceleration detector configured to sense an acceleration of the mass; a mechanical safety configured to be connected to the elevator system mass; an electromagnetic trigger (46; 86) connected to the mechanical safety (24; 70A, 70B); and a controller configured to release the trigger (46; 86) to engage the mechanical safety when (a) the speed detector senses an over-speed condition or (b) the acceleration detector senses an over-acceleration condition for the mass, and to automatically reset the trigger (46; 86); characterised in that: the electromagnetic trigger (46; 86) comprises a link (72; 92), a linear actuator (74; 94), an electromagnet (76; 96) and a spring (78; 98); the link (72; 92) is kinematically connected to the mechanical safety (70A, 70B); the linear actuator (74; 94) is connected to one side of the elevator system mass; the spring (78; 98) is connected between the link (72; 92) and elevator system mass; the electromagnet (76; 96) is connected to the linear actuator (74; 94); when the electromagnetic trigger (46; 86) is in a ready state, the spring (78; 98) is compressed and the electromagnet (76; 96) is magnetically connected to the link (72; 92); and when the electromagnetic trigger (46; 86) is released, the spring (78; 98) is decompressed and the electromagnet (76; 96) is actuated so that the link (72; 92) is allowed to move away from the electromagnet (76; 96). the electromagnetic trigger (46; 86) comprises a link (72; 92), a linear actuator (74; 94), an electromagnet (76; 96) and a spring (78; 98); the link (72; 92) is kinematically connected to the mechanical safety (70A, 70B); the linear actuator (74; 94) is connected to one side of the elevator system mass; the spring (78; 98) is connected between the link (72; 92) and elevator system mass; the electromagnet (76; 96) is connected to the linear actuator (74; 94); when the electromagnetic trigger (46; 86) is in a ready state, the spring (78; 98) is compressed and the electromagnet (76; 96) is magnetically connected to the link (72; 92); and when the electromagnetic trigger (46; 86) is released, the spring (78; 98) is decompressed and the electromagnet (76; 96) is actuated so that the link (72; 92) is allowed to move away from the electromagnet (76; 96).