Abstract: A pneumatic release system has an inlet arranged to be connected, in use, to a supply of pressurised fluid, and an outlet arranged, to be connected, in use, to an end device. The system defines therethrough, a flow path for fluid from the inlet to the outlet. The system includes a piston mounted in and axially moveable relative to a cylinder, the inlet and outlet defined in the cylinder. The piston has a piston end on which are mounted upper and lower seals and is biased to a first closed position, in which the upper and lower seals define a chamber within the cylinder to retain pressurised fluid from the inlet, the upper seals preventing flow of the fluid from the chamber to the outlet, and wherein an external force applied to the piston moves the upper seals away from sealing engagement with the cylinder.

Abstract: An emergency actuation device for opening a door, the emergency actuation device includes: at least one pressurised gas supply; an actuator including: an actuator chamber, an actuator piston moveable between a retracted position and a fully extended position to open the door, a vent for venting the actuator chamber when the actuator piston is in its extended position. The emergency actuation device further includes a percussion device including a percussion piston moveable on activation of the percussion device between: a storage position in which the pressurised gas supply is isolated from the actuator and an activated position in which the pressurised gas supply is coupled to the actuator. The actuator is coupled to the percussion device; and the actuator is configured such that movement of the actuator piston towards its activated position resets the percussion piston.