A fire suppression system for anechoic chambers with multiple non-retractable tubes fixed on the ceiling of the chamber, with each tube connected to a pneumatic valve. Each valve is controlled by a compressed air supply that reacts to the presence of fire in the chamber. Once fire is detected in the chamber, the valves vent the compressed air to permit fire retardant fluid to pass through the fixed tubes into the chamber. The tubes and the valves do not interfere with the functions of the chamber and provide immediate fire suppression.