A multi-stage fire suppression system according to various aspects of the present invention is configured to deliver a fire suppressant material in response to multiple detections of a fire condition over time. In one embodiment, the multi-stage fire suppression system comprises at least two pressure tubes each having a different internal pressure. Each pressure tube is adapted to generate a pneumatic signal in response to exposure to a different trigger event. The pneumatic signal is used to activate a suppression system and release the fire suppressant material from a container. The multi-stage fire suppression system may also be configured to signal a secondary hazard detection system that a fire has been detected.