This document discusses Blueproof, a fire suppression device that can be easily installed on radiators. It argues that Blueproof is the most cost-effective way to stop rapid fire spread in high-rise buildings. Blueproof works by using the water already in radiators, which increases in pressure when exposed to heat, to suppress fires. It has been installed thousands of times with no leaks or failures. Testing has proven it can eliminate flashover and effectively suppress fires even with exterior chimney effects.