The calm of the night is shattered by an explosion and flames: a chemical factory is on fire, and a dangerous gas is drifting across town! This book looks at the topic of chemical reactions to explain the properties of chemicals and how they react, what has caused the explosion, and how the resulting fire and pollution can be tackled. It shows how the emergency services use their knowledge of science and technology to make the factory safe, and how investigators can analyze the evidence to determine the cause of the disaster.