This entry in the Emergency Workers series gives readers a peek into the usually hidden world of hazmat technicians. Even adults might find themselves learning from this book about the nine types of hazmats, why they are hazardous, and how technicians work with them. Ollhoff outlines the training, processes, and operations of these emergency professionals, illustrating the explanations with plenty of examples. He even includes an interview with an actual firefighter and hazmat technician. . . .There is plenty of appropriate material here paired with large, colorful photos of people in hazmat gear and within high-tech control rooms. A glossary meanwhile helps with such words as decontaminate and Geiger counter.