This text covers basic chemistry for emergency responders, guiding students who are often non-science majors through the process of understanding the chemical properties that make materials hazardous.
You'll find this one to be a bit less expensive, compared with other references. No, it's not everything you need to know, but it's a great guide to the chemistry that emergency responders need to know, and the author doesn't assume that you have a scientific Ph.D. By Eugene Meyer.