ISO - Insurance Service Office - This is a, for profit, organization that provides statistical information on risk. For many years the "ISO Rating" had a large impact on most fire departments. The ISO (PPC) rating is from 10 - 1. With "1" being the best. At one time, almost, all insurance companies calculated rates based upon the ISO rating. ISO would come to your city and assess a Public Protection Classification. They would then sell this data to the insurance companies. Just about every aspect of a city and a fire department was evaluated in determining the ISO rating. They would give points for everything from the training aids a fire department owned to the distance between fire hydrants. ISO wanted fire departments to conduct 20 hours of training per man, each month, in order to maximize points for every training aid. Historically, very few cities ever received a "Class 1" rating. There have been times where only one city, out of the nation, would receive a "1". Presently there may be as many as 40+ cities with a "1" rating in the U.S. This is still a small percentage when one considers the thousands of communities nationwide. 

Currently the City of Clinton Fire Department is rated a Class 4.