ISO stands for Insurance Service Office and is an organization that collects statistics about fire departments and then provides each fire department with a rating based on several factors. Ratings go from Class 1-10 with 1 being the best fire protection and 10 being the worst. Insurance companies then use this rating to base insurance rates off of. Homes and Businesses that are in an area covered by a fire department with a lower ISO rating will receive a lower premium on their insurance as opposed to an area that is covered by a fire department with a higher ISO rating.
If you would like more information about the ISO and how this system works, you can CLICK HERE for more information.