ISO Class Two

ISO Class 2 Rating

ISO classification refers to the Public Protection Classification (PPC) service administered by the Insurance Service Organization (ISO). This classification system gauges the capacity of a local fire department to respond to fires.

The ISO uses their Fire Suppression Rating Schedule (FSRS) in reviewing the fire-fighting capabilities of individual communities. The schedule measures the major elements of a community's fire-suppression system and develops a numerical grading on a scale from 1 to 10. Class 1 represents the best public protection, and Class 10 indicates no recognized protection.

Here's how it works:

Fire alarms

Ten percent of the overall grading is based on how well the fire department receives fire alarms and dispatches its fire-fighting resources. ISO field representatives evaluate the communications center, looking at the number of operators at the center; the telephone service, including the number of telephone lines coming into the center; and the listing of emergency numbers in the telephone book. Field representatives also look at the dispatch circuits and how the center notifies firefighters about the location of the emergency.

Engine companies

Fifty percent of the overall grading is based on the number of engine companies and the amount of water a community needs to fight a fire. ISO reviews the distribution of fire companies throughout the area and checks that the fire department tests its pumps regularly and inventories each engine company's nozzles, hoses, breathing apparatus, and other equipment.

ISO also reviews the fire-company records to determine:

  • Type and extent of training provided to fire-company personnel
  • Number of people who participate in training
  • Firefighter response to emergencies
  • Maintenance and testing of the fire department's equipment


 Water supply

Forty percent of the grading is based on the community's water supply. This part of the survey focuses on whether the community has sufficient water supply for fire suppression beyond daily maximum consumption. ISO surveys all components of the water supply system, including pumps, storage, and filtration. To determine the rate of flow the water mains provide, we observe fire-flow tests at representative locations in the community. Finally, we evaluate the distribution of fire hydrants.