Insurance Services Office Rating (ISO)

What is this ISO number?

Insurance Services Office (ISO) is a research group funded by the insurance companies. You can find out more on their website.

Based on their research, ISO provides a Public Protection Classification rating to each fire department. This rating is thus assigned to properties found within the department's service area.  This PPC is, in many ways, a measure of the fire protection services you receive from your local fire department. It is one of the factors that your insurance company should be using to set your insurance rates. 

The PPC rating depends ISO's review of various components of your fire department. These include:

1) The Dispatching/ Communications system- (roughly 10 percent of your rating) 

2) The Capabilities of the Fire Department itself; stations, personnel, apparatus, etc..-  (roughly 50 percent of your rating)

3) The Water Supply system, are the three largest factors that determine your PPC ranking. - (roughly 40 percent of your rating)

The aggregate score, on a 105-point scale, is becomes your PPC rating: 

  • A Class 1 = 90.00 or more points

  • A Class  2  = 80.00 to 89.99

  • A Class 3 = 70.00 to 79.99

  • A Class 4 = 60.00 to 69.99, as so on........

ESD 4's ISO History

- In December of 2010, we were rated as a split classification of Class 6 / 9.

(The first number means the property is within 5 road-miles of a fire station and within 1000 feet of a fire hydrant. The second number means you were within five miles of a fire station, but had no fire hydrants within the 1000 feet)

- In May of 2011, the rating was improved to a Class 4/ 8B. 

(Note in 2011, we did not receive credit for neighboring Austin Fire stations, Austin Fire Engines/Trucks or Austin Fire Personnel, because we did not have a Service Contract or an Auto-aid agreement in place.)

-Fall of 2017- Both ESD4 and AFD have initiated another department review to reflect the increase in fire stations and fire companies, with the expectation that our classification will see improvement. 


Regarding the split classifications. 

1) The vast majority of the properties will receive the first number, currently a Class 4 that we are hoping to improve. 

2)  If the home is not within 5 road-miles of a fire station the classification will be a  Class 10; fire hydrants do not matter in that case.

3) Also, if your home is within the 5 miles, but you do not have a fire hydrant within 1000 feet you should receive a Class 1Y.