Insurance Service Office (ISO) Rating

Information on Northwest Fire District's ISO Rating


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Enhanced ISO Rating Places Northwest Fire Community in Top 1% Nationwide

The Northwest Fire District proudly announces an improved Class 1/1Y Public Protection Classification (PPC) rating issued by the Insurance Service Office (ISO) which places the District’s fire protection community in the top 1% in the country. The enhanced score takes effect on July 01, 2019 and works to ensure lower insurance costs for property owners within the Northwest Fire District, including much of the Town of Marana and areas of unincorporated Pima County northwest of Tucson. 

ISO collects and evaluates fire suppression capabilities in over 48,000 communities in the United States. ISO notes that most insurers use the PPC classification for underwriting and calculating premiums on residential, commercial, and industrial properties. The PPC score is a measure of the community’s overall ability to reduce property losses due to fires.  

The scale of a PPC rating ranges from 1-10, with Class 1 being the highest rating. Northwest Fire’s community Class 1 PPC rating, improved from Class 2, comes on the heels of a recent analysis performed by the ISO on the Northwest Fire community’s fire prevention and suppression systems.  

The ISO is one of two third-party entities that regularly assess the Northwest Fire District. The Commission on Fire Accreditation International also evaluates Northwest Fire District is one of only 258 accredited fire and rescue agencies in the country. 

The chart below shows the distribution of PPC Ratings for fire protection districts nationwide.

PPC Grade Distribution Chart

With an ISO Rating of Class 1, this makes Northwest Fire District one of only 348 agencies nationwide to achieve this rating, putting us in the top 1% of fire protection communities.

July 1, 2019

2 / 2Y

ISO Rating Letter

How Does ISO Rating Affect District Residents?

In addition to showing district boundaries, stations and facilities, the Interactive Map allows you to enter an address and verify if it is in the Northwest Fire District.

How NWFD’s ISO Rating Affects District Residents

Ratings range on a scale of 1 to 10, with 1 being the best rating. A lower ISO rating is achieved by upgrading a community’s fire prevention and suppression capabilities, specifically in the categories of dispatch, water supply, and fire suppression. In short, better prevention efforts and response capabilities can lower insurance premiums. NWFD’s current ISO rating is a split rating of 1/1y. The first number (1) refers to the classification of properties within 5 road miles of a fire station and 1,000 feet of a hydrant. The second number (1y) refers to properties within 5 road miles of a fire station but beyond 1,000 feet of a hydrant. For properties that fit the second classification, NWFD utilizes water tenders which carry close to 3,000 gallons of water, and/or may deploy a water shuttle operation requiring multiple water tenders. In order to qualify for this rating, NWFD firefighters train hard to achieve the standards required by ISO. There are approximately 30,000 fire departments in the country with an ISO rating, less than 1% of which are rated as a class 1.

ISO Public Protection Program

For more information regarding the ISO Public Protection Program, visit:


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