Insurance Services Office or 'ISO' is a private corporation that evaluates industries for insurance rating purposes.
The Public Protection Classification program is a rating system with a range from 1 (best) to 10 (worst) that numerically ranks a community's municipal fire protection system. Class 1 represents an excellent fire protection system, and class 10 indicates virtually no protection.
ISO collects information about municipal fire protection efforts in communities throughout the United States and in each of those communities, ISO analyzes and assigns a Public Protection Classification (PPC) - a number from 1 to 10. Class 1 generally represents superior property fire protection, and Class 10 indicates that the area's fire suppression program does not meet ISO's minimum criteria.
Virtually all U.S. insurers of homes and business property use ISO's Public Protection Classifications in calculating premiums. In general, the price of fire insurance in a community with a good PPC is substantially lower than in a community with a poor PPC, assuming all other factors are equal. For more information, please reference: ISO's Brochure