Since the late 1970s, the AAIS method allowed insurers to place a risk in one of three fire protection classifications:
- Protected – buildings located within 1,000 feet of a fire hydrant and within five road miles of a responding fire department. Protected is further broken down by how far a property is from a station, with values of P1 (within 1 mile) thru P5 (within 5 miles)
- Partially Protected – buildings located more than 1,000 feet from a fire hydrant but within five road miles of a responding fire department. Partially Protected is further broken down by how far a property is from a station, with values of PP1 (within 1 mile) thru PP5 (within 5 miles)
- Unprotected – buildings that are not classified as Protected or Partially Protected. HazardHub also provides the distance to the nearest fire station, with values ranging from U6 (within 6 miles) to U40 (within 40 miles)