Before revision: c.1876 In the United States, according to NFPA, structures are divided into five construction types for the purposes of firefighting, and are listed from least combustible to most combustible : Type I: Fire Resistive Typically used in high-rises.
After revision: c.1876 In the United States, according to NFPA, structures are divided into five construction types based on the severity of the fire hazard : Type I: Fire Resistive Typically used in high-rises.