Fire tests typically relate to two types of fire properties, fire resistance and reaction to fire. Fire resistance is the ability of a building element or component to prevent the passage of heat and flames from one side to another, while reaction to fire is the response of a material or product in contributing to the development and spread of a fire. Fire resistance tests are usually performed on systems or assemblies, such as walls, floors, doors, or windows, while reaction to fire tests are usually performed on materials or products, such as sealants, insulation, cladding, or plastics.References:International Standards and Classifications for Fire Testing - Sika;Testing for Fire Resistance and Reaction to Fire – ICC NTA;‘Reaction to Fire’ Vs ‘Fire resistance’ - Ask HILTI;What is the difference between Reaction to Fire and Resistance to Fire …;Reaction to Fire vs Resistance to Fire | Nullifire UK