Laboratory investigation of fire protection coatings for creosote-treated timber railroad bridges
C A Clausen, R H White, J P Wacker, S T Lebow, M A Dietenberger, S L Zelinka, N M Stark
As the incidence of timber railroad bridge fires increases, so has the need to develop protective measures to reduce the risk from accidental ignitions primarily caused by hot metal objects. Of the six barrier treatments evaluated in the laboratory for their ability to protect timbers from fires sourced with ignition from hot metal objects only one intumescent coating provided adequate fire protection. The intumescent barrier treatment also met environmental, performance (e.g. bond durability) and application criteria set forth in this study. These criteria also dictated the development of a flammability test, called the hot metal test that is compatible with the fire scenario specific to this study. The hot metal test evaluates protective materials on creosote-treated timber against ignition of gases generated by an 1100ᴼC heat source.
Keywords: barrier treatment, fire retardant, intumescent, railroad, crossties, protection, creosote