The IBC, IFC, and NFPA require minimum fire-resistance ratings for various building materials, components, and assemblies. These fire-resistance ratings are based on the data and testing provided by ASTM, according to the procedures outlined in ASTM E 119. These codes point the user, by reference, to ASTM E 119, Typically this reference is preceded by terminology such as, “...tested in accordance with”.
ASTM E 119 is the guiding document for the Standard Test Methods for Fire Tests of Building Construction and Materials. This document provides the fire-test-response criteria and procedures for structural materials used in building construction. The application of the test procedures contained in ASTM E 119 is to “evaluate the duration for which” building construction materials and assemblies can either contain a fire, retain structural integrity or both. The types of assemblies to be tested include, bearing walls and partitions, columns, floors and roofs, beams, and protective membranes. Specific requirements must be met for these building products to produce a successful (passing) result. These requirements are referred to as “conditions of acceptance”. The conditions of acceptance outline what makes a successful test. If these conditions are not met, then the material or assembly being tested will fail.
The fire-resistance of building materials is determined and based on the standard time-temperature curve. In this temperature controlled environment, building materials receive their hourly rating. The standard time-temperature curve looks like this:
The temperature is measured by the use of thermocouples strategically placed across the product or material to be tested. Utilizing the time temperature curve the temperature data produced by the thermocouples are read and recorded every five to ten minutes.
Both sides of the material, exposed and unexposed, are to be monitored by thermocouples. Both, the IBC and the NFPA, have requirements for nonsymmetrical building assemblies and components. Nonsymmetrical assemblies are constructed of different components on each side. Based on the order in which the materials are assembled, a fire will burn differently, or at a different rate, depending on which side the fire is on. The test report for these types of assemblies will indicate the fire-resistance rating for both sides. This is important to note, as some code requirements state that the fire-resistance rating should be based on the shortest test duration.
Building construction materials and assemblies can be subjected to two types of tests, the fire endurance test and the hose stream test. Based on the type of assembly being tested (floor, wall, column, etc.) there may be a requirement for a load to be applied. To successfully pass, the assembly or material must support the load throughout the duration of time that it is exposed to fire. The hose stream test is conducted to measure the “impact, erosion, and cooling effects” of a hose stream on the heated surface of the test material. The test types and duration required will be based on the conditions of acceptance for the material being tested.
Video of ASTM E 119 test procedure:
