UL 1489-2016 pdf download – Fire Tests of Fire Resistant Pipe Protection Systems Carrying Combustible Liquids.
5.2 Conditioning 5.2.1 Prior to fire testing, each fire resistive pipe protection system and floor or wall assembly is to be conditioned, if necessary, to provide a moisture condition representative of that likely to exist in similar constructions in buildings. The floor or wall assembly may be conditioned independently of the fire resistive pipe protection systems. The test moisture condition is to be considered as that which would be established in equilibrium resulting from drying of a sample in air having 50% relative humidity at 73°F (23°C). If it is impractical to achieve this equilibrium moisture condition, the test may be conducted when the dampest portion of the test assembly and test sample have achieved an equilibrium moisture content corresponding to drying in air having 50 to 75% relative humidity at 73 ±5°F (23 ±3°C). Exception: These requirements may be waived if: a) An equilibrium moisture condition is not achieved within a 1 2 month conditioning period; or b) The construction is such that drying of the interior of the assembly is prevented by hermetic sealing of the construction materials. In these cases, the conditioning need then be continued only until the test assembly has developed sufficient strength to retain the test samples securely in position. 5.2.2 A procedure with electric sensing elements may be used to determine the relative humidity within a test assembly and test sample made of materials other than concrete. 5.3 Protection of assembly and sample 5.3.1 The testing equipment, test sample and assembly are to be protected from any condition of wind or weather that might influence the test results. The ambient air temperature at the beginning of the test is to be within the range of 50 to 90°F (1 0 to 32°C). The velocity of air across the unexposed surface of the test sample, measured immediately before the test begins, is not to exceed 4.4 ft/s (1 .3 m/s) as determined by an anemometer placed at right angles to the unexposed surface.