UL-1709:2011 pdf free download – Underwriters Laboratories Inc. Standard for Safety Rapid Rise Fire Tests of Protection Materials for Structural Steel.
5.5 Prior to test, the test sample is to be conditioned such that the dampest portion of the test sample has achieved a moisture content corresponding to drying to equilibrium with air in the range of 50 to 75% relative humidity at 73 ±5°F (22.8 ±2.8°C).
6 Performance Criteria
6.1 The transmission of heat through the protection material during the period of fire exposure for which Classification is desired shall not raise the average temperature at any of the four levels of the steel column above 1000°F (538°C) and no thermocouple shall indicate a temperature greater than 1200°F (649°C).
SMALL-SCALE TEST METHOD
7 Furnace Control During Fire Test
7.1 The average furnace temperature curve shall be reproduced to maintain the furnace control described in Furnace Control, Section 3.
7.2 The temperature near all parts of the assembly, as obtained from the average of the readings of four thermocouples symmetrically disposed within the test furnace is to comply with the time-temperature curve of Figure 3.1.
7.3 The thermocouples are to be constructed as specified in 3.5.
8 Test Sample
8.1 The test sample is to be a 2 ft by 6 by 6 in (610 by 152 by 152 mm) structural steel tube with a 3/1 6-in (4.8-mm) wall thickness. The steel tube is to be provided with steel caps and covered with the protective material being investigated. Figure 8.1 shows the details of a test sample prior to application of the protective material.
8.2 The temperatures of the test sample are to be measured with five Type K thermocouples having a time constant not greater than 2 s and located within the steel tube as shown in Figure 8.1.
8.3 The protective material shall be sufficient to provide at least a 50 mm resistance, but not more than a 90 mm resistance in compliance with the requirements of 9.1.
8.4 The test sample is to be conditioned in compliance with the requirements of 5.5 prior to the test.
8.5 After conditioning, and prior to test, the test sample is to be subjected to the selected environmental exposure simulations described in Appendix A to which it is anticipated that the protective material will be subjected to during its intended use. Other environmental exposures may be simulated in addition to those described in Appendix A.
9 Test Method
9.1 A test sample is to be conditioned as specified in 5.5, and subjected to the temperatures specified in 7.2. The thickness of the protective material shall be such that the time at which the test sample reaches an average temperature of 1000°F (538°C), and no thermocouple indicates an individual temperature greater than 1200°F (649°C), in no less than 50 mm and no greater than 90 mm after the beginning of the test. This time is to be defined as the control period, If necessary, the thickness of the protective material may be varied from one test sample to another to determine the thickness necessary for compliance with this requirement. This thickness, once determined, is to be the thickness applied to subsequent test samples.
9.2 Test samples after exposure to simulated environmental conditions described in 8.5 are to be fire tested in accordance with Furnace Control During Fire Test, Section 7.
10 Performance Criteria
10.1 The average temperature of the test samples shall not exceed 1000°F (538°C) and no thermocouple shall indicate a temperature greater than 1200°F (649°C) within a time equal to three quarters of the control period (see 9.1).