UL 1709-2017 pdf download – Rapid Rise Fire Tests of Protection Materials for Structural Steel.
4.3 The temperature of the furnace is to be measured by eight thermocouples, each located 4 in (102 mm) from the exposed face of the calibration column and at the 1/3 and 2/3 heights. 4.4 The measured values of all thermocouples and calorimeters are to be recorded at intervals not exceeding 1 min. 4.5 The thermocouples used to measure the temperatures on the face of the calibration column are to be No. 28 gauge, Type K inconel sheathed thermocouples having a time constant of 0.5 s or less. The thermocouple junction is to be located 1/4 in (6.3 mm) from the face of the calibration column. 4.6 The thermocouples used to measure the temperatures within the furnace are to be constructed as described in 3.6. 4.7 The calorimeters are to have a minimum range of 100,000 Btu/h·ft 2 (315 kW/m 2 ) and a 180° view angle. 4.8 Combustion gas samples from within the furnace are to be obtained from a probe of stainless steel tubing having an outer diameter not less than 3/16 in (4.7 mm) and a wall thickness not less than 1 /32 in (0.8 mm). The probe tip is to be positioned vertically at the midheight of the calibration column and horizontally located 4 in (102 mm) from the face of the calibration column. 4.9 The combustion gas samples are to be obtained continuously by use of a vacuum pump and the oxygen content measured by an oxygen analyzer. 4.10 The fire environment during the calibration test is to comply with the requirements of 3.1. The length of the calibration test is to be 60 min. 4.11 Individual total heat flux measurements are to lie within the limits shown in Figure 4.3.
5.3 The temperature of the open section is to be measured by no fewer than five thermocouples located at each of four levels (minimum of 20 thermocouples). The upper and lower levels are to be 2 ft (610 mm) from the ends of the steel column, and the other two intermediate levels are to be equally spaced between the upper and lower levels. The thermocouples at each level are to be placed to measure significant temperatures of the component elements of the steel column. Figure 5.1 shows required locations of thermocouples on wide flange and tubular steel columns. 5.4 The temperature of the hollow section is to be measured by no fewer than four thermocouples located at each of four levels (minimum of 16 thermocouples). The upper and lower levels are to be 2 ft (610 mm) from the ends of the steel column, and the other two intermediate levels are to be equally spaced between the upper and lower levels. The thermocouples at each level are to be placed to measure significant temperatures of the component elements of the steel column. Figure 5.1 shows required locations of thermocouples on tubular steel columns. 5.5 All thermocouples for the purpose of recording specimen temperature are to be fabricated from minimum 0.032 in (0.8 mm) diameter (No. 20 B & S gauge) chromel-alumel, inconel sheathed wires or equivalent having a time constant of 2 s or less.