UL 1709:2017 pdf free download – STANDARD FOR SAFETY Rapid Rise Fire Tests of Protection Materials for Structural Steel.
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 minimum 0.032 in (0.8 mm) diameter (No. equivalent having a time constant of 2 s or
recording specimen temperature are to be fabricated from 20 B & S gauge) chromel-alumel, inconel sheathed wires or less.
5.6 The applied protection material is to be restrained against longitudinal thermal expansion greater than that of the steel column by attaching rigid steel plates or reinforced concrete to the ends of the steel column prior to application of the protection material. The plates or concrete are to be sized to provide direct bearing over the entire transverse area of the protection material.
5.7 The ends of the test specimen, including the means for restraint, are to have sufficient thermal insulation to prevent significant direct heat transfer through to the ends of the steel section from the furnace.
5.8 Prior to test, the test specimen is to be conditioned such has achieved a moisture content corresponding to drying to relative humidity at 73 ±5°F (22.8 ±2.8°C). If the protection to perform as intended, such moisture content may be justification of acceptance are documented in the report, classification.
that the dampest portion of the test specimen equilibrium with air in the range of 50 to 75% product requires a different moisture content allowed provided the moisture content and and the moisture content is included in the
5.9 Moisture content equilibrium with air shall be determined to have been reached when successive weekly weighings of a representative specimen, prepared at the same time as the test specimen, indicate that the representative specimen has stopped losing weight.
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).
7 Environmental Performance
7.1 Products evaluated for fire endurance under the requirements of this Standard shall also comply with the applicable performance requirements in UL 2431 for Material Classification Category I-A: Outdoor, Heavy Industrial.
8 Applicability of Results and Classification
8.1 An individual classification of a column or beam may be obtained by the tests described within this document and based upon the performance criteria specified in Performance Criteria, Section 6. The fire endurance classification is applicable to the column or beam when used in a type of construction representative of the design that the test is intended to examine.