UL 10B:2008 pdf download – Fire Tests of Door Assemblies.
4A Furnace Pressure
Added 4A elleclive Felxuary 16, 2018
4A.1 Furnace pressures are to be read at intervals not exceeding 1 minute.
4A2 The neutral plane within the test furnace shall be established prior to the initiation of the tie test. Such pressure shall remain constant or increase to maintain the neutral plane upon initiation of the fire test. Control of the furnace pressure Is to be established beginning no later than 5 minutes after the start of the test and is to be maintained throughout the remainder of the fire test.
4A.3 The vertical pressure distribution within the furnace Is to be measured by at least two pressure-sensing probes separated by a minimum vertical distance of 6 ft (1.8 m) inside the furnace for furnaces with a minimum vertical dimension of 10 ft (3.05 m). Minimum vertical separation between pressure probes Is to be reduced proportionally for furnaces with an internal dimension less than 10 ft (3.05 m).
4A.4 The pressure-sensing probes are to be as shown In either Figure 4A.1 or Figure 4A.2. The probes are to be located so that the center line of the sensing holes are positioned 6 ±1 in (152 ±2.5 mm) from the surface of the exposed face of the test assembly and a minimum of 18 in (457 mm) from the edges of the furnace. The probes are to be positioned horizontally in the furnace without a change in vertical elevation of the probes or tubing within the furnace.
4A5 The pressure-sensing probes are to be located at a minimum of 18 inches from the edges of the furnace chamber.
4A6 The pressure at each location is to be measured usrng a differential pressure instrument capable of reading In increments no greater than 0.01 inch water gauge (2.5 Pa) with an accuracy of ±0.005 inch water gauge (±1.2 Pa) or better. The differential pressure measurement instrument is to be located so as to minimize stack effects caused by vertical runs of pressure tubing between the pressure-sensing probes and the differential pressure measurement instrument locations.
4A.7 Based on the vertical separation and pressure differences between the two pressure•serising probes, a calculation of the zero pressure plane is to be made. The furnace pressure is to be positive above the zero pressure plane.
5 Unexposed Surface Temperatures
5.1 Unexposed surface temperatures are to be recorded, and are to be determined in the following manner.
Exception: Single-layer metal doors are not required to comply with this section.
5.2 Unexposed surface temperatures are to be taken at not less than three points, with at leasi one thermocouple in each 16-square foot (15-m2) area of me door. Thermocouples are not to be located over reinforcements extending through the door, over glass panels, or nearer than 12 inches (305 mm) from the edge of the door.
53 Unexposed surface temperatures are to be measured with thermocouples placed under flexible, oven-dry, fetted pads. The properties of these pads are to comply with the requirements specified in Appendix B. The thermocouple and telted pad are to be fixed to the surface of the test specimen by mechanical fastening, tape or adhesive, based on the nature of the material forming the specimen. When a mechanical fastening method is used to secure the thermocouple and felted pad, the testing laboratory shall ensure the fastener is not greater than 3/8 inch in length. The pads shall be fixed so as to maintain contact between the thermocouple and the surface of the test specimen.
Revised 5.3 &teive Felxuafy 16. 2016
5.4 Unexposed surface temperatures are to be recorded at intervals not exceeding 1 minute for the first 30 minutes of the test. After 30 minutes the thermocouples and the felled pads are to be removed unless the sponsor requests additional surface temperatures be recorded.