Panel Test Setup

The UL 94 standard specihes bench-scale test methods to determine the acceptability of plastic materials for use in appliances or other devices with respect to flammability under controlled laboratory conditions. The test method that is used depends on the intended end-use of the material and its orientation in the device. The standard outlines two horizontal burning tests, three vertical burning tests, and a radiant panel flame spread test. The most commonly used test method described in the UL 94 standard is the 20-mm Vertical Burning Test V-0, V-l, or V-2. The method is also described in ASTM D 3801. A schematic of the test setup is shown in Figure 14.3. 

This consists of two concentric semicircular plywood walls, with the space betw them (ca 2 wide) filled with earth. Its top is made to slope away from the center of setup so that a line joining the lower of the panel passes just above and parallel to the top of the ricochet stop. In case of testing a proj, the radius of ricochet stop is about half of the panel B radius... 

It is important to keep the test location well guarded and secured to prevent unauthorized access. The test locations must be secured with barrier tapes or other means to warn people of the hazards. If power distribution panels or switchboards are monitored, all openings created as the result of instrument setup should be sealed to prevent entry by rodents and other pests. All these steps are necessary to ensure that the tests will be completed without accidents. 

Figure 24.14 The left panel is a plan of the testing area near the LENS (reflected shock) tunnel 1 — 8 test section 2 — TDL probe 3 — 4 nozzle M = 8-16 4 — 8" reflected shock tube 5 — fiber optic and signal line conduit 6 — data acquisition and 7 — TDL system optical table. The right panel is a schematic diagram of the setup used to record water-vapor absorption in high-enthalpy flows 1 — InGaAs detectors 2 — tunable diode laser Ai = 1400.74 nm 3 — ring interferometer 4 — tunable diode laser A2 = 1395.69 nm and 5 — HoO reference cell...

Carbon monoxide has a large attenuation coefEcient for absorption of IR radiation. Therefore, the SNIFTIRS spectra of CO adsorbed at a Pt electrode surface are a convenient standard to test the S/N of a spectroelectrochemical setup. The left panel in Fig. 9.11 shows SNIFTIRS spectra of a monolayer of CO at Pt electrode surface recorded using a cell equipped with a Cap2 prism [91]. The right panel shows similar spectra recorded using a ZnSe hemispherical window. The IR bands of CO adsorbed at Pt are significantly Stark-shifted when the electrode potential is modulated between -200 and -f200 mV versus SCE. Consequently, the potential difference spectrum displays bipolar bands. Clearly a much better S/N for these bands is achieved when a ZnSe hemisphere is used as the window. 

Basically the test involves mounting a corner section specimen - a vertical 1.5 m high by 1.0 m wide panel and another 1.5 m by 0.5 m at 90 degrees - under an enclosed calorimeter bood. Tbe Fire Research Station says the setup can accurately measure the rate of heat release, considered one of the most important parameters in assessing fire growth, also time to ignition, rate of lateral flame spread, time of production of flaming droplets and rate of smoke release. 

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