Fire test methods initiation

Results small scale fire tests. Initially we had in mind to make a comparison between NT-FIRE 025 and NT-FIRE 004 "box test" since most lining materials had been classified using that method. It turned out that the gases generated by the method NT-FIRE 004 needed a very high dilution before they could be fed into our direct reading instruments. Instrumentation used for smoke stack sampling. EMP-797, turned out to be suitable for our purpose. 

A description is given of the initiatives carried out within the European Community for the harmonization of fire testing. The technical and economic reasons are explained for such initiatives, which are taken in order to remove barriers to trade from the European internal market. Of the various fire aspects, only fire reaction testing is taken into consideration here, because it appears as a major technical obstacle to the free circulation of construction materials. All possible approaches are considered for the attainment of such a harmonization and one, the so called interim solution, is fully described. The proposed interim solution, is based on the adoption of three fundamental test methods, i.e. the British "Surface Spread of Flame", the French "Epiradiateur" and the German "Brandschacht", and on the use of a rather complicated "transposition document", which should allow to derive most of the national classifications from the three test package. 

Safety of Reactive Chemicals and Pyrotechnics (Yoshida et al. 1995). Addresses both the hazardous properties of reactive chemicals and appropriate handling methods. Describes several test methods and the evaluation of fire and explosion hazards of reactive substances, including the impact of initiating events such as earthquakes. 

Before adopting this method at the ordnance plant, sections of pipelines were chosen for test samples, to determine if the swab and pig method would satisfactorily clean these contaminated pipes. One half the sections were cleaned by this method and the other half was thoroughly flushed with water. They were allowed to dry and then were subjected to initiation by fires. The sections that had been flushed with water ignited and burned vigorously. The sections that had been subjected to cleaning with the swab and pig had no product remaining that would support combustion. 

Given the unreliability of the stab-initiated tests, a second round of testing was performed using a hot nichrome wire to initiate the detonators in place of the NOL-130 stab mix and firing pin. This test was successful and all nine detonators functioned, showing that DBX-1 is more susceptible to this method of initiation. Figure 8 shows the electrical ignition setup. 

Special permitted explosives are tested under much more drastic conditions. As previously stated 1 kg of inversely-initiated explosive is fired creating a cloud of coal-dust. The number of test shots should not be less than 20. Safety in the. presence of coal-dust is also tested by a special method worked out by Cybulski, which consists in firing two charges, each weighing 1 kg, simultaneously from two opposite mortars. The distance between the mortars is 1 m. A cloud of coal-dust is obtained as described above. The charges are inversely initiated. The number of shots is 20. The test is considered exceptionally stringent. Such tests are repeated from time to time for inspection purposes. 

During the initial stages of a fire, fire-retardant-treated wood contributes less heat than does untreated wood, especially from the flammable volatiles (8,26). This means that the spread of fire to nearby combustibles is slow. The fire tends to be confined to the primary source. In the ASTM E84 test for building materials, treated specimens produce about 75 percent less heat than untreated red oak. In a total combustion test, however, such as the National Bureau of Standards potential heat method (54), both treated and untreated wood release about the same total heat. 

Method 13 - A 1-5/8-inch diameter, 5-inch long uncased charge is fired on a 1-3/4-inch thick, 5-square inch cold-rolled steel plate, with one or more similar plates as backing. The charge is initiated with a No. 8 detonator and two 1-5/8-inch diameter, 30-g Tetryl boosters. Plate dent test value, or relative brisance =... 

Basic Mechanisms. Finally, further work is necessary on fundamental mechanisms of individual fire retardants. These mechanisms are a function of the particular chemicals involved and the environmental conditions of the fire exposure. There is a need to establish common methods and conditions for determining these mechanisms in order to compare different treatments. This would give us a better understanding of how these compounds work in action and would provide a more efficient approach for formulating fire-retardant systems than a trial and error approach. Correlations also need to be established between rapid precise thermal analysis methods and standard combustion tests. Retardant formulations could be evaluated initially on smaller (research and development size) samples. The more promising treatments could be tested for flame-spread index, heat release rate, and toxic smoke production. 

Binary munitions are those in which the chemical substances are held in separate containers and react when mixed or combined. This may happen during firing, launching, or by other initiation methods. The product is a chemical agent or material agent. Binary components must be tested for individually because in a burial situation they may not be combined. Care must be taken not to mix chemical agents found at post-World War II sites (i.e., compositing soil samples). 

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