Explosive Materials, Characteristic Data

The information to be compiled about the chemicals, including process intermediates, needs to be comprehensive enough for an accurate assessment of the fire and explosion characteristics, reactivity hazards, the safety and health hazards to workers, and the corrosion and erosion effects on the process equipment and monitoring tools. Current material safety data sheet (MSDS) information can be used to help meet this requirement but must be supplemented with process chemistry information, including runaway reaction and over-pressure hazards, if applicable. 

Characteristic Data (Safety) for Explosive Materials. See Vol 2 of Encycl, p C148-R... 

Characteristic Data(Safety) for Explosive Materials. Under the title "Sicherheitstechnische Kenndaten explosivfahiger Stoffe , H.Koenen, K.H.Ide et al, describe in Explosivst 1961,... 

Dow Fire and Explosion Index (F EI) A method (developed by Dow Chemical Company) for ranking the relative fire and explosion risk associated with a process. Analysts calculate various hazard and explosion indexes using material characteristics and process data. 

Material Safety Data Sheets, which are now required to be provided by distributors and manufacturers of commercial chemicals, give detailed information on the characteristics of all commonly sold laboratory chemicals. The definitions of explosive, flammable, combustible, and various healthhazards are consistent with those provided by OSHA in CFR 29, Parts Table 3.2 Exemption Limits for a Few Critical Classes of Materials Representing Health Hazards For a Class 4, Hazardous Use Occupancy... 

The data to be listed on the Material Technical Sheet needs to be comprehensive enough for an accurate assessment of the fire and explosion characteristics, reactivity hazards, corrosion or erosion effects, and safety, health, and environmental hazards. 

The first step in the design of an explosion suppression system is to establish the propagation characteristics of the material in question. First, a sample of the fuel-air mixture is introduced into a cylindrical or spherical vessel, oxidation is initiated by the application of a spark, and the test data are recorded. For example, the radial flame velocity of H2 in air is 9 m/s (30 ft/s). 

Explosions involving organic dusts can usually be contained in equipment that can withstand about 7-10 times the initial pressure (Lees, 1980). Thus, if the system is originally at atmospheric pressure, the maximum pressure to be expected is about 100-150 psig. Data on explosion characteristics of the actual material to be processed are usually necessary to confirm the required design pressure. 

The various parameters and characteristics of the impact tests, and of the materials tested, should be included and interpreted with the data. Levy [27] derived a probability equation based on the Picatinny Arsenal machine and the explosive tested which required that only a few points be obtained on a % fire curve in order to determine the sensitivity of a sample. 

An extensive series of laboratory tests have been conducted in various countries to enable the investigation of lire and explosion characteristics of materials to be made. The testing apparatus and procedures differ from one conntry to the other, although there are some conunon points. The tests nsed to be made on a laboratory scale and the results obtained were extrapolated to full scale, always giving some uncertainty. Also, the test procedures may not reflect exactly the condition in a particular type of dryer. Therefore, it is reconunended that published data may be used carefully and individual tests on the particular dust concerned may be required. 

This handbook is designed to provide general information on the basic principles of TA and a variety of its applications. It is composed of two 1915 parts. Part I deals with information on the transition, reaction and characteristic parameters of substances. It introduces general principles, data 1919 treatment, experimental procedures and data analysis. Part II presents about 1000 typical 1945 thermal analysis curves, with brief explanations, for a wide variety of materials, such as polymers, 1960s foods, woods, minerals, explosives, inorganic compounds, and their coupled simultaneous 1964 curves. TA charts have been contributed by Institutes and Universities in China. Part III cites 1965 various data tables relating to thermal analysis. 

Over the past several decades, military explosives have been based largely on the nitramines RDX and HMX, TNT and inert binders such as waxes or polyurethanes. New compositions have involved only relatively minor variations and a substantial base of empirical test data has been built up against which experts can assess the likely characteristics of a new formulation. The advent of new molecules in explosives compositions changes all of this. The same tests may be applied to the materials, but without knowledge of the fundamental physics and chemistry underlying the test responses how are these results to be extrapolated to the munitions scale ... 

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