Gas explosions

To find explosives Gas analyzers, chromatography instruments, drift-spectrometers, neutron defectosopes, nuclear-magnetic and nuclear-quadrupole resonant instruments... 

An electrolytic cell, preferably having anode and cathode compartments separated by a porous membrane to prevent formation of explosive gas mixtures, is required (27). 

Chlorine dioxide, CIO2, is another chlorine derivative. This unstable, potentially explosive gas must be generated at the point of appHcation. The most common method of generating CIO2 is through the reaction of chlorine gas with a solution of sodium chlorite. 

In addition to chemical synthesis and enhanced oil recovery, gaseous carbon dioxide is used in the carbonated beverage industry. Carbon dioxide gas under pressure is introduced into mbber and plastic mixes, and on pressure release a foamed product is produced. Carbon dioxide and inert gas mixtures rich in carbon dioxide are used to purge and fiH industrial equipment to prevent the formation of explosive gas mixtures. 

Process Safety Considerations. Unit optimization studies combined with dynamic simulations of the process may identify operating conditions that are unsafe regarding fire safety, equipment damage potential, and operating sensitivity. Several instances of fires and deflagrations in ethylene oxide production units have been reported in the past (160). These incidents have occurred in both the reaction cycle and ethylene oxide refining areas. Therefore, ethylene oxide units should always be designed to prevent the formation of explosive gas mixtures. 

Rotating electrical machines starting performance of single-speed three-phase cage induction motors for voltages up to and including 690 V Electrical apparatus for explosive gas atmosphere. Increased safety protection e 8789/1996 6381/1991 BS EN 60034-12/1996 BS 5501-6/1977... 

Electrical apparatus for explosive gas atmospheres Increased safely motors, type e . General requirements 6381/1991 BS. 5501-6/1977 BS 5000-15/1985 ... 

Electrical apparatus for explosive gas atmospheres. Increased safety motors. General requirements 6181/1991 BS 5501-6/1977 -... 

Confined vapour eloud explosion gas or vapour burns in a eonfined volume and rapid expansion of the eombustion produets is restrained until failure of the eontainer or building oeeurs. 

Zone 0 Area in which an explosive gas-air mixture is continuously present, or present for long periods... 

AMD 1 Electrical apparatus for explosive gas atmospheres. Classification of hazardous areas (AMD 9340) dated 15 November 1996. Superseded BS 5345 Part 2 1983... 

AMD 1 Electrical apparatus for explosive gas atmospheres. Electncal installations in hazardous areas (other than minesj. Comgendum No. 1 (Corr. 10013J dated April 1998, superseded BS 5345 Part 1 1989, Parts 2 and 7 1979, Part 4 1977, Part 5 1983, Part 6 1978 and Part 8 1980... 

On the simplest type of instrument (an explosimeter) only one scale is provided, usually with readings from 0 to 100% LEL. However, the detectable changes produced by combustion are too small to be measured accurately in the presence of the low concentrations of contaminants usually encountered in evaluating potential health hazards. For example, the LEL of even the most explosive gas is of the order of 1 %, or 10,000 ppm, which is well in excess of the toxic limit for any gas. Therefore, explosimeters or combustible gas indicators which have only a 0-to-l(X)% LEL explosive scale are not suitable for environmental health testing in the ppm range. More sensitive instruments, including the type used in sampling for environmental health purposes, have a dual scale, in which the second, more... 

The European philosophy on area classification varies from that of the United. States and Canada. Specifically, in Europe and most other inter national areas, the Zone concept is utilized. An area in which an expio sive gas-air mixture is continuously present, or present for long perioiK of time, is referred to as Zone 0. The vapor space of a closed, but vented, process vessel or storage tank is an example. An area in which an explosive gas-air mixture is likely to occur in normal operations is designated Zone 1. An area in which an explosive gas-air mixture is less likely to occur, and if it does occur will exist only for a short time, is designated Zone 2. Zone 0 and Zone 1 correspond to Division 1 in the U.S. and Canada System. Zone 2 is equivalent to Division 2. 

K or K, values, which are a measure of the character-istic for the course of an explosion (gas or dust) of vessels roughly cubic in shape, are termed deflagration indices. 

FPN No. 1) As a guide in determining when flammable gases are present continuously, for long periods, or under normal conditions, refer to. Recommended Practice for Classification of Locations for Electrical Installations of Petroleum Facilities, API RP 500-1991, Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous Areas, lEC 79-10 and. Institute of Petroleum Area Classification Code for Petroleum Installations, IP 15. 

Treat the odd electron like a lone pair.) (a) NO2, nitrogen dioxide (red-brown gas that pollutes the air over many cities) and (b) CIO2, chlorine dioxide (highly explosive gas used as an industrial bleach). 

The use of electrical equipment in hazardous areas is covered by British Standards BS 5345 and BS 5501. The code of practice, BS 5345, Part 1, defines hazardous areas as those where explosive gas-air mixtures are present, or may be expected to be present, in quantities such as to require special precautions for the construction and use of electrical apparatus. Non-hazardous areas are those where explosive gas-air mixtures are not expected to be present. 

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