Compressed Gas Association

Molybdenum hexafluoride is classified as a corrosive and poison gas. It is stored and shipped in steel, stainless steel, or Monel cylinders approved by DOT. Electronic and semiconductor industries prefer the cylinders equipped with valves which have Compressed Gas Association (CGA) 330 outlets. 

Table 7. Selected Commercial Specifications for Helium Compressed Gas Association Grades ...

Mcetylene Transmission for Chemical Synthesis, Pamphlet G 1.3, Compressed Gas Association, Arlington, Va., 1984. 

Guidelinesfor Periodic Visual Inspection and Kequalification oJA.cetylene Cylinders, Pamphlet C-13, Compressed Gas Association, Arlington, Va., 1992 A.cetylene, Pamphlet G-1, Compressed Gas Association, Arlington, Va., 1990. 

In the United States, the Compressed Gas Association Hsts nine grades of nitrogen, differentiated by oxygen content, dew point, total hydrocarbon content, and other contaminant levels (25). These grades, more often specified in government than commercial contracts, are shown in Table 3. 

Twelve oxygen grades are defined by the Gas Specification Committee of the Compressed Gas Association (CGA) (24), 10 of which are given in Table 4. The contaminants identified relate to possible residues from the atmosphere as well as particulates or fibers that may have been contributed by the manufacturing process or the distribution system. In addition, government agencies and certain commercial users have developed specifications for individual needs (25). In most cases, these specifications closely parallel the CGA grades. 

Table 4. Compressed Gas Association, Oxygen Commodity Specifications ...

Pamphlet G-2, Compressed Gas Association, American National Standards Institute, New York, 1962. 

Carbon dioxide used in carbonated beverages must be food-grade and must meet the Compressed Gas Association commodity specifications for carbon dioxide. In addition, carbon dioxide is tested for purity, taste, and odor before being used in the production of beverages. 

Decomposition Flame Arresters Above certain minimum pipe diameters, temperatures, and pressures, some gases may propagate decomposition flames in the absence of oxidant. Special in-line arresters have been developed (Fig. 26-27). Both deflagration and detonation flames of acetylene have been arrested by hydrauhc valve arresters, packed beds (which can be additionally water-wetted), and arrays of parallel sintered metal elements. Information on hydraulic and packed-bed arresters can be found in the Compressed Gas Association Pamphlet G1.3, Acetylene Transmission for Chemical Synthesis. Special arresters have also been used for ethylene in 1000- to 1500-psi transmission lines and for ethylene oxide in process units. Since ethylene is not known to detonate in the absence of oxidant, these arresters were designed for in-line deflagration application. 

CGA (Compressed Gas Association, Inc.). 1970 (Reaffirmed 1984). Acetylene Transmission for Chemical Synthesis (Recommended Minimum Safe Practices for Piping. Systems). Publication G-1.3. Compressed Gas Association, Inc., Arlington, VA. 

Sulfur Dioxide, Paniplilet G-3, 3 ed.. Compressed Gas Association, New York, 1964. 

Standards provide a base for a uniform system of accepted performance such as those found in engineering practice standards, material standards, and test standards. Hydrogen standards are typically written under a consensus process by technical committees (TC) representing a cross section of interested parties and issued in the United States, for example, by organizations such as the American Society of Mechanical Engineers (ASME) for pressure vessels, pipelines, and piping the Compressed Gas Association (CGA) for pressure vessel operation and maintenance and the Underwriters Laboratories (UL) for product certification. 

Human toxicity values have not been established or have not been published. However, based on available information, the Compressed Gas Association has established an LC50 of 260 ppm with an exposure of 1 h, or approximately one-fifth as toxic as hydrogen fluoride. 

Compressed Gas Association, Handbook of Compressed Gases. Third Edition, Van Nostrand Reinhold, New York, NY, 1990. 

Handbook of compressed gases, Compressed Gas Association Inc., New York, Van Nostrand-Reinhold, 2nd ed., 1981... 

CGA G-5.4.1 992. Standard for Piydrogen Piping Systems at Consumer Locations. Compressed Gas Association, Chantilly, VA. 

Valve outlet connection standardized by the Compressed Gas Association (CGA) (see ref. S). Corrosion of the manual control valve is indicated by sticking on opening and closing, in which case the valve is taken apart and cleaned. 

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