Compressed gas definition

Gas chromatography. See Analytical techniques Gas Safety (Installation and Use) Regulations 1994, 595 Gas Safety (Management) Regulations 1996, 484 Gases, See also Asphyxiants Compressed gases definition, 26... 

Aerosol technology may be defined as involving the development, preparation, manufacture, and testing of products that depend on the power of a hquefied or compressed gas to expel the contents from a container. This definition can be extended to iaclude the physical, chemical, and toxicological properties of both the finished aerosol system and the propellants. 

Cryogenic Liquid A cryogenic liquid is a refrigerated liquefied gas having a boiling point colder than -130 °F at one atmosphere, absolute. A material that meets this definition is subject to the same requirements tor compressed gases widrout regard to whether it meets the standard definition of a compressed gas. 

Dry-powder inhalers (DPIs) deliver the drug to the respiratory tract in aerosol form. An aerosol is by definition a suspension of free liquid or solid fine particles in a gas phase, which is air in the case of DPIs (and a compressed gas in the case of needle-free injection). The most prominent characteristic that determines the delivery of drug particles to the lungs is the particle size, although particle shape and density are also of considerable importance for the behavior of an aerosol in the respiratory tract (Brain and Blanchard 1993 Gonda 1992 Heyder et al. 1986 Agnew 1984 Heyder et al. 1980). 

By definition, the particles of gases are far apart and gases tend to fill their container, even if the container is a laboratory room. Tanks of compressed gas come from the supplier capped to prevent the gas from escaping. In the lab a chemist or technician attaches a regulator to the tank and secures the tank to a stable fixture. 

If a compressed gas does not meet the criteria of flammability, it is obviously a non-flammable gas. Other definitions involved are ... 

ANSI Z49.1,10.8.2.1 CGA G-1,4.2.8 CGA P-1,3.7.4 NFPA 55,2.2.1.6 NFPA 55, 7.1.3.4 NFPA 55, 7.2.1.2 29CFR1910.253(b)(2) (ii) 4.2.3 Compressed gas cylinders shall be stored in an upright position (see definition) with their valve protection caps in place and secured to prevent cylinders from falling over or being knocked over. [EXCEPTION All requirements cited here indicate that upright storage is not required for lecture bottles or cylinders used in self-contained breathing apparatus.]... 

Currently there are more than 200 different substances commonly shipped in compressed gas containers that can be considered compressed gases. The Department of Transportation (DOT) defines these materials based on their properties such as vapor pressure, flammability, toxicity, and physical state in the container. The specific definitions in this handbook according to DOT classification are in three Class 2 compressed gas divisions 2.1... 

Definitions for terms commonly used for the visual inspection of compressed gas cylinders are as follows ... 

Reservoir fluids (oil, water, gas) and the rock matrix are contained under high temperatures and pressures they are compressed relative to their densities at standard temperature and pressure. Any reduction in pressure on the fluids or rock will result in an increase in the volume, according to the definition of compressibility. As discussed in Section 5.2, isothermal conditions are assumed in the reservoir. Isothermal compressibility is defined as ... 

A key limitation of sizing Eq. (8-109) is the limitation to incompressible flmds. For gases and vapors, density is dependent on pressure. For convenience, compressible fluids are often assumed to follow the ideal-gas-law model. Deviations from ideal behavior are corrected for, to first order, with nommity values of compressibihty factor Z. (See Sec. 2, Thvsical and Chemical Data, for definitions and data for common fluids.) For compressible fluids... 

How big is an atom or a molecule It should be fairly obvious that atoms and molecules do take up a definite amount of space. A gas can be compressed into a smaller volume but only so far. Liquids and solids cannot be easily compressed. While the individual molecules in a gas are widely separated and can be pushed into a much smaller volume, the molecules in a liquid or a solid are already close together and cannot be squeezed much further. The bottom line is that atoms and molecules require a certain amount of space. But how much ... 

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