Breathing atmosphere

To obtain the maximum benefits from the air, we need to breathe from the diaphragm, a muscle situated below the rib cage in the abdominal muscles. Remember, you do not have to pull in the breath atmospheric pressure will take care of that. Simply push out your diaphragm. Your rib cage will expand and air will rush into your lungs. Please do not make the mistake of trying any forcible expansion of the chest. This can cause damage to fine blood vessels in the chest. Let the muscles below your ribs do most of the work. If you do this properly, you will feel an expansion at the small of your back and at your sides, as well as in the front of your body. Always try to ensure that you commence any cycle... 

Suffocation and breathing atmospheres Each of the foregoing hazards is discussed in the following sections. Table 1 provides certain specific properties of hydrogen useful in examining the hazards discussed in the following sections (1). 

Suffocation. A most unlikely hazard would be personnel exposure to a hydrogen atmosphere sufficient to cause suffocation (a fire would be apt to occur first). However, it must be borne in mind that hydrogen is as dangerous as the inert gases in dilution of a breathing atmosphere. 

Diving Atmospheres (12). The U.S. Navy has conducted research on pressurized breathing atmospheres for many years. 

Knowledge of the Hazards. Adequate knowledge of each of the hazards associated with handling hydrogen in any form allows all needed safety practices to be fully implemented. These hazards have been identified as related to flammability, expansion from liquid to gas in confined spaces, improper materials of construction, cold "burns," and breathing atmospheres con-... 

Between mid-1792 and late 1793 Beddoes published a number of works, which set out the theoretical basis for his plans to develop pneumatic medicine. That basis lay primarily in the notion of regulating the atmosphere, that is, adjusting (in experimental and clinical situations) the amount of oxygen that the breathed atmosphere contained, or at least the amount of oxygen taken in by patients. See, in particular, T. Beddoes, Observations on the Nature and Cure of Calculus, Sea Scurvy, Consumption, Catarrh and Fever Together with Conjectures upon Several other subjects of Physiology... 

Carbon dioxide is a simple asphyxiant that is, it causes toxicity by displacing oxygen from the breathing atmosphere primarily in enclosed spaces and results in hypoxia. It has been postulated that the cause of death in breathing high concentration of carbon dioxide is due to carbon dioxide poisoning and not hypoxia based on a study performed in dogs. 

Important other applications of zeolites in this area include CO2 removal in the breathing atmosphere in space, and recycling of wastewater. Recently the NASA conducted research on the removal of gas components under ultra clean room conditions in satellite systems, where zeolites can reduce the oulgassing rate inside of instruments and absorb molecules without producing additional particles by themselves. 

Escape Respirators People may work in areas that are free of contaminants. However, a leak in a system may produce dangerous breathing atmospheres. In such situations, escape respirators issued to workers provide protection for the danger for a very short time. Workers have time to leave the contaminated area. Escape respirators are not for general use. There must be sensors to detect and warnings to alert workers to a release of contaminants. 

This eliminates the vapor space but sealing the edge can be a problem. Double seals can help and sometimes a fixed roof is also added above the floating roof to help capture any leaks from the seal. However in this case, the space between the fixed and floating roof now breathes and an inert gas purge of this space would typically be used. The inert gas would be vented to atmosphere after treatment. 

Flexible membrane. Another method to stop the vapor space breathing to atmosphere is to use a tank with a flexible membrane in the roof, Fig. 9.26. 

The narcotic potency and solubiUty in oHve oil of several metabohcaHy inert gases are Hsted in Table 10. The narcotic potency, ED q, is expressed as the partial pressure of the gas in breathing mixtures requited to produce a certain degree of anesthesia in 50% of the test animals. The solubiUties are expressed as Bunsen coefficients, the volume of atmospheric pressure gas dissolved by an equal volume of Hquid. The Hpid solubiHty of xenon is about the same as that of nitrous oxide, a commonly used light anesthetic, and its narcotic potency is also about the same. As an anesthetic, xenon has the virtues of reasonable potency, nonflammability, chemical inertness, and easy elimination by the body, but its scarcity and great cost preclude its wide use for this purpose (see Anesthetics). 

Human evolution has taken place close to sea level, and humans are physiologically adjusted to the absolute partial pressure of the oxygen at that point, namely 21.2 kPa (159.2 mm Hg), ie, 20.946% of 101.325 kPa (760 mm Hg). However, humans may become acclimatized to life and work at altitudes as high as 2500—4000 m. At the 3000-m level, the atmospheric pressure drops to 70 kPa (523 mm Hg) and the oxygen partial pressure to 14.61 kPa (110 mm Hg), only slightly above the 13.73 kPa (102.9 mm Hg) for the normal oxygen pressure in alveolar air. To compensate, the individual is forced to breathe much more rapidly to increase the ratio of new air to old in the lung mixture. 

Pressure-Vacuum Relief Valves For apphcations involving atmospheric and low-pressure storage tanks, pressure-vacuum relief valves (PVRVs) are used to provide pressure relief. These units combine both a pressure and a vacuum relief valve into a single assembly that mounts on a nozzle on top of the tank and are usually sized to handle the normal in-breathing and out-breathing requirements. For emergency pressure rehef situations (e.g., fire), ERVs are used. API RP 520 and API STD 2000 can be used as references for sizing. 

TABLE 26-25 Effects of Breathing Oxygen-Deficient Atmospheres... 

A receptor is something which is adversely affected by polluted air. A receptor may be a person or animal that breathes the air and whose health may be adversely affected thereby, or whose eyes may be irritated or whose skin made dirty. It may be a tree or plant that dies, or the growth yield or appearance of which is adversely affected. It may be some material such as paper, leather, cloth, metal, stone, or paint that is affected. Some properties of the atmosphere itself, such as its ability to transmit radiant energy, may be affected. Aquatic life in lakes and some soils are adversely affected by acidification via acidic deposition. 

From inhalation at pressures above atmospheric, used in tunnelling or diving, or from breathing apparatus or resuscitation equipment, if the pressure is too high or exposure is prolonged. This may cause symptoms from pain to dyspnoea, disorientation and unconsciousness it may be fatal. 

Atmospheric chemistry influences human health, climate, food production, and through its impact on visibility, our view of the world. Chemicals in the air affect us with each breath we take. Suspended particulate matter that form from gas-phase reactions affect the amount of solar energy reaching the earth s surface. 

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