Disinfection atmosphere

To prevent contact with oxygen, the beer in the pressure tanks is exposed only to a carbon dioxide atmosphere. The pressure must be higher than the saturation pressure for carbon dioxide. Infection in the brewery is prevented by daily cleaning and disinfection of all equipment in contact with the beer. In the past, almost all the beer left the brewery in kegs, but today most beer is bottled or caimed. The ratio is different from country to country. The growing share of beer in bottles or cans has provided a great need for filling machines with capacities of up to 100,000 bottles or cans per hour. 

To remain safe and efficacious on the eye, contact lenses must maintain clear and wetted surfaces, provide an adequate supply of atmospheric oxygen to and adequate expulsion of carbon dioxide from the cornea, allow adequate flow of the eye s tear fluid, and avoid excessive abrasion of the ocular surface or eyeflds, all under a variety of environmental conditions. The clinical performance of a contact lens is controlled by the nature of the lens material the lens design the method and quaUty of manufacture the lens parameters or specifications prescribed by the practitioner and the cleaning, disinfection, and wearing procedures used by the patient. 

Cooling towers and evaporative condensers release into the atmosphere fine droplets of water, which may carry sources of contamination such as algae and bacteria. Many of these thrive at the temperatures to be expected in water cooling systems and one of them, Legionella pneumophila, has been identified as a particular hazard to health. Cooling apparatus should be cleaned and disinfected frequently to reduce these risks of contamination and should not be located where water droplets can be drawn into ventilation air intakes. 

Sulfur dioxide is an economically important gas that is used as a refrigerant, disinfectant, and reducing atmosphere for preserving food. Although it is also used in the manufacture of many other sulfur compounds, the most important use of S02 is as a precursor in producing sulfuric acid. It can be obtained by burning sulfur, but it is also produced in numerous other reactions. Sulfites react with acids by liberating so2. 

Table 16.5 Atmospheric oxidation and chemical hydrolysis of selected antiseptics and disinfectants, estimated by AOPWIN and HYDROWIN from EPI Suite.

The enormous quantity of research that has been done on environmental effects of ozone reflects its importance in atmospheric chemistry, disinfection, bleaching, and advanced technologies for wastewater treatment (47). 

As is usual in the ease of odoriferous disinfectants, there is always a danger of confusing disinfectant or bactericidal action with the mere masking of an unpleasant smell,4 and the actual value of the ozone treatment for stuffy atmospheres is easily over-estimated. 

They are used for chemical synthesis, water and waste treatment, disinfection, neutralizations, and the like. They can also be produced in atmospheric photochemical reactions and as undesirable products, for example, in the combustion of fuels and industrial processes. The most important inorganic gases are ammonia, carbon oxides, nitrogen oxides, ozone and sulfur oxides. 

Ozone is a powerful oxidizing agent. In the atmosphere near the surface of the Earth, it is irritating and injurious in concentrations greater than two parts per million. It can be used as a disinfectant and a bleach. 

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