Ventilation methods

Select the optimal ventilation method to reduce emissions and/or to pro tect workers. (For details, see the subtree Fig.. 3.10.)... 

Zhivov, A. M. 1992. Selection of general ventilation method for industrial spaces. Presented at 1992 annual ASHRAE meeting ( Supply air systems for industrial facilities seminar). 

Other types of local ventilation methods include elephant trunks and free-hanging canopies and plenums. The elephant trunk is simply a flexible vent duct that is positioned near a source of contaminant. It is most frequently used for loading and unloading toxic materials from drums and vessels. Free-hanging canopies and plenums can be either fixed in position or attached to a flexible duct to enable movement. These methods will most likely expose workers to toxicants, but in diluted amounts. 

This is interesting as an early record of methods of recognition of the danger from carbon dioxide and a method for safeguarding the workers. Empirical knowledge of ventilation methods in mines was doubtless of very ancient origin, because of the mining experience of the ancients. 

Since the air flowrate for dilution ventilation is approximately 2000 times higher than the local ventilation air flowrate requirement, and considering the high cost of large blowers to handle high air flowrates, the local ventilation method is the better method for this case. 

Preparation, ventilation, and cleaning procedures for stationary petroleum and petrochemical storage tanks. Tank cleaning, permits, ventilation methods, tank entry, flammability and toxicity hazards, and special considerations for tank design and contents. 

Using exhaust ventilation methods and increasing the air volume in order to increase the oxygen volume supply into the mine as Major measures, at same time, Depend on the personnel training and selection as auxiliary measures to improve mine production environment. 

The program 1 has three advantages. (Dexhaust ventilation methods Due to less external leakage, therefore the mine ventilation is easy to manage. it is no need to set the ventilation structures in the main air routes, so ventilation resistance is small and easy to transport. if the main fan stops for any reason, the airflow pressure will increase in underground, which can inhibit the gas emission and is of help gas management, so the mine is relatively safe. 

The program 2 has three disadvantages. Because of using exhaust Ventilation methods, it have the same disadvantages with the program 1. The establishment of pressure chamber in face crossheading lead to the transportation inconvenience and economy unreasonable. The air pressure has no change in other locations. 

Program setting of program 3 as follows It uses the forced ventilation method and artificial pressurization techniques to improve air pressure pro-... 

Numerical simulation has been adopted to analyze the impact of local ventilation methods. Figure 2 and Figure 3 show the distribution of airflow in tunneling roadways respectively with forced ventilation and withi aw-able ventilation, where the roadway had a length of 100 m and a height of 2.4 m the diameter of air duct was 0.4 and the distance from air duct outlet to tunneling end face was set to 5 m. 

There are numerous standards that set exposure limits that may rely on ventilation systems for the protection of workers, building occupants, and others. Other chapters have covered exposure standards and protection from other hazards. There are few standards that address ventilation methods, systems, and design. The Bibliography for this chapter lists references on ventilation technology and system planning and design. 

While it is difficult to predict the future based upon current trends, making products smaller, hghter, faster, more energy efficient, and less expensive will continue. With these trends will be the requirement to channel the heat away from components. One recent development in 2004 was the Perdue University announcement of a patented technique of a self-ventilating method where microfluidic-like layers pump... 

Ventilation techniques vary depending on the size and type of the industry you work in. Some large facilities use sophisticated industrial exhaust systems like state-of-the-art electrostatic precipitators. Very often, however, a relatively simple ventilation method like the appropriate use of wall fans will be all that is required to provide good ventilation during welding operations. 

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