Target airflow

The main target levels inside a building are normally set for temperature, humidity, air velocity, airflow rate (and air distribution), and contaminant concentration.1 -... 

The influence of the building on the ventilation system, and indirectly on the target levels, can take many forms. There are, e.g., emissions from the materials that demand increased airflow rates and also door and window open-... 

For nonenclosing hoods, the airflow rate that allows contaminant capture is called a target airfloitO The target airflow rate is proportional to some characteristic flow rate Qg that depends on the type of contaminant source ... 

FIGURE 7.81 Hood performance for different exhaust airflow rates, (a) Target airflow rate q (b) Target airflow rate q < q. (c) Target airflow rate q > q. ... 

To give the designer some advice, many recommendations exist in literature. Some general recommendations can be found in prEN 13779 for designing the air distribution system for low energy consumption. These include giving a certain target level for power consumption [the so-called SEP class. SEP means specific fan power, the ratio between the input power of fan mo tors and the total airflow, in W/(m s" )]. 

Columri 6(J cm X 6 mm, CIS Coraai], target, gold, mobile phase water at 54 ml/min., airflow 4.130 ml/roLn. 

While the removal of airborne contaminants by the nose is effective, this action also renders this organ susceptible to toxic damage. The behavior of the inhaled substances in the NP airways and the ultimate determination of whether they are deposited or exhaled depends on numerous factors for example, breathing patterns that influence nasal airflow rates and the chemical and physical properties of the airborne material, such as size, shape, water solubility, and reactivity. Soluble particles may, once deposited, rapidly enter the blood circulation and be transported systemically. Thus, the effective dose of toxicant delivered to the target tissue depends on factors other than the environmental concentration. 

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