Relative ventilation efficiency

Relative ventilation efficiency A quantity describing how the collection efficiency of a ventilation system varies between different parts of an enclosure. 

Local extract is used to remove contaminants directly from a process to the exterior without passing through personnel breathing zones. It thus provides a high degree of safety and because small volumes of air are extracted relative to a dilution ventilation system it is energy efficient. 

The largest volume of radioactive waste is made up of the ventilation air from processes, plants, and laboratories. However, the quantity of radioactivity is relatively low. It generally occurs in a particulate form readily removed by dry filters. A special class of paper filters developed for this purpose (HEPA or High Efficiency Particulate Air) removes 99.97 percent of 0.3-micron particles. These filters frequently are preceded by scrubbers, sorbers, and roughing filters to extend the life of the paper filter. 

In some studies, the relationship between uptake efficiency and the ventilation rate has been demonstrated [51]. Under hypoxic conditions, rainbow trout increased their ventilation volume which resulted in a higher uptake rate constant for a hydrophobic chemical, since the uptake efficiency remained constant. At very high ventilation rates, however, the uptake efficiency decreased with increasing ventilation flow, which resulted in a constant uptake rate constant at high ventilation rate [51]. It was shown later that ventilation rate related uptake rate constants were only found for relatively large fish of 5-10 g or more, while uptake rate constants were independent of flow rate for smaller fish [52-54]. 

Because the first-formed outer boundary of replacements Arc AC is relatively coarse. After the initial spraying, in order to improve the efficiency of ventilation, some modifications should be carried out to make the Arc AC more smoothly. 

Although relatively efficient, the heat generated from these transformers has resulted in complex ventilation and cooling equipment requirements to cool the transformer room. Transformers designed for outdoor installation or hquid cooled transformers designed to be part of the coohng system for the motors and drives should be considered. 

Fig. 4. Model of the relative contribution of sediment ingestion and ventilation routes of uptake to tissue burden for a filter-feeding bivalve. Response variable is the percentage of tissue concentration that would result from water exposure based on a filtration rate of 72 L d" and an ingestion rate of 0.57 g suspended sediment d". Each curve is a combination of percentage uptake efficiency from ventilation (first legend value) and sediment ingestion (second value). For example, 100-1 means that animals assimilated 100% of chemical from ventilatory activity and 1% of ingested chemical.

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