Exhaust hood receiving

The main condenser is designed to receive and condense the full-load main steamflow exhausted from the main turbine. It also receives discharges from auxiliary systems such as the feed water heater vents and drains and the gland sealing steam spillover and drains. To protect the condenser shells and turbine exhaust hoods from overpressurisation, steam relief blowout diaphragms are provided in the low-pressure turbine exhaust hoods. Two low-pressure feedwater heaters are located in the neck area of each condenser shell, adjacent to where their steam is bled from the low-pressure turbine. 

Receptor hoods, also called canopy hoods, are designed to capture contaminants given off by heated processes. They take advantage of the thermal updraft caused by such processes by placing the hood in the path of the updraft, they receive the exhaust and capture the contaminants. 

The blower system incorporates a variable-speed motor, battery, external power-supply cable, housing assembly, control switch, chemical-biological canister, and a means of securing the blower while the crew member is mobile. The mask receives filtered air from the blower unit, which also allows overpressure within the hood which defogs the lens and is vented through an exhaust valve. 

Written records should be maintained of the amounts involved in each of these processes, and it should be possible to account fornearly aUofthe material from the time it is received until disposedofas waste. Some uncertainty is certain to be introduced during actual experimentation, especially if there is a gaseous metabolic or combustion product released through the exhaust from a hood. There also will be small quantities that will be retained on the interior of vessels containing radioactive liquids that wUl escape into the sanitary system when the container is washed. However, it should be possible to estimate these types of losses with reasonable accuracy. 

A local exhaust system is used to collect air contaminants at the source, as contrasted with general ventilation, which allows the contaminant to spread throughout the workroom, later to be diluted by exhausting quantities of air from the room. Local exhaust may be achieved using an enclosure, a receiving hood, or an exterior hood. Exhaust Ventilation... 

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