Main Control Room Emergency Habitability System

VES Main Control Room Emergency Habitability System... 

Main control room emergency habitability system air storage cylinders (though these air cylinders are housed in the radiological auxihary building, they are included within the containment/shield building fire area). 

The Main Control Room Emergency Habitability System (VES) / Control Support Area (CSA) are designed so that the occupants of the MCR are protected against external smoke. 

Maintains the main control room emergency habitability system passive cooling heat sink below its initial design ambient air temperature limit. 

Isolates the HVAC penetrations in the main control room boundary on high-high particulate or iodine concentrations in the main control room supply air, or when the pressurizer pressure falls below the low setpoint, or on extended loss of ac power to support operation of the main control room emergency habitability system. 

Main control room emergency habitability system. 

Main control room supply air duct radiation monitors. These monitors measure the concentration of radioactive materials in the air that is supplied to the main control room. The monitors initiate the supplemental air filtration system on high gaseous concentration and to isolate the air intake and exhaust ducts and activate the main control room emergency habitability system on high particulate or iodine concentrations. Alarms are provided in the main control room. 

In the original design of all WWER plants, the Main Control Room (MCR) and the Emergency Control Room (ECR) do not have their own separate independent ventilation systems which would ensure habitability in an emergency case. The main air ducts for MCR and ECR air supply are not provided with smoke detectors, the signal of which would be used to cut off the ventilation system. 

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