PROCESS RADIATION MONITORING

Nuclear power plants should be fitted with installed radiation measuring systems for monitoring activity concentrations for process fluids and gases. The purpose of these measurements is to detect fuel failures and the leakage of radioactive material from or into a process system. 

Another method of detecting leaks to the secondary systems for PHWRs is to monitor the amount of make-up water supplied to the primary system, since the normal leak rate from the primary system is very small and any 

Treatment systems for radioactive gases as well as treatment systems for liquid and solid waste should be fitted with suitable systems for process radiation monitoring. 

Appropriate means should be provided to allow monitoring of the activity in fluid systems that have a potential for significant radioactive contamination. In addition, means should be provided for the collection of process samples for more detailed analysis in on-site radiochemical laboratories. 

Auxiliary systems that may also become contaminated are  

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There are five safety systems in Lungmen DCIS. They are Reactor Protection System (RPS), Neutron Monitor System (NMS), Process Radiation Monitoring System (PRMS), Containment Monitoring System (CMS), and Engineered Safety Features (ESF). The software development for all these safety systems follows the BTP-14 requirements. Along with the development, the IV V activities are performed. Of the safety systems, RPS, NMS, PRMS and CMS are designed by GE NUMAC, and ESF is sub-contracted by GE to Eaton Corporation. 

The system is intraided to check continuously that the operational radioactive limits coupled with operational activities are sufficient to prevent excess exposure of public and plant pmonnel. It includes the process radiation monitoring system, the effluent radiation monitoring system, and the in-plant area radiation monitoring system. 

The plant building schematic is shown in Fig. III-8. The plant includes instrumentation and control systems a system for heat removal to consumers an auxiliary power supply system and a radiation monitoring system, including process radiation monitoring, dosimetric monitoring, and environmental monitoring. 

Process radiation monitors are used to monitor radioactivity in process systems, like in the primary coolant system and in the purification system. The objective of process monitors is to assure that the radioactive material is not getting out of its barriers (for example failure of fuel elements), and that the purification system has not been saturated, and still has the capability to retain activation products. 

Photobleaching of T. spiralis preparations was performed, as the worms, as well as cytoplasm of nurse cells, emit a strong autofluorescence. In order to reduce it, the corresponding samples, protected against UV, were exposed to solar radiation for over 2 weeks. The process was monitored by confocal microscopy. 

Area radiological control technicians monitor the fixed radiation monitor systems and use portable hand held gamma monitors to verify that safe conditions exist at key points in the process. ... 

The.radiation monitoring system provides effective monitoring of process discharges and airborne contamination. The process and effluent radiological monitoring and sampling subsystem provides radiation monitoring for the four functions listed below. Individual monitors may provide functionality in more than one of these functions. 

The radiation monitors associated witii the steam generator blowdown system provide a means of recognising when the secondary side becomes radioactively contaminated, an indication of a steam generator tube mpture. The blowdown flow and the ion exchange waste stream (brine) flow are both continuously monitored for radioactivity. If such radioactivity is detected, the liquid radwaste system is aligned to process the blowdown and ion-exchange waste effluent. If radioactivity should exceed a preset level, the blowdown flow control valves and the isolation valves would automatically close. 

The RMS provides plant effluent monitoring, process and fluid monitoring, airborne monitoring, and continuous indication of the radiation environment in plant areas where such information is required. Radiation monitors that have a function important to safety are qualified environmentally, seismically, or both and conform to separation and fire protection criteria. 

Fluid process, airborne, liquid and gaseous radiation monitors include ... 

Application of photodegradation processes for monitoring solar ultraviolet radiation... 

Various steps involved in the processing and display of radiation monitoring signals by the computer are described in the following sections. 

Radiation monitors are divided into three main categories area monitors, air monitors and process monitors. 

The radiation monitoring system was designed to allow continuous monitoration of radiation levels inside the critical facility. It is composed by 27 radiation monitoring channels, being 14 area monitors, 8 process monitors, 3 air monitors, 1 hand and foot monitor and 1 monitor of the "portal" type. 

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