12,Iodine radiation monitoring

Figure 17.6 a. Radioactive iodine molecules in the solid in the flask on the right are separated from nonradioactive iodine in the flask on the left. Note the readings on the radiation monitors, b. After the stopcock has been open for a time, the radiation monitors show that radioactive molecules are in both flasks. The particles must have moved back and forth between the flasks and between the solid and the gaseous phases. 

In Containment postaccident air sampling and on-line radiation monitoring with speciation with speciation global dose rate global dose rate gaseous iodine iodine activity iodine activity Yes (1) Yes (2)... 

Airborne radiation monitors are described in CESSAR-DC Section 11.5.1.2.4, and include a portable unit that can be moved to areas where work or surveillance activities are at an unusual risk of airborne exposure. This monitor includes detector channels for particulate, iodine, and gaseous activity. All equipment is assembled on a mobile cart, and the design allows for transfer of the particulate sample filters and iodine sample cartridges to the Station Counting Room for further sample analysis. 

Equipment for continuous sampling during and after an accident of plant gaseous effluent for noble gases, iodine and particulates, and for radiation monitoring of areas requiring post-accident access is as follows ... 

Since the RMS includes (a) a portable airborne iodine monitor, (b) continuous post accident gaseous effluent monitoring for noble gases, iodine and particulates, (c) containment high radiation monitors, (d) radiation monitors for areas requiring post-accident access to safety equipment, and (e) control room readouts and annunciation, this issue is resolved for the System 80+ Standard Design. 

At all stages of medical care, the treatment of highly contaminated individuals will require special facilities or isolated facilities with the specif procedures that limit the spread of contamination and disposal of contaminated waste. For the deteetion of radioaetive eontam-ination, radiation equipment should be available, such as specialized radiation monitoring instruments, whole body counter, and iodine thyroid counter. Usually a radiation protection officer or health physicist performs the measurements. For the purpose of dose reeonstraction, different instruments and methods can be used, such as electronic paramagnetic resonance (EPR) spectrometry and cytogenetic dosimetry. Because of this, collection of various tissues (blood, hair, and teeth) and clothes of exposed persons should be organized. Provisions (plastic bags, labels, etc.) should be made in advance. 

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. 

The nuclear explosions that devastated Hiroshima and Nagasaki killed 100,000 to 200,000 people instantaneously. Probably an equal number died later, victims of the radiation released in those explosions. Millions of people were exposed to the radioactivity released by the accident at the Chernobyl nuclear power plant. The full health effects of that accident may never be known, but 31 people died of radiation sickness within a few weeks of the accident, and more than 2000 people have developed thyroid cancer through exposure to radioactive iodine released in the accident. Even low levels of radiation can cause health problems. For this reason, workers in facilities that use radioisotopes monitor their exposure to radiation continually, and they must be rotated to other duties if their total exposure exceeds prescribed levels. 

We have been impressed with the favorable radiation safety aspects of the GO-LPO iodination technique. Since we have been using this technique, personnel monitoring for radiation contamination both by bioassay (thyroid counts) and by dosimeter readings have not been above background (NAB). 

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