Enhancement of Radiation Safety in Industrial Cobalt -60 Irradiator During Abnormal Conditions
Keywords:Gamma Irradiator Facility, Nuclear Safety, Wet Storage Irradiator, Cobalt-60, Security Systems.
Enhancement of radiation safety in industrial cobalt -60 irradiator unit is a necessity need to protect working staff and the environment against radiation release by applying radiation safety standards inside and outside industrial during normal and abnormal operating conditions. This could be fulfilled by preventing stacking, falling, and probability broken cobalt-60 radiation capsules which could lead to water contamination inside the storage pool. The water of storage pool is contaminated by broken hot capsule where the radiation source is changed from close radiation source to very dangerous open radiation source. This paper presents a proposed modified design with concrete shielding maze having more than one right – angle bend to maintain radiation prohibitive and to determine the smallest radiation exposure rates at the entrance of maze design with several legs.
High standards of radiation safety are maintained by the proposed design through safe containing water treatment plant (deionizer plant) which is located safely inside the proposed design. Safe steel shielding sliding door is attached with the proposed design and depending on maze idea. Electrical control system (programmable logic safety controller P.L.C) is incorporated with the steel door design; the recirculation pump is located near control panel to maintain radiation safety for operation and control during the probability of radiation contamination for water storage pool by broken hot cobalt -60 capsules. The deionizer system was equipped by an electronic sensor to automatically close or lock the door of the deionizer room and switch off the pump to prevent the discharge of deionizer wastewater to the normal sewage to prevent the public and environment pollution. Monte Carlo calculations have been carried out for the new proposed design that is attached by cobalt-60 industrial irradiator using complex geometry. The threedimensional flux is calculated at different positions from which the gamma volume is monitored for these positions. All radiological measurements in case of normal operation and abnormal operation after the proposed design are safe.