Radiation environmental conditions during

ROMP item WISR-35 requires replacement of bearing, grease, and fan belts for the ventilation fans with more temperature- and radiation-tolerant equipment. WISR-35 also requires replacement of fan motor insulation with a more temperature-tolerant winding and modification of the motor protection circuit to install more temperature-tolerant breaker trips. The staff cannot assess the adequacy of these upgrades until the system s environmental conditions during and after design basis accidents are provided. This is an open Item. 

Polymers, during fabrication or storage or in service, may be exposed, sometimes for long periods, to the separate or combined effects of moderate or high temperatures, ultraviolet radiation, and air or other potential oxidants. Under these environmental conditions, polymers are susceptible to thermal, UV, and/or oxidative degradative reactions initiated, in most cases, by the generation of free radicals. Polymer stabilization, therefore, involves incorporation of antioxidants and thermal and UV stabilizers to minimize, if not avoid, such degradative reactions. 

During the course of this program, experimental studies were conducted to identify a number of polymer types in formulations which can be cured via radiation for adhesive applications. Performance studies were also made to determine endurance to exposures of various environmental conditions including moisture, solvents and high temperature aging. Data have been developed on a number of good candidate materials from both commercially available products and laboratory experimental... 

Maximum normal operating pressure shall mean the maximum pressure above atmospheric pressure at mean sea-level that would develop in the containment system in a period of one year under the conditions of temperature and solar radiation corresponding to environmental conditions in the absence of venting, external cooling by an ancillary system, or operational controls during transport. 

Normal operating environmental conditions - those conditions existing during routine plant operations for whieh the equipment is expected to be available on a continuous basis to perform required functions. This includes consideration of radiation effects. 

For instance, a survey through mailed questionnaires has been carried out by INKS in 1984 on the anomalies stated during industrial operations of 362 robots installed in France (4). According to the received answers, the amount of robots working near devices able to generate radiated electromagnetic interferences appears to be 9 % Frequent interferences in the power supplies alone are observed for 23 % of the robotic systems. From the general point of view of environmental conditions (i.e. EMI included), their influence on the robot behaviour is recorded in 31 % of cases, with occurrence of malfunctions (71 % of these cases), of data losses (42 ), and of other failures like breakdown of components (35 %) ... 

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