UNDERSTANDING AND ADDRESSING EQUIPMENT LIMITATIONS THROUGH TESTING

Safeguards demands have brought about the use of new, advanced equipment. These new systems are typically more complex than previous systems, sometimes making use of dense circuitry and complex controls that can bring out previously unseen susceptibilities to various environmental conditions. In addition to possibly being susceptible to ambient conditions such as temperature and humidity, there may be a misunderstanding regarding the operational limitations of the equipment. Will a radiation detector respond to a moving source? Will other types of radiation overwhelm the response of the detector to the radiation of interest? Will the electronics survive or become incapacitated after exposure to radiation? These questions and others need to be addressed through the use of a systematic testing program. The program should not be used as a tool for criticism, but as a method of improving the reliability of equipment in the field and as a technique for improving the operation of the equipment. This document presents some of the information that was obtained at Oak Ridge National Laboratory (ORNL) where a series of tests were performed on various types of equipment with differing functions. Equipment tested included data transmission devices and radiation sensors. Tests performed included ionizing radiation to test for effects from interfering radiation and as a characterization tool for such things as response to moving sources. Other tests involved the use of nonionizing radiation to determine whether interference could occur when equipment is exposed to radio frequency or magnetic field environments. The remaining tests were performed to establish whether susceptibilities exist when equipment is exposed to various temperature and humidity environments. Although more testing may be needed, the test methodologies used could provide a direction to future qualification plans.