ASTM E2445_E2445M-20 - Standard Practice for Performance Evaluation and Long-Term Stability of Computed Radiography Systems
Standard Practice for Performance Evaluation and Long-Term Stability of Computed Radiography Systems
| Standard number: | ASTM E2445_E2445M-20 |
| Released: | 15.06.2020 |
| Status: | Active |
| Pages: | 21 |
| Section: | 03.04 |
| Keywords: | basic spatial resolution; burn-in; central beam alignment; contrast sensitivity; CR phantom; EPS; erasure; geometric distortion; imaging plate artifacts; imaging plate fading; laser beam scan line integrity; laser jitter; PMT non-linearity; scan column dropout; scanner slippage; spatial linearity; |
1.1 This practice describes the evaluation of Computed Radiography (CR) systems for industrial radiography. It is intended to ensure that the evaluation of image quality, as far as this is influenced by the CR system, meets the needs of users of this standard, and their customers, and enables process control and long-term stability of the CR system.
1.2 This practice specifies the fundamental parameters of CR systems to be measured to determine baseline performance, and to track the long term stability of the system. These tests are for applications up to 320 kV. When greater than 320 kV or when a gamma source is used, these tests may still be used to characterize a system, but may need to be modified as agreed between the user and cognizant engineering organization (CEO).
1.3 The CR system performance tests specified in this practice shall be completed upon acceptance of the system from the manufacturer and at intervals specified in this practice to monitor long term stability of the system. The intent of these tests is to monitor the system performance degradation and to identify when an action needs to be taken when the system degrades by a certain level.
1.4 The use of gauges provided in this standard is mandatory for each test. In the event these tests or gauges are not sufficient, the user, in coordination with the CEO shall develop additional or modified tests, test objects, gauges, or image quality indicators to evaluate the CR system. Acceptance levels for these ALTERNATE tests shall be determined by agreement between the user and CEO.
1.5 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.