ASTM C1233-15R21
Standard Practice for Determining Equivalent Boron Contents of Nuclear Materials
| Označení normy: | ASTM C1233-15R21 |
| Vydáno: | 01.10.2021 |
| Status: | Active |
| Počet stran: | 3 |
| Sekce: | 12.01 |
| Označení: | boron; neutron absorption; nuclear materials; nuclear poisons ; |
| ASTM označení: | ASTM C1233 |
| Nahrazuje: | C1233-15 |
This practice details the recommended method for calculating the equivalent boron content (EBC) values of nuclear elements and materials that are of potential significance as thermal neutron poisons. EBC factors are determined from the atomic weight of elements and the thermal neutron absorption cross section in barns. These may be used depending upon the actual neutron energy characteristics of the applicable reactor system. The elements aluminum, fluorine, rubidium, barium, lead, silicon, beryllium, neon, tin, bismuth, oxygen, zirconium, carbon, magnesium, cerium, and phosphorus are not required to be included in the EBC calculations as their contribution to the total poison effect is not considerably significant.
1.1 This standard details a recommended practice for the calculation of the Equivalent Boron Content (EBC) for nuclear materials. The EBC is used to provide a measure of the macroscopic neutron absorption cross section of a nuclear material. EBC factors for the natural elements are determined from their atomic masses and thermal neutron absorption cross sections. This practice is illustrated by using EBC factors that are based on thermal neutron (2200 m/s) absorption cross sections. Other EBC factors may be used depending upon the actual neutron energy spectrum.
1.2 The EBC is a characteristic of a homogeneous material. Characterization of inhomogeneous materials and calculation of neutron multiplication factors require techniques that are beyond the scope of this practice.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 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.