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Applied Chemistry and Physics
Published in Robert A. Burke, Applied Chemistry and Physics, 2020
Beta particles are negatively charged and smaller, travel faster and penetrate farther than alpha particles. A beta particle is 1/1,800 the size of a proton or roughly equal to an electron in mass. Beta particles will penetrate the skin and travel from 3 to 100 ft. Full turnouts and SCBAs will not provide full protection from beta particles. Particulate radiation results in contamination of personnel and equipment where the particles come to rest. Electromagnetic energy waves, like gamma particles, do not cause contamination.
Terms and Definitions
Published in Rick Houghton, William Bennett, Emergency Characterization of Unknown Materials, 2020
Rick Houghton, William Bennett
Alpha particles consist of two protons and two neutrons and are about 7,000 times more massive than a beta particle. The increased mass means alpha particle radiation can be stopped by a sheet of paper or the dead layer of skin cells on a human. Comparatively, alpha particle radiation is not much of a hazard to the skin, but there are serious inhalation, ingestion, and injection hazards. Epithelial cells that line the respiratory and gastrointestinal tract have no dead layer of cells for protection. A radioisotope dust that is swallowed or inhaled will settle directly on live cells and cause local irradiation injury. The same type of injury can occur with eye contact. Because alpha particles are large and prone to collision while delivering energy over a short distance, they have potential to cause severe biological damage. Alpha radiation can only travel a few centimeters through air. Alpha particles are emitted from substances such as plutonium, radon, and radium.
Area Monitoring and Contingency Planning
Published in Martha J. Boss, Dennis W. Day, Air Sampling and Industrial Hygiene Engineering, 2020
A nucleus with a slightly unstable ratio of neutrons to protons may decay through the emission of a high-speed electron called a beta particle. This emission results in a net increase of one unit of atomic number (Z). The beta particles emitted by a specific radionuclide range in energy from near zero up to a maximum value characteristic of the particular transformation.
The Effect of Intrinsic Radiation from a 3 × 3-in. LaBr3(Ce) Scintillation Detector on In Situ Artificial Radiation Measurements
Published in Nuclear Technology, 2018
Li Sangang, Cheng Yi, Wang Lei, Yang Li, Liu Huan, Liao Jiawei, Zeng Liyang, Luo Yong, Wang Xiaoyu, Pei Qiuyan, Wang Jie
As shown in Fig. 4, 138La decays by electron capture (EC) (66.4%) to 138Ba and by beta-minus (β−) decay (33.6%) to 138Ce. During the EC decay process of 138La to 138Ba, a gamma ray of 1435.8 keV (100%) and an X-ray at 34.7 keV are produced for the K-atomic shell or at 5.6 keV for the L-atomic shell. Furthermore, the gamma ray of 1435.8 keV creates a Compton scattered photon in the LaBr3(Ce). The Compton scattered events are partly in the relatively flat region of the Compton continuum in the spectrum.9 In addition, the gamma ray of 1435.8 keV and the X-ray are added together and create another peak that can affect the measurement of 40K. In the β− decay process, one beta particle, one gamma ray, and one antineutrino are emitted. The beta particle energy can have any value from zero to the end point energy of 255.11 keV. The gamma ray has an energy of 788.7 keV (100%) (Ref. 13).
Managing hazardous materials in New Zealand’s National Petrology Reference collection
Published in New Zealand Journal of Geology and Geophysics, 2018
Delia T. Strong, Rose E. Turnbull, Andreas Markwitz
Total radiation dose is made up of neutrons, alpha- and beta-particle exposure, and gamma-ray exposure plus, for example, contamination by radon and other daughter gases (Lambert 1994) which can build to dangerous levels in confined and poorly ventilated spaces (Freedman 2011). Alpha and beta particles attenuate or reduce in strength readily and are not considered hazardous in totally passive and secured geological collection storage situations (Henderson 1982), whereas exposure to penetrating gamma-rays may be hazardous to human health (Mast 1996). Neutrons have an even wider range of exposure and can only be stopped by shielding with lead and/or thick concrete walls. There is human health risk from alpha, beta and gamma sources in close exposure situations where rocks are actively extracted from drawers. This risk is posed by inhalation, ingestion and absorption through the skin of fine particles of radioactive material, for example, from friable rock samples, and bombardment of the body by penetrating radiation due to proximity to the samples.
Assessment of Radiation Background Suppression Using Phoswich Detectors for In Vivo Pb-210 Measurements: A Simulation Study
Published in Nuclear Technology, 2022
Xiangpeng Meng, Yuanyuan Liu, Bin Wu, Jianping Cheng, Li Wang, Yu Wang, Ning Su
The stark contrast between the 1.46-MeV gamma-ray–led background and the 1.33-MeV beta-particle–led background is evident. The anticoincidence mode exhibits an appreciable effect in reducing the 1.46-MeV gamma-ray–led background whereas this method is highly inefficient for suppressing the 1.33-MeV beta-particle–led background. We derived the counts inside the ROI originating from the 1.46-MeV gamma rays and the 1.31-MeV beta particles and calculated their ratio. This ratio increases from 1:3 to 1:5 after the anticoincidence mode is activated, thereby further enhancing the dominance of the beta-particle–led background.