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Deep underground laboratories are multidisciplinary research infrastructures. The main feature of these laboratories is the reduced cosmic ray muons flux. This characteristic allows searching for rare events such as proton decay, dark matter particles or neutrino interactions. However, biology in extreme environments and geophysics are also studied underground. A number of ancillary facilities are critical to properly operate low background experiments in these laboratories. In this work we review the main characteristics of deep underground laboratories and discuss a few of the low background facilities.

Nano silicon with $80{\mathrm{\text{m}}}^2{\mathrm{\text{g}}}^{-1}$ specific surface area, 100 nm size and 0.08 g/cm³ density has been irradiated continuously with neutrons $(2\times 10^{13}\mathrm{\text{n}}\cdot {\mathrm{\text{cm}}}^{-2}{\mathrm{\text{s}}}^{-1})$ up to 20 h at various periods in TRIGA Mark II type research reactor. After the neutron irradiation, cooling time of the samples is taken approximately 360 h. It is found that the initial radioactivity of the irradiated samples changes within 0.1 kBq–3.1 GBq range. Definition of elements’ concentration is determined based on the activities formed in the relevant energy range. After the irradiation, the result of activity analysis carried out the element content of 1% mixture existing in nano Si which has been defined with radionuclides of the relevant element. Moreover, from activities of mixed radioisotopes, their amounts in percentage has been determined.

2008 marks the 100th anniversary of Henri Becquerel's death, the discoverer of radioactivity and a leading contributor to the birth of modern physics. In addition to well-deserved celebrations, this offers a chance for a sobering look at scientific dissemination then and now and at the evolution of technology transfer. The facts are shocking: both dissemination and technology transfer were much faster and effective at the time of Becquerel, in spite of all the new communication techniques. I briefly speculate on the causes of these dismal failures, arguing that they are primarily rooted in society, academic management and industrial management — and therefore very difficult to reverse.

The effective liquid drop model (ELDM) is used to explore the one proton radioactivity of all possible Dysprosium isotopes, and the molecular phase of the di-nuclear system is used to investigate the possible barriers limiting one proton emission. The mass excess values are obtained from [Chin. Phys. C45 (2021) 030003]. The WKB integral is used to evaluate the penetration probability. The half-lives of proton decay are compared to those of other decay modes. The decay chains of ${}^{133-135}$Dy are predicted. The detailed investigations of ${}^{133-135}$Dy show proton radioactivity when ${}^{133-135}$Tb is converted to ${}^{132-134}$Gd with the half-life of order of nanoseconds. Further, these identified proton emitters may find to be useful in the field of diagnosis and radiotherapy.

The goal of the SPES project is to produce accelerated radioactive ion beams for Physics studies at “Laboratori Nazionali di Legnaro” (INFN, Italy). This accelerator complex is scheduled to be built by 2016 for an effective operation in 2017. Radioactive species are produced in a uranium carbide target, by the interaction of 200 $\mu$A of protons at 40 MeV. All of the ionized species in the 1+ state come out of the target (ISOL method), and pass through a Wien filter for a first selection and an HMRS (high mass resolution spectrometer). Then they are transported by an electrostatic beam line toward a charge state breeder (where the 1$+$ to n$+$ multi-ionization takes place) before selection and reacceleration at the already existing superconducting linac. The work concerning dose evaluations, activation calculation, and radiation protection constraints related to the transport of the radioactive ion beam (RIB) from the target to the mass separator will be described in this paper. The FLUKA code has been used as tool for those calculations needing Monte Carlo simulations, in particular for the evaluation of the dose rate due to the presence of the radioactive beam in the selection/interaction points. The time evolution of a radionuclide inventory can be computed online with FLUKA for arbitrary irradiation profiles and decay times. The activity evolution is analytically evaluated through the implementation of the Bateman equations. Furthermore, the generation and transport of decay radiation (limited to gamma, beta- and beta$+$ emissions) is possible, referring to a dedicated database of decay emissions using mostly information obtained from NNDC, sometimes supplemented with other data and checked for consistency. When the use of Monte Carlo simulations was not feasible, the Bateman equations, or possible simplifications, have been used directly.

In this paper, we share and discuss findings from our study involving Grades 9–12 Singapore students’ conceptions and perceptions of radiation and radioactivity. The students would have learned in science lessons about electromagnetic waves and the basic atomic structure but had no prior formal classroom lessons on radioactivity and nuclear physics. We found similar alternative conceptions and risk perceptions held by the students as reported in literature. These findings provide useful background knowledge for teachers to consider when developing learning experiences for students in this topic, with the goal to develop a strong foundation in the related key concepts and address risk perception gaps for students to make responsible and informed decisions on scientific and technological applications associated with radiation and radioactivity.

Radioactive contamination of natural and anthropogenic landscapes has become a significant factor in radionuclide uptake by humans since 20^th century. Contamination of soils by radionuclides occurs as a result of nuclear weapon tests, major radiation accidents, waste deposition, and using phosphate fertilizers with a high content of natural radionuclides. Various methods of rehabilitation of radioactively contaminated lands, such as plowing, liming, addition of sorbents, and addition of mineral and organic fertilizers, as well as phytoremediation techniques, have been developed. Among them, elimination of the upper soil layer and phytoremediation allow decreasing the real activity of a soil but generate secondary radioactive waste, whereas the other methods are focused on suppression of radionuclide transfer from soil to plants. Plowing the upper soil layer to deeper horizons and using ferrocyanide sorbents result in the maximum decrease in radionuclide transfer to plants among the developed methods.

Potential biological effects initiated by exposure to ionizing radiation are described in some detail, including the characteristics of radiation sources, radiation fields, dosimetry, and fundamental radiation protection quantities and units. Special attention is paid to exposure pathways and the risk assessment of radiation exposure to the human body in terms of relevant health risks reflecting biological effects resulting from external and internal radiation exposure. Some particulars are presented to illustrate the nature and severity of stochastic and deterministic effects caused by the exposure. The chapter then presents an overview of pertinent radiation protection requirements and monitoring methods for the evaluation of exposure of persons in regular and emergency situations, as well as the assessment of environmental radioactive contamination inflicted by releases of radioactivity from facilities where radioactive materials are used or stored, taking into account their possible damage or destruction resulting from accidents and potential terrorist attacks, sabotage, or other malevolent actions. In all these cases, discharges of radioactive substances from various sources, including those used in medicine, industry, and research facilities, should be considered to obtain reliable information about specific radiation routes. Radioactive materials, in the form of solid particulates, aerosols, and gases, disperse in several ways known as exposure pathways. It is essential that the description of both exposure pathways and their characteristics be expressed in officially recommended and generally accepted quantities and units. In general, the final part of an exposure pathway refers to how a person can come into contact with hazardous substances, including materials containing radionuclides.

Radionuclides are present in the environment or result from human activities, such as the use of radiation or nuclear technologies. The presence of radionuclides in foods can pose certain health risks, and their toxicity depends on several factors, including the intake of radionuclides, the type of radionuclide, its concentration, and the specific characteristics of the food. Under typical situations, the contributions of internal exposure to the human body from food or water, where only trace concentrations of usually natural radionuclides are present, are minor in most cases. Slightly different situations may occur when food, due to radionuclides from man-made sources used in various applications in industry and medicine or radioactivity induced during radiation sterilization of food, shows an increased level compared with the natural background concentrations. But even here, there is no reason to consider the impact on living organisms to be serious since the increase in exposure levels is only a fraction of exposure due to the natural background.

On the other hand, however, the concentration may be higher in some cases when the food is produced from plants or animals that are heavily contaminated. Specific aspects of radioactivity or, in general, ionizing radiation (hereinafter, simply, radiation), which can be detected even at particularly small levels thanks to the availability of very sensitive instrumentation, have to be stressed here. Radiation monitors are able to measure even extremely insignificant changes within the fluctuation level of natural radiation. When the instrument shows some results close to the background level or even up to several times this level, there is no need to be concerned since the impact of such exposure on a person is almost negligible in comparison with other, much more dangerous situations we face daily in our typical living or working environment caused by many other, much more hazardous agents. The chapter will present an overview of the health risks attributed to the toxicity resulting from exposure to foods contaminated by radionuclides of various origins.

Using an activation calculation code FDKR and its associated data library AF-DCDLIB to calculate the radioactivity, decay heat, waste disposal rating and biological hazard potential from activation products, actinides and fission products in the FEB-E. The codes and libraries used in calculation are introduced briefly, and calculation results and decay curves of related hazards after the shutdown of one-year operation of the FEB-E are given. Results obtained show that the total radioactivity inventory, decay heat and BHP at shutdown are 5.74 × 10¹³MBq, 8.34MW and 4.08 × 10⁸km³ of air for 316SS structure material, respectively.

An experiment carried out at the RIKEN Nishina Center with the BigRIPS fragment separator allowed us to observe ⁶⁷Kr for the first time and its two-proton radioactivity (2P). This is just the fourth 2P ground-state emitter observed. It has a half-life of some ms. We measured a decay energy of 1690(17) keV, a 2P branching ratio of 37(14) % and a half-life of 7.4(30) ms. No evidence of 2P radioactivity was seen for the other candidates predicted by theory: ⁵⁹Ge and ⁶³Se.

The proposal EXPERT is suggested for the Super-FRS Collaboration physics program [1] in the NUSTAR Collaboration of the project FAIR (Facility for Antiproton and Ion Research) in Darmstadt, Germany. It is aimed at studies of the nuclear landscape beyond the proton and neutron drip-lines and intends to push researches up to limits of nuclear existence. By combining the EXPERT instrumentation (two tracking techniques applied for radioactivity and nuclear decays in-flight), the phenomena of multi-nucleon radioactivity, resonance decays in continuum, beta-delayed exotic decays and exotic excitation modes can be studied via observations of particle emissions, including the 2p, 4p, 6p, n, 2n, 4n, 6n channels.