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A closed container having a specified quantity of ²²⁶Ra was constructed as encapsulated ²²⁶Ra–²²²Rn source. The source in the form of a modified Lucas cell (LC) was used for standardization of Lucas cell alpha counting system. The performance of the prepared source was evaluated by simultaneous measurement of dissolved radon in water by Lucas cell method using alpha counting system and Alpha guard. Radon alpha counting system measures dissolved radon in water sample by gross alpha counting of aerated dissolved transferred to LC. The same samples were also measured simultaneously by Alpha guard using instant measurement of emanated radon in a closed circuit. The gross alpha counting method using the radon counting system produced result that is closely matching with the Alpha guard measurement. This validates the calibration of radon counting system by designed encapsulated source. The study provides an alternative for calibration in the absence of expensive radon source available in the market.

Gases from the breath exhalation can be used for the detection and estimation of associated contaminant in the human body. For the estimation of ²²⁶Ra body burden through the analyses of radon (²²²Rn) in the exhaled breath, similar technique has been considered for uranium miners in India. Initial experiments for Jaduguda underground uranium mine workers were based on qualitative approach due to the limitations of the sensitivity of the then available techniques. The inert gas ²²²Rn after its formation is soluble in the blood, may escape from the human body like other dissolved gases at lung/blood interface which can be removed through exhalation. Using a sensitive device that can effectively analyze the low activity concentration of radon, ²²⁶Ra body burden of the uranium miner can be estimated. The working principle, description and utility of the device as well as estimated ²²⁶Ra body burden are provided in the paper. Examination results of 244 subjects of uranium mines have shown a variation in the radium (²²⁶Ra) body burden from 0.54 to 3.75 kBq. The inexpensive technique can effectively be used in the field conditions due to high sensitivity, portability, low sampling time and minimal instrumentation requirements.

The feasibility study of the uranium mill tailings generated from the Turamdih process plant as a construction material was evaluated by making bricks using the tailings as one of the components of the bricks. Two major techniques, such as moulding and pressing, were used to produce bricks from the tailings. Mill tailings in the bricks varied from 15 to 62% with other materials such as sand, cement, gypsum, lime, bed materials, LD slag, fly ash, and aggregates. The major qualifying criteria, such as compressive strength, water absorption, leaching test, and ²²²Rn exhalation rate, were estimated using the standard methods to assess the suitability of the bricks for use as construction material. Three types of qualified bricks with different tailings compositions (30%, 40% and 50%), along with the other materials in bulk quantities, were produced and used in the model house to evaluate the associated in situ radiological hazards. The in situ mean ²²²Rn exhalation rates from walls were 0.0007 Bq/m²/s, 0.0012 Bq/m²/s, and 0.0021 Bq/m²/s made of tailings bricks with respective tailings compositions of 30, 40, and 50%. The maximum indoor radon concentration likely to be contributed by the 50% tailings bricks was estimated to be less than 20 Bq/m³ for minimum air changes of 0.5 per h. The estimated radium equivalent activity (Ra_eq) indicated that the bricks can be suitably used in industrial buildings, foundations of non-residential buildings, and the construction of roads and bridges without any significant radiological hazards to members of the public.

This study is performed with a dedicated scanning electron microscope (SEM) which allows the injection of few electrons doses in a large domain of energies and the measures of the secondary electron emission and the induced current created in the sample holder by the charges generated in the sample. In this paper, we present a detailed calcul of the precision measure on the intrinsic Secondary Electron Emission yield σ₀ and the stationary electron emission σ_st of magnesium oxide (MgO) single crystals of different crystalline orientation (100), (110) and (111)_. We notice that the precision measure becomes more and more excellent with increasing n (n is the number of equal time intervals Δt in which the measure of the induced and secondary currents is carried). The results shown that the crystalline orientation has a significant influence on intrinsic secondary electron emission σ₀ at low energies below 7 keV, but for high energies, the loss function of energy extending more deeply, the secondaries are dispersed before their release.

In this study, the radiological impact of naturally occurring radionuclides (²³⁸U and ²³²Th) and fallout radionuclide (¹³⁷Cs) in the soil around the Kaiga Generating Station (KGS), Kaiga, on the terrestrial non-human biota was investigated. Through the analysis of 113 soil samples collected from 2015 to 2021, the study determined mean activity concentrations of 2.9 ± 1.4, 19.6 ± 5.2, and 24.1 ± 4.3 Bq kg⁻¹ d.w. for ¹³⁷Cs, ²³⁸U, and ²³²Th, respectively, in surface soil samples. Utilizing the ERICA assessment tool (v2.0) and employing the Tier-2 approach, the study estimated radiological doses to reference organisms in the terrestrial ecosystem around Kaiga. Lichens and bryophytes exhibited the highest activity concentrations for ¹³⁷Cs, ²³⁸U, and ²³²Th, while annelids showed the lowest activity for ¹³⁷Cs, and for ²³⁸U and ²³²Th, amphibians exhibited the minimum activity. The total dose rates (internal + external) ranged from 1.9E−03 to 6.7E−01 µGy h⁻¹. Despite the highest dose rate of 6.7E−01 µGy h⁻¹ observed in lichen and bryophytes, all assessed dose rates remained below the ERICA screening level of 10 µGy h⁻¹. Risk quotient values for all reference organisms were less than 1 (RQ < 1), indicating negligible risk to non-human biota.

The concept of equivalence was formulated to harmonize the different standards developed and maintained by national metrology institutes (NMIs) worldwide. Equivalence of a NMI with other NMIs or designated institute (DIs) is realized through international comparisons. International comparisons ensure the consistency and accuracy of measurements of various radionuclides that are carried out in laboratories worldwide. Organizing key comparisons by CCRI(II) meeting the requirement of NMIs/DIs for various radionuclides is challenging and cumbersome. Consequently, Syst`eme International de R´ef´erence (SIR), a system that enables NMIs to compare measurements standards over a wide spectrum of radionuclides, was approved by Section II of Consultative Committee on Ionising Radiation (CCRI II). Under this SIR intercomparison programme, BARC standardized radioactive solution of ⁶⁰Co by the primary methods using the 4π β-γ coincidence systems which are indigenously developed and maintained at BARC. The degree of equivalence (D_i) of BARC for ⁶⁰Co (BIPM.RI(II)-K1.Co-60) comparison is D_i =  − 13 ± 42 kBq at expanded uncertainty (k = 2). This comparison demonstrates the measurement equivalence for ⁶⁰Co, and inclusion of BARC equivalent activity in KCRV indicates the consistency of the measurements and the standards maintained at BARC. This paper describes the various methods used for standardizing ⁶⁰Co and the results of the comparison.

This paper illustrates the applications of analytical models and machine learning methods to predict the equivalent continuous sound pressure levels (L_Aeq) along with 10-percentile exceeded sound levels (L₁₀) generated due to road traffic noise based on rigorous noise monitoring conducted at more than 200 locations in Delhi-NCR. Using the measured data, regression, back-propagation neural network, and machine learning models were developed, validated, and tested. The work represents that the developed models are suitable for reliable and accurate predictions of hourly traffic noise levels. A comparative study reports that the machine learning-based model outperforms the classical analytical models. Multiple linear regression models and three machine learning techniques, namely decision trees, random forests, and neural networks, were utilized for developing models that predict the hourly equivalent continuous sound pressure level (L_Aeq1h) and 10-percentile exceeded sound pressure level (L₁₀). The developed predicted models have been ascertained to show an accuracy up to ± 3 dB(A). The proposed prediction models in the study can serve as a tool for planning noise abatement measures and traffic noise forecasts for the Delhi-NCR region. This study is the first rigorous study of its kind that covers a larger number of areas and zones in Delhi-NCR for assessment and predictions of road traffic noise and also shows an illustrative example of estimating measurement uncertainty in hourly noise measurements as per ISO 1996-2:2017.

The detection and measurement of radionuclides are indispensable processes, crucially guided by particle and photon emission mechanisms. Regulatory agencies and policymakers demand precise measurements to ensure compliance with safety standards and environmental protection mandates. To convert detection rates into meaningful activity values, certain vital parameters must be derived, necessitating validation through reference measurements, technical innovations, and proficiency testing. Gross alpha activity assessment holds particular significance in both finished products and the waste generated within naturally occurring radioactive materials (NORM) industries. The thickness of the radiation source emerges as a pivotal factor influencing gross alpha activity determination, owing to the energy losses incurred through self-absorption processes. This study endeavors to comprehensively investigate the impact of self-absorption in relation to source thickness, alongside an exploration of the associated procedural considerations. The research encompasses theoretical examinations of the range and stopping power of alpha particles as they interact with the source material itself, complemented by empirical measurements involving sources of varying thicknesses. Specifically, this study examines the influence of source thickness on the measurement of alpha activity within radioactive waste materials, originating from front-end nuclear facilities. In the context of this study, liquid wastes arise during the ore processing into uranium concentrate (sodium diuranate), subsequently conveyed to tailing ponds in slurry form. Solid wastes, on the other hand, predominantly consist of waste rock fragments produced during mining operations. A notable observation underscores the significance of self-absorption correction factors: In their absence, the measured values of alpha-specific activity experience substantial underestimation. This investigation yields self-absorption correction factors that have been quantified for varying source thicknesses. For liquid wastes, a second-degree polynomial fit, and for solid waste, a linear fit have been applied to these correction factors, facilitating improved accuracy in alpha activity measurements within radioactive samples. This research not only enhances our understanding of the intricate interplay between source thickness and self-absorption but also provides valuable insights for refining measurement methodologies in radiological assessments, especially concerning gross alpha activities in radioactive waste materials.

Traffic noise is emerging as major challenge for cities in India. It affects human health in terms of annoyance and other major health problems. This study aims to develop a traffic noise model for mid-sized cities. Vehicle noise and spot speed of individual vehicles were studied to develop a reference energy mean emission level (REMEL) by using the sound level meter from a reference distance of 7.5 m from the centerline of a nearby lane under free flow condition. This urban traffic noise model is specific to different geographical regions and depends on vehicle categories and characteristics of in use vehicles. Subsequently, mid-block studies were conducted for measuring traffic noise L_eq (in dB(A)), average speed, and traffic volumes of different vehicle categories. To develop the traffic noise prediction model, physical condition of the road, carriageway width, width of the footpath, median size, number of lanes, and ground cover (hard or soft) need to be accounted for. A modified traffic noise prediction model has been developed using REMEL models and different adjustment factors. Subsequently, the correlation analysis was performed between predicted and observed L_eq (in dB(A)) to check the model fitness by correlation coefficient R² = 0.76 and mean absolute percentage error is ranged from 0.8 to 1.2% for the predicted and observed L_eq at all the selected sites of measurement periods for the Kanpur city. With this calibrated model, a noise map has been developed to identify noise hotspots during different time intervals within the city.

In an era defined by energy security, healthcare advancements, and the pursuit of clean energy solutions, nuclear energy emerges as a potent candidate. However, a major bottleneck in its growth is the hindrance posed by the extrapolation of risk due to high-dose radiation to the low-dose region (< 100 mSv), according to the linear no-threshold (LNT) model. This creates undue radiophobia among the members of public leading to resistance against the applications of radiation for societal uses. This perspective article proposes a quantum approach to augment a hormesis or threshold model as an alternative to the LNT model while also discussing the LNT’s fallacies. To provide a more fundamental explanation to the several nonlinear biological processes underpinning such alternative models, this article suggests a quantum biology approach. Drawing inspiration from celebrated quantum biology examples across photosynthesis, magnetoreception and olfaction, this article discusses ways in which nontrivial quantum phenomena can explain nonlinear low doses processes such as upregulation of reactive oxygen species, DNA repair mechanisms, and other adaptive responses. By presenting quantum biology as a fundamental basis for nonlinearity, this article tries to underscore the potential of scientifically driven hormesis/threshold model to challenge the LNT model and maximize the numerous peaceful societal applications of nuclear energy.