Atmospheric Monitoring System Research Articles

Conversion factors bridging radiocative fission product distributions in the primary containment vessel of Fukushima daiichi npp and dose rates measured by the containment atmosphere monitoring system

Multi-term fission product (FP) analysis procedures were developed to determine FP distribution all over the Fukushima Daiichi nuclear power plant (F1) not only for analyzing accident propagation but also for planning its decommissioning projects. They should be validated based on the measured FP data. One of the useful tools for their validation was application of the dose rate data monitored by the containment atmosphere monitoring system (CAMS). However, in order to compare the data with different characteristics and dimensional units, e.g., FP distribution (kg, Bq) and dose rate (Sv/h), application of the conversion factors bridging them would be effective and useful. In order to prepare speedy, easy-to-handle and tractable procedures to calculate radiation dose rates at the CAMS detector locations, dose rate conversion factors were determined for major source locations and major radionuclides. The dose rates could be easily calculated by multiplying FP amounts obtained with the multi-term FP analysis procedures by the conversion factors.This paper introduces the procedures to calculate the conversion factors based on a point kernel integral shielding calculation code, QAD-CGGP2. Then, the determined conversion factors for the 460 MWe BWR (1F Unit 1) and for the 780 MWe BWR (Units 2 and 3) are listed and the differences in those due to the reactor sizes are discussed.

An approach toward evaluation of long-term fission product distributions in the Fukushima Daiichi nuclear power plant after the severe accident

The safe completion of the Fukushima Daiichi Nuclear Power Plant decommissioning projects requires that the long-term distributions of fission products (FPs) as well as fuel debris for the entire plant be understood. The fuel debris is going to be removed from the plant under the severe conditions of FPs being scattered during major decommissioning work, and then, the decommissioning projects are going to be terminated by storing safely the removed debris as recovered fertile materials or as materials for final radioactive waste disposal.In order to determine the FP distribution in the plant for the long period from the accident occurrence to the termination of the plant decommissioning, procedures for analyzing short-, medium- and long-term FP behaviors has been proposed. The proposed procedures should be improved by applying the FP data measured in the plant and validated based on the fed-back data. Then, the accuracy-improved procedures should be applied to estimate FP distributions during each phase of the decommissioning projects.First the paper outlines the short-, medium- and long-term FP transfer analyses. Then, their applicability and some examples of their validations based on dose rate data of the containment atmosphere monitoring system (CAMS) of Unit 1 are introduced.(195 words)

Wireless network design for construction of atmospheric and marine environment monitoring system using buoy

It has used buoy for efficient domestic farm operations and fishermen fish. Buoy uses IoT-based communication to transmit water temperature, salinity, humidity, wind speed, etc. to fishers in real time. In this paper, we utilize LoRa, which enables communication in the marine environment, to construct a network and apply it to an actual buoy for monitoring. The implemented LoRa uses the 900MHz band to configure the network. The sensor consisted of a sensor that can monitor the atmospheric environment and a sensor that can monitor the marine environment. In addition, the information received in real time will be provided to the fishing village host. The fishermen were fully aware of this and took appropriate measures to conduct sea trials.

Multiparametric measuring system for atmospheric monitoring

There are several studies in the literature on monitoring carbon dioxide concentrations in combination with various other parameters to assess indoor air quality. However, no study describes the monitoring of air quality in different locations of the same environment. The characterization of the spatial distribution of atmospheric parameters can contribute to more appropriate analyses, providing customized planning’s for improvements. The present work develops a multiparametric measuring system for real-time monitoring of the spatial distribution of carbon dioxide, temperature, humidity, particulate matter, volatile organic compounds, and barometric pressure. Preliminary results indicate the necessity of multiple-location measurement for appropriate air quality analyses.

Influence of a weak typhoon on the vertical distribution of air pollution in Hong Kong: A perspective from a Doppler LiDAR network

High particulate matter (PM) and ozone (O3) concentration in Hong Kong are frequently observed during the summertime typhoon season. Despite the critical effect of a typhoon on air pollution, contributions of vertical wind profile and cloud movement during transboundary air pollution (TAP) on surface PM and O3 concentration have yet to be fully understood. This work is the first study to apply a network of Doppler light detection and ranging (LiDAR) as well as back trajectory analysis to comprehensively analyze the effect of a weak Typhoon (Danas) occurring during 16-19 July 2019 on different variations in PM and O3 concentration. During the typhoon Danas, three types of surface air pollution with five episodes were identified: (1) low PM and high O3 concentration; (2) co-occurring high PM and O3 concentration and (3) high PM and low O3 concentration. Employing our 3D Real-Time Atmospheric Monitoring System (3DREAMs) along with surface observations, we found the important role of TAP in the increases in surface PM and O3 concentration with significant vertical wind shear that transported air pollutants at upper levels, and strong vertical mixing that brought air pollutants to the ground level. Cloud movement related to typhoon periphery, as well as high solar radiation due to sinking motion and remote transport by continental wind, have an impact on local O3 concentration. For the substantial difference in O3 concentration between two air quality measurement sites, the similar vertical aerosol distributions and wind profiles suggest the comparable TAP contributions at the two sites and thus infer the critical role of local O3 photochemical process in the O3 difference. This work comprehensively reveals the influences of a weak typhoon on variations in PM and O3 during the five episodes, providing important references for air quality monitoring and forecast in regions under the influence of typhoon.

Global impact of landscape fire emissions on surface level PM2.5 concentrations, air quality exposure and population mortality

Airborne fine particulate matter (PM2.5) represents the greatest ambient air pollution risk to health. Wildfires and managed burns, together referred to hereafter as ‘landscape’ fires, are a significant PM2.5 source in many regions worldwide, able to affect air quality in areas far away from the fires themselves. We use 0.125°, 3 hourly outputs (2016–2019) from the Copernicus Atmospheric Monitoring System (CAMS) to investigate patterns of global population exposure to ambient surface level PM2.5, and specifically to the contribution coming from landscape fires. We calculate both the air quality impacts and annual average mortality at the level of the nation state, and our analysis highlights both the burden of poor air quality and the significance of landscape fire sources in developing nations in particular. We find 143 countries to have an average population weighted (PW) total PM2.5 surface level concentration exceeding the 10 μg m−3 guideline recommended by WHO, with 67.2 million people annually exposed to PM2.5 levels classed as ‘hazardous’ (>250.5 μg m−3) according to the US Environmental Protection Agency (EPA) air quality index (AQI). Landscape fires alone result in 44 million people annually being exposed to air quality considered unhealthy (PM2.5 > 55 μg m−3), and 4 million to that considered ‘hazardous’ to health (>250.5 μg m−3). Populations in central and west Africa and south and south east Asia are most affected by the landscape fire smoke, and eight countries exceed the WHO annual mean 10 μg m−3 guideline from this source only - with the contribution from fires highest in Laos (61% of the total PM2.5), Democratic Republic of Congo (45%) and Sierra Leone (44%). Combining published dose-response functions with these landscape-fire PM2.5 contributions, we estimate that 677,745 premature deaths annually result from exposure to landscape fire smoke, with almost 39% of these in children under five. This mortality represents between 8 and 21% of the estimated 3.2 to 8.9 million people dying annually from outdoor air pollution exposure, highlighting landscape fires as a significant contributor. Our results indicate that environmental programmes aimed at lessening the use of fire in land clearance and agricultural residue management in developing nations would very likely result in significant co-benefits for health.

Optimization and Simulation of Atmospheric Environment Monitoring System Based on Wireless Sensor

With the acceleration of urbanization, the problems in urban construction are becoming increasingly prominent, especially in air pollution. In order to deal with a series of problems brought by urbanization, the state has formulated the strategic layout of smart city construction. As an important measure and practice for the development of smart city, atmospheric environment monitoring is the premise of controlling atmospheric environment problems and plays a great role in environmental protection. The traditional automatic atmospheric environment monitoring station has complex structure, expensive price, and harsh working conditions, which is difficult to be popularized throughout the country. Aiming at the problems of poor expansibility and low intelligence of atmospheric environment monitoring system, an atmospheric environment monitoring system based on wireless sensor network is proposed. The system designs sensor module, networking module, gateway module, and monitoring interface, studies the accuracy of data collected by the system and the coverage of wireless sensor network, filters the environmental data collected by the sensor module, optimizes the layout of networking module by using improved virtual force algorithm, and finally tests the system. The experimental results show that the system realizes the remote monitoring of temperature, humidity, air pressure, and PM2.5 data, and the monitoring data is real and reliable. The improved virtual force algorithm improves the coverage of wireless sensor networks. Comparing the data collected by the system with the monitoring data of the cause control station, the average relative errors of PM2.5 and other particle parameters and NOx and other gas parameters monitored by the system are 3.81% and 3.48%, respectively; the system can be widely used in various environmental monitoring fields.

Status and inspiration on the development of the air monitoring system ANITA for European Space Agency

This paper describes the technical characteristics and application status of ANITAII (Analysing Interferometer for Ambient Air), an atmospheric monitoring system currently used by ESA (European Space Agency), reveals the characteristics and advantages of FTIR (Fourier transform infrared spectroscopy) technology in multi-component gas monitoring, and analyzes the application prospect of FTIR technology in the field of environmental monitoring.

Prototipo para el análisis del crecimiento vehicular y de estaciones de monitoreo atmosférico

There is a universal recognition of the importance and need to establish more ambitious and effective climate actions in all the sectors involved; government, private sector and society with the aim of acting together to decrease and stop the increase in global temperature in the present century and thereby avoid devastating and irremediable effects on climate change. In this sense, the implementation of atmospheric monitoring systems has made it possible to identify the emissions of particulate and polluting gases directly related to gasoline and diesel engine vehicles; therefore, the objective of this project is to design a prototype system for mobile devices with the Android operating system, which allows projecting the increase or decrease of polluting gases using statistical data on vehicle growth and atmospheric monitoring stations in the State of Jalisco, Mexico, therefore it constitutes a valuable technological tool whose main contribution focuses on keeping the population informed about the importance of the reduction of contaminants that can deteriorate health.

THE ANALYSIS OF THE ATMOSPHERIC AIR MONITORING SYSTEM ACTIVE IN THE CITY OF PAVLODAR

The article is dedicated to the analysis of the atmospheric air monitoring system active in the city of Pavlodar. The problem of the atmospheric air pollution from motor transport, one of the sources of contamination, was considered. The data of the information bulletins of republican state enterprise "Kazgidromet" within the city of Pavlodar was studied and analyzed, which allowed to reveal the series of patterns: it was found that carbon monoxide, sulfur dioxide, nitrogen dioxide, nitrogen monoxide and particulate matter PM-10, PM-2.5 have been to a greater extent the atmospheric air contaminants. The analysis of the influence of motor transport on the environment was conducted, the size composition of exhaust gases of engines of various types of motor transport was described in details by the authors. Moreover, the street traffic congestion was determined, proposals and required recommendations on optimization of the given situation were made.

Self-powered/self-cleaned atmosphere monitoring system from combining hydrovoltaic, gas sensing and photocatalytic effects of TiO2 nanoparticles

A new self-powered/self-cleaned atmosphere monitoring system has been fabricated from TiO2 nanoparticles through combining hydrovoltaic, gas sensing and photocatalytic effects. The TiO2 nanoparticle film can convert natural thermal energy into electricity (hydrovoltaic effect) by the spontaneous water evaporation. The hydrovoltaic/gas-sensing coupling effect of TiO2 nanoparticle offers the water-evaporation-powered gas detection performance, and the outputting voltage/current has a good response to the surrounding gas atmosphere, directly acting as the gas sensing signal. The zeta potential of TiO2 is changed by the surface adsorption of gas molecules, and thus affects the electricity output of the system. The outputting electricity can directly power a wireless transmitter for transmitting the sensing information to external platform, and the whole system can work independently without electricity power supply. The rainwater can be used as the fuel of the system, and thus the system can be used outdoors without scheduled maintenance. Moreover, the photocatalytic activity of TiO2 can effectively degrade the organic pollutants on the film under photo illumination, leading to a self-clean behavior of the system. The system can probably promote the development of green sensing techniques with evaporation-induced ability.

About creation of a hybrid multi-level atmospheric air monitoring system in the Republic of Tatarstan

The existing system of instrumental monitoring of the state of atmospheric air in the Republic of Tatarstan systematically reveals the facts of unsatisfactory quality of atmospheric air, in this connection, special attention has been paid to the work on regulating the impact of emissions on atmospheric air by means of calculated monitoring. The article notes that by now all the necessary legal framework has been created for creating a hybrid multi-level atmospheric air monitoring system in the Republic of Tatarstan. The paper provides a justification for the need to implement a hybrid multi-level atmospheric air monitoring system for three levels: the level "Enterprise" or "group of enterprises", the level" Municipality", the level"Subject of the Russian Federation the Republic of Tatarstan". The General scheme of the organization of environmental data collection in the Republic of Tatarstan and the scheme of the integrated architecture of the environmental data collection system are presented. The results of the implementation of a hybrid multi-level atmospheric air monitoring system in the environmental policy of the Republic of Tatarstan are presented

Field Verification of an Improved Mine Fire Location Model

Underground mine fires remain a concern for mine operators, posing a health and safety risk to mineworkers. In the last decade, the number of mine fires has decreased significantly; however, dealing with an unknown fire in underground mines can be a challenging task, which could lead to a hazardous condition for miners during an evacuation and rescue operation. A timely detection of a mine fire and monitoring its characteristics, namely size and location, are of great importance in reducing the risk of mine fire injuries. A new improved fire location algorithm has been developed and integrated into an Atmospheric Monitoring System (AMS) program by researchers from the National Institute for Occupational Safety and Health (NIOSH). This paper describes the new fire location model and presents the results of verification fire tests conducted at the Safety Research Coal Mine (SRCM) facility of the Pittsburgh Mining Research Division (PMRD) using the collected AMS data. NIOSH is endeavoring to develop workplace solutions to improve detection of and reduce the risk of hazardous conditions in mines. The results demonstrate successful application of the improved fire location model and provide a useful tool for solving the problem of unknown fire location and reducing the risk of hazardous conditions.

Component composition of atmospheric dusts as a characteristic of environmental pollution

Air pollution from urban areas by solid dust particles potentially affects the level of chemicals in the soils of the surrounding area. Under the influence of gravity, solid particles settle, fall out in the form of rain and snow. The chemical composition of solid particles of atmospheric air contains a multicomponent mixture containing both organic and inorganic impurities, including extremely and highly dangerous ones. Based on the example of three central regions of Perm, comprehensive studies of the solid component of atmospheric air are carried out. The studies included determining the concentration levels of suspended solids and fine fractions PM10 and PM2.5, studying the component composition, forming a profile of solid particles and studying the morphological properties of the identified particles. During the study, an averaged profile of dust particles was formed, which is characterized by a wide range of chemicals, including: oxides of iron, calcium, silicon, aluminum, etc. The multicomponent nature of dust pollution of atmospheric air is confirmed by morphological features, solid particles are represented by a wide range of forms and various structures. Based on the results of the studies, proposals are made for the organization of environmental monitoring based on a detailed study of the component composition and inclusion of fine fractions PM10 and PM2.5 in the atmospheric air monitoring system of Roshydromet.

An Improved Method to Calculate the Heat Release Rate of a Mine Fire in Underground Mines

Continuous monitoring of carbon monoxide and other fire-related parameters by means of an atmospheric monitoring system (AMS) has been used by the mining industry for early fire detection in underground mines. The National Institute for Occupational Safety and Health (NIOSH) initiated a project to integrate real-time AMS sensor data with NIOSH’s mine fire simulation program, MFIRE 3.0, to simulate and predict the spread of smoke that would provide assistance to mine fire emergency response personnel. Determining the heat release rate of a fire using the monitored sensor data was a critical component of the successful completion of this project. NIOSH researchers developed a direct method to calculate the heat release rate when a fire is within close range of sensors. However, this method is only applicable to the case where a fire occurs in AMS-monitored airways. This paper presents an improved method for determining the fire heat release rate for complicated scenarios where a fire is distant from sensors and airflow splits and merges are present. The method was validated using a full-scale diesel fuel fire test conducted in the Safety Research Coal Mine at the Pittsburgh Mining Research Division and can help mine operators and safety personnel make informed decisions during a fire emergency.

Mini-Scheimpflug lidar system for all-day atmospheric remote sensing in the boundary layer.

Development of a lightweight, low-cost, easy-to-use and low-maintenance lidar technique has been of great interest for atmospheric aerosol remote sensing in recent years and remains a great challenge. In this work, an 808 nm mini-Scheimpflug lidar (SLidar) system with about 450 mm separation between the transmitter and the receiver has been developed by employing a 114 mm aperture Newtonian telescope (F4). System performances, such as the beam characteristic, the range resolution, and the signal-to-noise ratio of the lidar signal, have been carefully investigated. Despite employing a small receiving aperture, all-day measurements were still feasible with about a one-minute signal averaging for both the horizontal urban area monitoring and the slant atmospheric sounding in the boundary layer. The lidar signal in the region of 29-50 m with a scattering angle less than 179.5° could be slightly underestimated due to the variation of the phase function. The extinction coefficient evaluated in the region between 29 and 2000 m according to the Klett method agreed well with the concentrations of particulate matters for both horizontal and slant measurements. The promising result demonstrated in this work has shown great potential to employ the robust mini-SLidar system for atmospheric monitoring in the boundary layer.

Application of a taxi-based mobile atmospheric monitoring system in Cangzhou, China

Increasing air pollution as a result of rapid urbanization is of growing concern worldwide, particularly in populous developing countries. Sparse routine monitoring stations are not sufficient to capture the heterogeneity of air pollution levels in complex urban regions. In this study, a taxi-based mobile atmospheric monitoring system was applied to map the air pollution levels in Cangzhou, China. Fifty taxis equipped with particulate matter (PM) sensors were used to characterize the spatial and temporal variability of PM pollutants. Statistical analyses indicate that the mobile system can provide comparable data to that of fixed monitoring stations and help map the urban air quality. Moreover, the high-resolution air pollution map provided by the mobile monitoring system could address current data gaps, thereby providing valuable information to protect the public health and guide policy design.

Observation of Turbulent Mixing Characteristics in the Typical Daytime Cloud-Topped Boundary Layer over Hong Kong in 2019

Turbulent mixing is critical in affecting urban climate and air pollution. Nevertheless, our understanding of it, especially in a cloud-topped boundary layer (CTBL), remains limited. High-temporal resolution observations provide sufficient information of vertical velocity profiles, which is essential for turbulence studies in the atmospheric boundary layer (ABL). We conducted Doppler Light Detection and Ranging (LiDAR) measurements in 2019 using the 3-Dimensional Real-time Atmospheric Monitoring System (3DREAMS) to reveal the characteristics of typical daytime turbulent mixing processes in CTBL over Hong Kong. We assessed the contribution of cloud radiative cooling on turbulent mixing and determined the altitudinal dependence of the contribution of surface heating and vertical wind shear to turbulent mixing. Our results show that more downdrafts and updrafts in spring and autumn were observed and positively associated with seasonal cloud fraction. These results reveal that cloud radiative cooling was the main source of downdraft, which was also confirmed by our detailed case study of vertical velocity. Compared to winter and autumn, cloud base heights were lower in spring and summer. Cloud radiative cooling contributed ~32% to turbulent mixing even near the surface, although the contribution was relatively weaker compared to surface heating and vertical wind shear. Surface heating and vertical wind shear together contributed to ~45% of turbulent mixing near the surface, but wind shear can affect up to ~1100 m while surface heating can only reach ~450 m. Despite the fact that more research is still needed to further understand the processes, our findings provide useful references for local weather forecast and air quality studies.

Main Findings, Remaining Uncertainties and Lessons Learned from the OECD/NEA BSAF Project

The Organisation for Economic Co-operation and Development (OECD)/Nuclear Energy Agency (NEA) Benchmark Study of the Accident at the Fukushima Daiichi Nuclear Power Station (BSAF), which started in 2012 and continued until 2018, was one of the earliest responses to the accident at Fukushima Daiichi. The project, divided into two phases, addressed the investigation of the accident at Units 1, 2, and 3 by severe accident (SA) codes until 500 h, focusing on thermal hydraulics, core relocation, molten corium concrete interaction (MCCI), and fission product release and transport. The objectives of the BSAF were to make up plausible scenarios based primarily on SA forensic analysis, support the decommissioning, and inform SA code modeling. The analysis and comparison among the institutes have brought up vital insights regarding the accident progression, identifying periods of core meltdown and relocation and reactor pressure vessel (RPV) and primary containment vessel (PCV) leakage/failure through the comparison of pressure, water level, and containment atmosphere monitoring system (CAMS) signatures. The combination of code results and inspections (muon radiography, PCV inspection) has provided a picture of the current status of the debris distribution and plant status. All units present a large relocation of core materials and all of them present ex-vessel debris with Unit 1 and Unit 3 showing evidence of undergoing MCCI. Uncertainties have been identified, in particular on the time and magnitude of events such as corium relocation in the RPV and into the cavity floor and RPV and PCV rupture events. Main uncertainties resulting from the project are the large and continuous MCCI progression predicted by basically all the SA codes and the leak pathways from the RPV to the PCV and the PCV to the reactor building and environment. The BSAF project represents a pioneering exercise that has set the basis and provided lessons learned not only for code improvement but also for the development of new related projects to investigate in detail further aspects of the Fukushima Daiichi accident.

Study on integration of real-time atmospheric monitoring system data and MFIRE simulation

ABSTRACT The past several decades have seen a steady increase in the use of atmospheric monitoring systems (AMS) in underground mines as sensor technology has advanced and costs for this technology have decreased. The AMS is a reliable tool for early mine fire warning by detecting gaseous products of combustion in underground mines. During a mine fire emergency, mine decision makers rely heavily on prompt and accurate knowledge of the ventilation and fire situation in the mine, such as fire location, fire size, and the spread of smoke to make effective and efficient decisions on firefighting strategies and miner evacuation. Meanwhile, a prediction of the potential for fire development at a later time, such as whether the currently designated mine escapeways will be contaminated by smoke and toxic gases with the progress of the fire, is critical for effective decision making to save lives that are in danger. The AMS monitoring data, including carbon monoxide concentration, airflow rate, smoke spread, etc., can provide information as to whether the smoke has reached the locations where AMS sensors are installed and if a mine-wide smoke spread has occurred. The National Institute for Occupational Safety and Health has undertaken a task to integrate real-time AMS monitoring data with the mine fire simulation program, MFIRE, to simulate and predict the spread of smoke and toxic gas in a ventilation network based on the real-time AMS data. This article reports the developed real-time method for characterizing the size and location of an underground mine fire and for predicting the spread of contaminants throughout the mine ventilation network using sensor data from the AMS.