Passive monitoring of nitrogen dioxide in urban air: A case study of Durban metropolis, South Africa

Moodley, Kandasamy G.; Singh, Shalini; Govender, Suendran

doi:10.1016/j.jenvman.2011.03.040

Cited by 20 publications

(25 citation statements)

References 28 publications

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“…This study was conducted for a duration of one month, with pollutant concentrations measured at weekly intervals, which aligns with previous studies [23] [38]. Heal et al [39] and Heal and Cape [40] also reported that weekly measurement of four times (1 week × 4) showed higher accuracy than continuous measurement for a month, as this duration leaves enough time for reagent to efficiently absorb NO 2 before the period of TEA photo-degradation [41].…”

Section: Storage and Exposure Durationsupporting

confidence: 82%

“…High wind speed tends to reduce NO 2 concentration by aiding pollutant transportation and dispersion and vice versa in the direction of up-wind [21] [22]. Precipitation reduces NO 2 concentration by enabling pollutant deposition, hence pollution is usually low during the wet (rainy) season [23] [24]. Also, Nitrogen dioxide reacts and water during the wet season to form acid rain (Nitric acid), thereby reducing atmospheric NO 2 concentrations [25] [26].…”

Section: Factors That Influence No2 Concentrationmentioning

confidence: 99%

“…Heal et al [39] and Heal and Cape [40] also reported that weekly measurement of four times (1 week × 4) showed higher accuracy than continuous measurement for a month, as this duration leaves enough time for reagent to efficiently absorb NO 2 before the period of TEA photo-degradation [41]. Moodley et al [23] likewise stipulated seven days as the optimal period it takes for the impregnated mesh to be saturation with NO 2 .…”

Section: Storage and Exposure Durationmentioning

confidence: 99%

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Passive Sampling of Ambient Nitrogen Dioxide at Toll Plazas in Malaysia

Ekeu-wei¹,

Azuma²,

Ogunmuyiwa³

2018

OJAP

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With the increasing trend of development and industrialization in Malaysia, air pollution has become an inevitable part of the process, resulting from increased vehicular activities and industrial processes. Toll operators are potentially exposed to high levels of air pollutants from working in proximity to traffic pollution sources, thereby increasing their risk of health defects associated with air pollution exposure. This study assessed the levels of Nitrogen dioxide (NO 2 ) toll operators are exposed to, considering the influences traffic density and meteorological factors. This is intended to serve as an indicator of the cumulative pollution emanating from the combustion process of vehicles at toll plazas. Using Passive diffusion samplers saturated with Triethanolamine (TEA), the weekly indoor and outdoor NO 2 concentrations at tollbooth were measured at Sungai Besi (SB), Kajang (KJ) and Putra-Makhota (PM) toll Plazas, to capture the varying traffic densities of 138,000, 65,000 and 24,100 vehicles/day respectively. The results showed that NO 2 concentrations increase with traffic densities, and indoor NO 2 concentrations correlated highly with outdoor NO 2 concentrations (R 2 : SB = 0.767, KJ = 0.689 and PM = 0.877). The indoor/outdoor NO 2 ratio varied from 0.7 to 1.2 for all toll booths, suggesting pollution control in-efficiency, caused by technical and behavioural factors. Also, meteorological factors had no significant effect on nitrogen dioxide concentrations, contrary to previous studies, which is likely due to the far distance between tool plazas and meteorological stations. Furthermore, the NO 2 concentrations reported in this study were higher in comparison to weekly standards adopted in Germany (0.032 ppm) and previous literature. Therefore, toll operators are potentially exposed to high levels of pollution, and we advise that toll operators to wear pollution protection gears to reduce the risk of exposure, and the ventilation systems and mitigation measure (air curtain) reviewed to assess its efficiency.

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Section: Storage and Exposure Durationsupporting

confidence: 82%

Section: Factors That Influence No2 Concentrationmentioning

confidence: 99%

Section: Storage and Exposure Durationmentioning

confidence: 99%

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Passive Sampling of Ambient Nitrogen Dioxide at Toll Plazas in Malaysia

Ekeu-wei¹,

Azuma²,

Ogunmuyiwa³

2018

OJAP

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“…Amostradores de fluxo passivo apresentam a vantagem de não necessitarem de nenhuma fonte de energia externa para quantificar o fluxo continuamente, tornando-se, assim, uma alternativa mais econômica e aplicável em relação a outros métodos de detecção considerados ativos (Carlson et al, 2013), além de apresentarem a característica de fácil instalação em campo por não necessitarem de fonte de alimentação e cabos, podendo ser aplicados em locais remotos ou sem energia. Adicionalmente, exigem menos habilidade e experiência dos operadores, por serem métodos mais simples e ainda exigem menos investimento inicial de capital na implementação de um sistema de medição de amônia (Dore et al, 2004).O custo da amostragem por difusão passiva foi estimado por Moodley et al (2011), como 50 vezes menor que o custo da amostragem ativa.…”

Section: Métodos De Difusão Passivaunclassified

Métodos De Difusão Passiva Para Quantificação De Amônia Em Instalações Abertas Para Produção Animal

Sousa

Tinôco

Saráz

et al. 2015

Revista Brasileira De Engenharia De Biossistemas

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RESUMOO objetivo deste estudo foi comparar os mencionados dois métodos de difusão passiva por poderem se adaptar mais facilmente às instalações que trabalham com ventilação natural durante a maior parte do tempo, com base em resultados de pesquisas já existentes com estudos relacionados a diversas características de ambos os métodos. O método Saraz é uma nova metodologia que vem sendo testada e aperfeiçoada para a operação em ventilação natural, e tem apresentado uma eficiência de recuperação de volatilização de amônia maior que 80 %. O método "Ferm Tube" constitui o primeiro amostrador de fluxo passivo, tendo sido principalmente aplicado para determinar as emissões de NH 3 em confinamentos de bovinos. Os dois métodos foram comparados em termos de requisitos, tais como: custo, eficiência, aplicabilidade e uso em instalações abertas. No geral, em condições de ventilação natural, o método Saraz mostrou-se mais apropriado que o método Ferm Tube. Porém a escolha entre um ou outro método vai depender de uma série de condições, como recursos econômicos, disponibilidade de reagentes e laboratórios, tipos de análises possíveis de serem realizadas, além da precisão desejada e grau de dificuldade de operação. Palavras-chave: método de fluxo passivo, instalações animais, emissão de amônia METHODS OF PASSIVE DIFFUSION FOR AMMONIA DETERMINATION IN OPEN FACILITIES FOR ANIMAL PRODUCTION ABSTRACTThe aim of this study was to compare the two methods mentioned by passive diffusion may adapt more easily to facilities that work with natural ventilation for most of the time, based on results from existing surveys related to various characteristics of both studies methods. The Saraz is a new methodology that has been tested and optimized for operation on natural ventilation, and has shown a recovery efficiency of volatilization of ammonia greater than 80%. The "Ferm Tube" is the first flow and passive sampler, have been mainly used for determining the emission of NH 3 in feedlot cattle. The two methods were compared in terms of requirements, such as cost, efficiency, applicability and usability in open facilities. Overall, in terms of natural ventilation Saraz the method was more appropriate than Ferm Tube. However, the choice between one or other method will depend on a number of conditions such as economic resources and availability of laboratory reagents, possible types of analysis to be performed, in addition to the desired precision and difficulty of operation.

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“…Nitrogen dioxide is a constituent mixture of nitrogen oxides [NO x = NO + NO 2 ] and it is mostly formed during combustion processes. Mobile and stationary combustion sources have been reported to be the major anthropogenic source of NO 2 in the atmosphere [6] [7]. NO 2 is alongside NO, a major regulator of the oxidizing ability of the troposphere through regulating the buildup and fate of radical species including hydroxyl radicals.…”

mentioning

confidence: 99%

Emission of Combustible Gases at Traffic and Practising Waste Dumpsite in Freetown, Sierra Leone: A Pilot Study

Williams¹,

Beah²,

Taylor³

et al. 2017

ACS

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An assessment of the emission of combustible gases in developing countries requires reliable analytical realtime monitors that can rapidly screen them with minimal handling. Considering the expensive nature of monitoring environmental pollutants, chemical sensors are expected to play a pivotal role in measuring and recording environmental data. The Drager X am 5000 was used to report emission levels of combustible gases in this study, namely; nitrogen dioxide (NO 2 ), sulphur dioxide (SO 2 ) and carbon monoxide (CO) at traffic and practising waste dumpsite in Freetown, the main city of Sierra Leone. Hourly average values for the three pollutants were recorded in the morning, afternoon and evening periods, respectively. The range of values were 18 -76 ppb for NO 2 , 211 -506 ppb for SO 2 and 11 -14 ppm for CO at traffic site; and 6 -16 ppb for NO 2 , 118 -276 ppb for SO 2 and 8 -15 ppm for CO at the dumpsite, respectively. There were significantly high hourly variations for NO 2 and SO 2 at the traffic site and for CO and SO 2 at the dumpsite. Evidence of peak values showed emission levels that were considered dangerous for human exposure. This pilot study revealed that combustible gases released in certain areas of the capital city are a concern for both public health officials and environmental advocates.

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Passive monitoring of nitrogen dioxide in urban air: A case study of Durban metropolis, South Africa

Cited by 20 publications

References 28 publications

Passive Sampling of Ambient Nitrogen Dioxide at Toll Plazas in Malaysia

Passive Sampling of Ambient Nitrogen Dioxide at Toll Plazas in Malaysia

Métodos De Difusão Passiva Para Quantificação De Amônia Em Instalações Abertas Para Produção Animal

Emission of Combustible Gases at Traffic and Practising Waste Dumpsite in Freetown, Sierra Leone: A Pilot Study

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