Abstract:
UNLABELLED:Numerous techniques have been developed over the years for reducing aerosol exposure in indoor air environments. Among indoor air purifiers of different types, ionic emitters have gained increasing attention and are presently used for removing dust particles, aeroallergens and airborne microorganisms from indoor air. In this study, five ionic air purifiers (two wearable and three stationary) that produce unipolar air ions were evaluated with respect to their ability to reduce aerosol exposure in confined indoor spaces. The concentration decay of respirable particles of different properties was monitored in real time inside the breathing zone of a human manikin, which was placed in a relatively small (2.6 m3) walk-in chamber during the operation of an ionic air purifier in calm air and under mixing air condition. The particle removal efficiency as a function of particle size was determined using the data collected with a size-selective optical particle counter. The removal efficiency of the more powerful of the two wearable ionic purifiers reached about 50% after 15 min and almost 100% after 1.5 h of continuous operation in the chamber under calm air conditions. In the absence of external ventilation, air mixing, especially vigorous one (900 CFM), enhanced the air cleaning effect. Similar results were obtained when the manikin was placed inside a partial enclosure that simulated an aircraft seating configuration. All three stationary ionic air purifiers tested in this study were found capable of reducing the aerosol concentration in a confined indoor space. The most powerful stationary unit demonstrated an extremely high particle removal efficiency that increased sharply to almost 90% within 5-6 min, reaching about 100% within 10-12 min for all particle sizes (0.3-3 microm) tested in the chamber. For the units of the same emission rate, the data suggest that the ion polarity per se (negative vs. positive) does not affect the performance but the ion emission rate does. The effects of particle size (within the tested range) and properties (NaCl, PSL, Pseudomonas fluorescens bacteria) as well as the effects of the manikin's body temperature and its breathing on the ionic purifier performance were either small or insignificant. The data suggest that the unipolar ionic air purifiers are particularly efficient in reducing aerosol exposure in the breathing zone when used inside confined spaces with a relatively high surface-to-volume ratio. PRACTICAL IMPLICATIONS:Ionic air purifiers have become increasingly popular for removing dust particles, aeroallergens and airborne microorganisms from indoor air in various settings. While the indoor air cleaning effect, resulting from unipolar and bipolar ion emission, has been tested by several investigators, there are still controversial claims (favorable and unfavorable) about the performance of commercially available ionic air purifiers. Among the five tested ionic air purifiers (two wearable and three stationary) producing unipolar air ions, the units with a higher ion emission rate provided higher particle removal efficiency. The ion polarity (negative vs. positive), the particle size (0.3-3 microm) and properties (NaCl, PSL, Pseudomonas fluorescens bacteria), as well as the body temperature and breathing did not considerable affected the ionization-driven particle removal. The data suggest that the unipolar ionic air purifiers are particularly efficient in reducing aerosol exposure in the breathing zone when they are used inside confined spaces with a relatively high surface-to-volume ratio (such as automobile cabins, aircraft seating areas, bathrooms, cellular offices, small residential rooms, and animal confinements). Based on our experiments, we proposed that purifiers with a very high ion emission rate be operated in an intermittent mode if used indoors for extended time periods. As the particles migrate to and deposit on indoor surfaces during the operation of ionic air purifiers, some excessive surface contamination may occur, which introduces the need of periodic cleaning these surfaces.
journal_name
Indoor Airjournal_title
Indoor airauthors
Grinshpun SA,Mainelis G,Trunov M,Adhikari A,Reponen T,Willeke Kdoi
10.1111/j.1600-0668.2005.00364.xsubject
Has Abstractpub_date
2005-08-01 00:00:00pages
235-45issue
4eissn
0905-6947issn
1600-0668pii
INA364journal_volume
15pub_type
杂志文章相关文献
INDOOR AIR文献大全abstract::It is inappropriate to use the assumption of instantaneously well-mixed zones to model airflows and pollutant transport in large indoor spaces. We investigate two approaches for describing the details of airflows in large indoor spaces, for accuracy and suitability for integration with multi-zone infiltration models. ...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1034/j.1600-0668.2003.00160.x
更新日期:2003-06-01 00:00:00
abstract::Ventilation is pivotal in terms of securing optimum indoor air quality. In addition, it also has a major impact on energy use in buildings. It is important, therefore, that the role and impact of ventilation is fully understood and that ventilation is employed efficiently. The purpose of this paper is to review these ...
journal_title:Indoor air
pub_type: 杂志文章,评审
doi:10.1034/j.1600-0668.2000.010003193.x
更新日期:2000-09-01 00:00:00
abstract::Many ice rink arenas have ice resurfacing equipment that uses fossil fuel as power. The combustion byproducts are a major source of contamination. Ventilation along with other pollution source control measures is the most widely applied strategy to lower the contaminant level below the threshold limit and maintain acc...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1034/j.1600-0668.2001.110206.x
更新日期:2001-06-01 00:00:00
abstract::Available studies indicate that indoor air pollution (IAP) from household cooking and space heating apparently causes substantial ill-health in developing countries where the majority of households rely on solid fuels (coal or biomass as wood, crop residues, and dung), but there are many remaining uncertainties. To pi...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1034/j.1600-0668.2002.01137.x
更新日期:2002-09-01 00:00:00
abstract::This study involved the development of a model for evaluating the potential costs and benefits of ozone control by activated carbon filtration in single-family homes. The modeling effort included the prediction of indoor ozone with and without activated carbon filtration in the HVAC system. As one application, the mod...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12220
更新日期:2016-06-01 00:00:00
abstract:UNLABELLED:A cross-sectional study was carried out at Tianjin University campus, China, from February 21 to June10, 2006, to survey the association between dampness in dorms and allergy and airways infection among college students. The health and dampness condition were self-reported by 3436 students living in 1511 dor...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/j.1600-0668.2008.00577.x
更新日期:2009-04-01 00:00:00
abstract::Although many U.S. children spend time in child care, little information exists on exposures to airborne particulate matter (PM) in this environment, even though PM may be associated with asthma and other respiratory illness, which is a key concern for young children. To address this data gap, we measured ultrafine pa...
journal_title:Indoor air
pub_type: 杂志文章,多中心研究
doi:10.1111/ina.12408
更新日期:2018-01-01 00:00:00
abstract::Tuberculosis (TB) remains the airborne infection of global importance, although many environmental interventions to control TB apply to influenza and other infections with airborne potential. This review focuses on the global problem and the current state of available environmental interventions. TB transmission is fa...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12232
更新日期:2016-02-01 00:00:00
abstract::Airtight construction and high-performance thermal insulation materials are commonly considered important building features to enhance indoor thermal comfort while reducing thermal load. However, when water vapor is generated in such airtight indoor spaces, it cannot be discharged to the outside, causing interstitial ...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12622
更新日期:2020-03-01 00:00:00
abstract:UNLABELLED:In studying productivity, effects of environmental factors have focused only on performance. However, previous studies of the impact of the environment upon performance of mental tasks generally conclude that productivity research is somewhat confusing because the results are sometimes conflicting. In experi...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/j.1600-0668.2004.00281.x
更新日期:2004-01-01 00:00:00
abstract::At city level, personal monitoring is the best way to assess people's exposure. However, it is usually estimated from a few monitoring stations. Our aim was to determine the exposure to black carbon (BC) and BC dose for 45 schoolchildren with portable microaethalometers and to evaluate the relationship between persona...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12214
更新日期:2016-06-01 00:00:00
abstract:UNLABELLED:Indoor air quality (IAQ) has been a matter of public concern these days whereas air pollution is normally monitored outdoors as part of obligations under the National air quality strategies. Much little is known about levels of air pollution indoors. Simultaneous measurements of indoor and outdoor carbon mon...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/j.1600-0668.2004.00311.x
更新日期:2005-04-01 00:00:00
abstract::Outdoor traffic-related airborne particles can infiltrate a building and adversely affect the indoor air quality. Limited information is available on the effectiveness of high efficiency particulate air (HEPA) filtration of traffic-related particles. Here, we investigated the effectiveness of portable HEPA air cleaner...
journal_title:Indoor air
pub_type: 杂志文章,随机对照试验
doi:10.1111/ina.12502
更新日期:2018-11-01 00:00:00
abstract:UNLABELLED:The effects of the human convective boundary layer (CBL), room airflow patterns, and their velocities on personal exposure are examined. Two pollutants are studied which simulate particles released from the feet and generated at distances of 2 and 3 m by a human cough. A thermal manikin whose body shape, siz...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12177
更新日期:2015-12-01 00:00:00
abstract::Dispersion characteristics of expiratory aerosols were investigated in an enclosure with two different idealized airflow patterns: the ceiling-return and the unidirectional downward. A multiphase numerical model, which was able to capture the polydispersity and evaporation features of the aerosols, was adopted. Experi...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/j.1600-0668.2006.00426.x
更新日期:2006-08-01 00:00:00
abstract::This study reports the outcomes of a systematic literature review, which aims to determine the influence of four indoor environmental parameters - indoor air, thermal, acoustic, and lighting conditions -on the quality of teaching and learning and on students' academic achievement in schools for higher education, defin...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12745
更新日期:2020-09-24 00:00:00
abstract::In the context of airborne infection control, it is critical that the ventilation system is able to extract the contaminated exhaled air within the shortest possible time. To minimize the spread of contaminated air exhaled by occupants efficiently, a novel personalized ventilation (PV)-personalized exhaust (PE) system...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12127
更新日期:2015-04-01 00:00:00
abstract::The microbial content of air has as yet been little described, despite its public health implications, and there remains a lack of environmental microbial data on airborne microflora in enclosed spaces. In this context, the aim of this study was to characterize the diversity and dynamics of airborne microorganisms in ...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12053
更新日期:2014-02-01 00:00:00
abstract::The correspondence between impact factor profiles of self-reported skin sensation and of objectively determined skin symptoms was examined using data from the ProKlimA project (1994-1999). A sub-sample of 925 office workers participated in measurements of skin hydration and sebum content and responded to a questionnai...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1046/j.1600-0668.2003.00222.x
更新日期:2004-04-01 00:00:00
abstract::Occupants of aircraft have reported an array of symptoms related to general discomfort and irritation. Volatile organic compounds (VOCs) have been suggested to contribute to the reported symptoms. VOCs are from products used, bioeffluents from people and oxidation reaction products. Thirty-six healthy, young female su...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12392
更新日期:2017-11-01 00:00:00
abstract::As a basis for determining the lower limit of acceptable humidity in an indoor environment, experiments were conducted for 25 subjects to assess the maximum expected sensations of dryness, discomfort based on humidity, and intolerance based on humidity, under conditions of 26°C and 10% RH. As results, distinct negativ...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12717
更新日期:2021-01-01 00:00:00
abstract:UNLABELLED:Acute lower respiratory illnesses (ALRI) are the leading cause of death among children <5 years. Studies have found that biomass cooking fuels are an important risk factor for ALRI. However, few studies have evaluated the influence of natural household ventilation indicators on ALRI. The purpose of this stud...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/j.1600-0668.2011.00754.x
更新日期:2012-04-01 00:00:00
abstract::We investigated the physicochemical properties (size, shape, elemental composition, and endotoxin) of size resolved particulate matter (PM) collected from the indoor and corridor environments of classrooms. A comparative hazard profiling of these PM was conducted using human microvascular endothelial cells (HMVEC). Ox...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12341
更新日期:2017-05-01 00:00:00
abstract::A significant number of consumer goods and building materials can act as emission sources of flame retardants (FRs) in the indoor environment. We investigate the relationship between the emission source strength and the levels of 19 brominated flame retardants (BFRs) and seven organophosphate flame retardants (OPFRs) ...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12332
更新日期:2017-05-01 00:00:00
abstract::A mechanistic model that considers particle dynamics and their effects on surface emissions and sorptions was developed to predict the fate and transport of phthalates in indoor environments. A controlled case study was conducted in a test house to evaluate the model. The model-predicted evolving concentrations of ben...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12514
更新日期:2019-01-01 00:00:00
abstract::The most important indoor air pollutants have already been addressed with individual national guidelines or recommendations. However, an international set of guidelines or recommendations for indoor air quality (IAQ) is needed for these pollutants based on general and uniform rules for setting such standards. A major ...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1034/j.1600-0668.13.s.6.2.x
更新日期:2003-01-01 00:00:00
abstract:UNLABELLED:Nitrogen dioxide (NO2) is produced from the exhausts of vehicles and gas appliances and is known to pose certain health risks. In this study, we characterize the exposure to this substance during the first year of life, which is an important period of development. To this end, we used passive samplers to mea...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/j.1600-0668.2010.00646.x
更新日期:2010-06-01 00:00:00
abstract::Associations between size-fractionated indoor particulate matter (PM) and black carbon (BC) and heart rate variability (HRV) and heart rate (HR) in elderly women remain unclear. Twenty-nine healthy elderly women were measured for 24-hour HRV/HR indices. Real-time size-fractionated indoor PM and BC were monitored on th...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/ina.12449
更新日期:2018-05-01 00:00:00
abstract:UNLABELLED:This paper reports the abundance in indoor air and dust of eleven organophosphate esters and six phthalate esters. Both groups of these semi-volatile compounds are widely incorporated as additives into plastic materials used in the indoor environment, thus contributing to indoor exposure to industrial chemic...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/j.1600-0668.2010.00684.x
更新日期:2011-02-01 00:00:00
abstract:UNLABELLED:In this study, single-particle characterization of aerosol particles collected at an underground shopping area was performed for the first time. A quantitative single-particle analytical technique, low-Z particle electron probe X-ray microanalysis, was used to characterize a total of 7900 individual particle...
journal_title:Indoor air
pub_type: 杂志文章
doi:10.1111/j.1600-0668.2010.00677.x
更新日期:2011-02-01 00:00:00