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1.
D. Muyanja J. G. Allen J. Vallarino L. Valeri B. Kakuhikire D. R. Bangsberg D. C. Christiani A. C. Tsai P. S. Lai 《Indoor air》2017,27(5):1022-1029
The literature on the contribution of kerosene lighting to indoor air particulate concentrations is sparse. In rural Uganda, kitchens are almost universally located outside the main home, and kerosene is often used for lighting. In this study, we obtained longitudinal measures of particulate matter 2.5 microns or smaller in size (PM2.5) from living rooms and kitchens of 88 households in rural Uganda. Linear mixed‐effects models with a random intercept for household were used to test the hypotheses that primary reported lighting source and kitchen location (indoor vs outdoor) are associated with PM2.5 levels. During initial testing, households reported using the following sources of lighting: open‐wick kerosene (19.3%), hurricane kerosene (45.5%), battery‐powered (33.0%), and solar (1.1%) lamps. During follow‐up testing, these proportions changed to 29.5%, 35.2%, 18.2%, and 9.1%, respectively. Average ambient, living room, and kitchen PM2.5 levels were 20.2, 35.2, and 270.0 μg/m3. Living rooms using open‐wick kerosene lamps had the highest PM2.5 levels (55.3 μg/m3) compared to those using solar lighting (19.4 μg/m3; open wick vs solar, P=.01); 27.6% of homes using open‐wick kerosene lamps met World Health Organization indoor air quality standards compared to 75.0% in homes using solar lighting. 相似文献
2.
Ruolan Hu Shuxiao Wang Kristin Aunan Minjiang Zhao Lu Chen Zhaohui Liu Mette H. Hansen 《Indoor air》2019,29(3):403-412
High levels of PM2.5 exposure and associated health risks are of great concern in rural China. For this study, we used portable PM2.5 monitors for monitoring concentrations online, recorded personal time‐activity patterns, and analyzed the contribution from different microenvironments in rural areas of the Yangtze River Delta, China. The daily exposure levels of rural participants were 66 μg/m3 (SD 40) in winter and 65 μg/m3 (SD 16) in summer. Indoor exposure levels were usually higher than outdoor levels. The exposure levels during cooking in rural kitchens were 140 μg/m3 (SD 116) in winter and 121 μg/m3 (SD 70) in summer, the highest in all microenvironments. Winter and summer values were 252 μg/m3 (SD 103) and 204 μg/m3 (SD 105), respectively, for rural people using biomass for fuel, much higher than those for rural people using LPG and electricity. By combining PM2.5concentrations and time spent in different microenvironments, we found that 92% (winter) and 85% (summer) of personal exposure to PM2.5in rural areas was attributable to indoor microenvironments, of which kitchens accounted for 24% and 27%, respectively. Consequently, more effective policies and measures are needed to replace biomass fuel with LPG or electricity, which would benefit the health of the rural population in China. 相似文献
3.
Fine and ultrafine particle exposures on 73 trips by car to 65 non‐smoking restaurants in the San Francisco Bay Area
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A number of studies indicate cooking is a major source of exposure to particulate matter, but few studies have measured indoor air pollution in restaurants, where cooking predominates. We made 73 visits by car to 65 different non‐smoking restaurants in 10 Northern California towns while carrying portable continuous monitors that unobtrusively measured ultrafine (down to 10 nm) and fine (PM2.5) particles to characterize indoor restaurant exposures, comparing them with exposures in the car. The mean ultrafine number concentrations in the restaurants on dinner visits averaging 1.4 h was 71 600 particles/cm3, or 4.3 times the mean concentration on car trips, and 12.3 times the mean background concentration in the residence. Restaurants that cooked dinner in the same room as the patrons had higher ultrafine concentrations than restaurants with separate kitchens. Restaurant PM2.5 mass concentrations averaged 36.3 μg/m3, ranging from 1.5 to 454 μg/m3, but were relatively low on most visits: 43% of the indoor means were below 10 μg/m3 and 66% were below 20 μg/m3, with 5.5% above 100 μg/m3. Exposure to fine and ultrafine particles when visiting a restaurant exceeded the exposure a person received while traveling by car to and from the restaurant. 相似文献
4.
Matias Tagle Ajay Pillarisetti Maria Teresa Hernandez Karin Troncoso Agnes Soares Ricardo Torres Aida Galeano Pedro Oyola John Balmes Kirk R. Smith 《Indoor air》2019,29(2):252-262
In Paraguay, 49% of the population depends on biomass (wood and charcoal) for cooking. Residential biomass burning is a major source of fine particulate matter (PM2.5) and carbon monoxide (CO) in and around the household environment. In July 2016, cross‐sectional household air pollution sampling was conducted in 80 households in rural Paraguay. Time‐integrated samples (24 hours) of PM2.5 and continuous CO concentrations were measured in kitchens that used wood, charcoal, liquefied petroleum gas (LPG), or electricity to cook. Qualitative and quantitative household‐level variables were captured using questionnaires. The average PM2.5 concentration (μg/m3) was higher in kitchens that burned wood (741.7 ± 546.4) and charcoal (107.0 ± 68.6) than in kitchens where LPG (52.3 ± 18.9) or electricity (52.0 ± 14.8) was used. Likewise, the average CO concentration (ppm) was higher in kitchens that used wood (19.4 ± 12.6) and charcoal (7.6 ± 6.5) than in those that used LPG (0.5 ± 0.6) or electricity (0.4 ± 0.6). Multivariable linear regression was conducted to generate predictive models for indoor PM2.5 and CO concentrations (predicted R2 = 0.837 and 0.822, respectively). This study provides baseline indoor air quality data for Paraguay and presents a multivariate statistical approach that could be used in future research and intervention programs. 相似文献
5.
Steven J. Hadeed Mary Kay O’Rourke Robert A. Canales Lorencita Joshweseoma Gregory Sehongva Morris Paukgana Emmanuel Gonzalez-Figueroa Modhi Alshammari Jefferey L. Burgess Robin B. Harris 《Indoor air》2021,31(6):2008-2019
Indoor and outdoor concentrations of PM2.5 were measured for 24 h during heating and non-heating seasons in a rural solid fuel burning Native American community. Household building characteristics were collected during the initial home sampling visit using technician walkthrough questionnaires, and behavioral factors were collected through questionnaires by interviewers. To identify seasonal behavioral factors and household characteristics associated with indoor PM2.5, data were analyzed separately by heating and non-heating seasons using multivariable regression. Concentrations of PM2.5 were significantly higher during the heating season (indoor: 36.2 μg/m3; outdoor: 22.1 μg/m3) compared with the non-heating season (indoor: 14.6 μg/m3; outdoor: 9.3 μg/m3). Heating season indoor PM2.5 was strongly associated with heating fuel type, housing type, indoor pests, use of a climate control unit, number of interior doors, and indoor relative humidity. During the non-heating season, different behavioral and household characteristics were associated with indoor PM2.5 concentrations (indoor smoking and/or burning incense, opening doors and windows, area of surrounding environment, building size and height, and outdoor PM2.5). Homes heated with coal and/or wood, or a combination of coal and/or wood with electricity and/or natural gas had elevated indoor PM2.5 concentrations that exceeded both the EPA ambient standard (35 μg/m3) and the WHO guideline (25 μg/m3). 相似文献
6.
In this paper, the chemical characterization of PM10 and PM2.5 mass concentrations emitted by heterogeneous traffic in Chennai city during monsoon, winter and summer seasons were analysed. The 24-h averages of PM10 and PM2.5 mass concentrations, showed higher concentrations during the winter season (PM10 = 98 μg/m3; PM2.5 = 74 μg/m3) followed by the monsoon (PM10 = 87 μg/m3; PM2.5 = 56 μg/m3) and summer (PM10 = 77 μg/m3; PM2.5 = 67 μg/m3) seasons. The assessment of 24-h average PM10 and PM2.5 concentrations was indicated as violation of the world health organization (WHO standard for PM10 = 50 μg/m3 and PM2.5 = 25 μg/m3) and Indian national ambient air quality standards (NAAQS for PM10 = 100 μg/m3 and PM2.5 = 60 μg/m3).The chemicals characterization of PM10 and PM2.5 samples (22 samples) for each season were made for water soluble ions using Ion Chromatography (IC) and trace metals by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) instrument. Results showed the dominance of crustal elements (Ca, Mg, Al, Fe and K), followed by marine aerosols (Na and K) and trace elements (Zn, Ba, Be, Ca, Cd, Co, Cr, Cu, Mn, Ni, Pb, Se, Sr and Te) emitted from road traffic in both PM10 and PM2.5 mass. The ionic species concentration in PM10 and PM2.5 mass consists of 47-65% of anions and 35-53% of cations with dominance of SO42− ions. Comparison of the metallic and ionic species in PM10 and PM2.5 mass indicated the contributions from sea and crustal soil emissions to the coarse particles and traffic emissions to fine particles. 相似文献
7.
Bonnie N. Young Maggie L. Clark Sarah Rajkumar Megan L. Benka‐Coker Annette Bachand Robert D. Brook Tracy L. Nelson John Volckens Stephen J. Reynolds Christian L'Orange Nicholas Good Kirsten Koehler Sebastian Africano Anibal B. Osorto Pinel Jennifer L. Peel 《Indoor air》2019,29(1):130-142
Growing evidence links household air pollution exposure from biomass cookstoves with elevated blood pressure. We assessed cross‐sectional associations of 24‐hour mean concentrations of personal and kitchen fine particulate matter (PM2.5), black carbon (BC), and stove type with blood pressure, adjusting for confounders, among 147 women using traditional or cleaner‐burning Justa stoves in Honduras. We investigated effect modification by age and body mass index. Traditional stove users had mean (standard deviation) personal and kitchen 24‐hour PM2.5 concentrations of 126 μg/m3 (77) and 360 μg/m3 (374), while Justa stove users’ exposures were 66 μg/m3 (38) and 137 μg/m3 (194), respectively. BC concentrations were similarly lower among Justa stove users. Adjusted mean systolic blood pressure was 2.5 mm Hg higher (95% CI, 0.7‐4.3) per unit increase in natural log‐transformed kitchen PM2.5 concentration; results were stronger among women of 40 years or older (5.2 mm Hg increase, 95% CI, 2.3‐8.1). Adjusted odds of borderline high and high blood pressure (categorized) were also elevated (odds ratio = 1.5, 95% CI, 1.0‐2.3). Some results included null values and are suggestive. Results suggest that reduced household air pollution, even when concentrations exceed air quality guidelines, may help lower cardiovascular disease risk, particularly among older subgroups. 相似文献
8.
Yuan Shao Lucy Kavi Meleah Boyle Lydia M. Louis Walkiria Pool Stephen B. Thomas Sacoby Wilson Ana M. Rule Lesliam Quiros-Alcala 《Indoor air》2021,31(4):1144-1153
Hairdressers are exposed to particulate matter (PM), a known air pollutant linked to adverse health effects. Still, studies on occupational PM exposures in hair salons are sparse. We characterized indoor air PM concentrations in three salons primarily serving an African/African American (AA) clientele, and three Dominican salons primarily serving a Latino clientele. We also assessed the performance of low-cost sensors (uRAD, Flow, AirVisual) by comparing them to high-end sensors (DustTrak) to conduct air monitoring in each salon over 3 days to quantify work shift concentrations of PM2.5, respirable PM (RPM), and PM10. We observed high spatial and temporal variability in 30-min time-weighted average (TWA) RPM concentrations (0.18–5518 μg/m3). Readings for the uRAD and AirVisual sensors were highly correlated with the DustTrak (R2 = 0.90–0.99). RPM 8-hour TWAs ranged from 18 to 383 µg/m3 for AA salons, and 9–2115 µg/m3 for Dominican salons. Upper 95th percentiles of daily RPM exposures ranged from 439 to 2669 µg/m3. The overall range of 30-min TWA PM2.5 and PM10 concentrations was 0.13–5497 and 0.36-,541 μg/m3, respectively. Findings suggest that hairdressers could be overexposed to RPM during an 8-hour shift. Additional comprehensive monitoring studies are warranted to further characterize temporal and spatial variability of PM exposures in this understudied occupational population. 相似文献
9.
Asian dust storms (ADS) originating from the arid deserts of Mongolia and China are a well-known springtime meteorological phenomenon throughout East Asia. The ventilation systems in office utilize air from outside and therefore it is necessary to understand how these dust storms affect the concentrations of PM2.5 and PM10 in both the indoor and outdoor air. We measured dust storm pollution particles in an office building using a direct-reading instrument (PC-2 Quartz Crystal Microbalance, QCM) that measured particle size and concentration every 10 min for 1 h, three times a day. A three-fold increase in the concentrations of PM2.5 and PM10 in the indoor and outdoor air was recorded during the dust storms. After adjusting for other covariates, autoregression models indicated that PM2.5 and PM10 in the indoor air increased significantly (21.7 μg/m3 and 23.0 μg/m3 respectively) during dust storms. The ventilation systems in high-rise buildings utilize air from outside and therefore the indoor concentrations of fine and coarse particles in the air inside the buildings are significantly affected by outside air pollutants, especially during dust storms. 相似文献
10.
Emissions from indoor biomass burning are a major public health concern in developing areas of the world. Less is known about indoor air quality, particularly airborne endotoxin, in homes burning biomass fuel in residential wood stoves in higher income countries. A filter‐based sampler was used to evaluate wintertime indoor coarse particulate matter (PM10‐2.5) and airborne endotoxin (EU/m3, EU/mg) concentrations in 50 homes using wood stoves as their primary source of heat in western Montana. We investigated number of residents, number of pets, dampness (humidity), and frequency of wood stove usage as potential predictors of indoor airborne endotoxin concentrations. Two 48‐h sampling events per home revealed a mean winter PM10‐2.5 concentration (± s.d.) of 12.9 (± 8.6) μg/m3, while PM2.5 concentrations averaged 32.3 (± 32.6) μg/m3. Endotoxin concentrations measured from PM10‐2.5 filter samples were 9.2 (± 12.4) EU/m3 and 1010 (± 1524) EU/mg. PM10‐2.5 and PM2.5 were significantly correlated in wood stove homes (r = 0.36, P < 0.05). The presence of pets in the homes was associated with PM10‐2.5 but not with endotoxin concentrations. Importantly, none of the other measured home characteristics was a strong predictor of airborne endotoxin, including frequency of residential wood stove usage. 相似文献
11.
V. Acevedo‐Bolton W. R. Ott K.‐C. Cheng R.‐T. Jiang N. E. Klepeis L. M. Hildemann 《Indoor air》2014,24(2):199-212
Few measurements of exposure to secondhand smoke (SHS) in close proximity to a smoker are available. Recent health studies have demonstrated an association between acute (<2 h) exposures to high concentrations of SHS and increased risk of cardiovascular and respiratory disease. We performed 15 experiments inside naturally ventilated homes and 16 in outdoor locations, each with 2–4 non‐smokers sitting near a cigarette smoker. The smoker's and non‐smokers' real‐time exposures to PM2.5 from SHS were measured by using TSI SidePak monitors to sample their breathing zones. In 87% of the residential indoor experiments, the smoker received the highest average exposure to SHS, with PM2.5 concentrations ranging from 50–630 μg/m3. During the active smoking period, individual non‐smokers sitting within approximately 1 m of a smoker had average SHS exposures ranging from negligible up to >160 μg/m3 of PM2.5. The average incremental exposure of the non‐smokers was higher indoors (42 μg/m3, n = 35) than outdoors (29 μg/m3, n = 47), but the overall indoor and outdoor frequency distributions were similar. The 10‐s PM2.5 averages during the smoking periods showed great variability, with multiple high concentrations of short duration (microplumes) both indoors and outdoors. 相似文献
12.
Christos Halios Mat Santamouris Maria Kapsalaki Dimitris Tsakos 《The Science of the total environment》2009,407(17):4894-4901
The aim of the present work is to study the occupants' exposure to fine particulate concentrations in ten nightclubs (NCs) in Athens, Greece. Measurements of PM1 and PM2.5 were made in the outdoor and indoor environment of each NC. The average indoor PM1 and PM2.5 concentrations were found to be 181.77 μg m− 3 and 454.08 μg m− 3 respectively, while the corresponding outdoor values were 11.04 μg m− 3 and 32.19 μg m− 3. Ventilation and resuspension rates were estimated through consecutive numerical experiments with an indoor air quality model and were found to be remarkably lower than the minimum values recommended by national standards. The relative effects of the ventilation and smoking on the occupants' exposures were examined using multiple regression techniques. It was found that given the low ventilation rates, the effect of smoking as well as the occupancy is of the highest importance. Numerical evaluations showed that if the ventilation rates were at the minimum values set by national standards, then the indoor exposures would be reduced at the 70% of the present exposure values. 相似文献
13.
H. Salje E. S. Gurley N. Homaira P. K. Ram R. Haque W. Petri W. J. Moss S. P. Luby P. Breysse E. Azziz‐Baumgartner 《Indoor air》2014,24(2):213-220
Exposure to particulate matter (PM2.5) from the burning of biomass is associated with increased risk of respiratory disease. In Dhaka, Bangladesh, households that do not burn biomass often still experience high concentrations of PM2.5, but the sources remain unexplained. We characterized the diurnal variation in the concentrations of PM2.5 in 257 households and compared the risk of experiencing high PM2.5 concentrations in biomass and non‐biomass users. Indoor PM2.5 concentrations were estimated every minute over 24 h once a month from April 2009 through April 2010. We found that households that used gas or electricity experienced PM2.5 concentrations exceeding 1000 μg/m3 for a mean of 35 min within a 24‐h period compared with 66 min in biomass‐burning households. In both households that used biomass and those that had no obvious source of particulate matter, the probability of PM2.5 exceeding 1000 μg/m3 were highest during distinct morning, afternoon, and evening periods. In such densely populated settings, indoor pollution in clean fuel households may be determined by biomass used by neighbors, with the highest risk of exposure occurring during cooking periods. Community interventions to reduce biomass use may reduce exposure to high concentrations of PM2.5 in both biomass and non‐biomass using households. 相似文献
14.
Unexpected increase in indoor pollutants after the introduction of a smoke‐free policy in a correctional center
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C. He L. D. Knibbs Q. Tran H. Wang R. Laiman B. Wang Y. Gu L. Morawska 《Indoor air》2016,26(4):623-633
Correctional centers (prisons) are one of the few non‐residential indoor environments where smoking is still permitted. However, few studies have investigated indoor air quality (IAQ) in these locations. We quantified the level of inmate and staff exposure to secondhand smoke, including particle number (PN) count, and we assessed the impact of the smoking ban on IAQ. We performed measurements of indoor and outdoor PM2.5 and PN concentrations, personal PN exposure levels, volatile organic compounds (VOCs), and nicotine both before and after a complete indoor smoking ban in an Australian maximum security prison. Results show that the indoor 24‐h average PM2.5 concentrations ranged from 6 (±1) μg/m3 to 17 (±3) μg/m3 pre‐ban. The post‐ban levels ranged from 7 (±2) μg/m3 to 71 (±43) μg/m3. While PM2.5 concentrations decreased in one unit post‐ban, they increased in the other two units. Similar post‐ban increases were also observed in levels of PN and VOCs. We describe an unexpected increase of indoor pollutants following a total indoor smoking ban in a prison that was reflected across multiple pollutants that are markers of smoking. We hypothesise that clandestine post‐ban smoking among inmates may have been the predominant cause. 相似文献
15.
Karin Rosenkilde Laursen Berit Brøndum Rasmussen Bernadette Rosati Vibeke Heitmann Gutzke Kirsten Østergaard Peter Ravn Søren Kenneth Kjærgaard Merete Bilde Marianne Glasius Torben Sigsgaard 《Indoor air》2021,31(6):1993-2007
Particulate matter is linked to adverse health effects, however, little is known about health effects of particles emitted from typical indoor sources. We examined acute health effects of short-term exposure to emissions from cooking and candles among asthmatics. In a randomized controlled double-blinded crossover study, 36 young non-smoking asthmatics attended three exposure sessions lasting 5 h: (a) air mixed with emissions from cooking (fine particle mass concentration): (PM2.5: 96.1 μg/m3), (b) air mixed with emissions from candles (PM2.5: 89.8 μg/m3), and c) clean filtered air (PM2.5: 5.8 μg/m3). Health effects (spirometry, fractional exhaled Nitric Oxide [FeNO], nasal volume and self-reported symptoms) were evaluated before exposure start, then 5 and 24 h after. During exposures volatile organic compounds (VOCs), particle size distributions, number concentrations and optical properties were measured. Generally, no statistically significant changes were observed in spirometry, FeNO, or nasal volume comparing cooking and candle exposures to clean air. In males, nasal volume and FeNO decreased after exposure to cooking and candles, respectively. Participants reported additional and more pronounced symptoms during exposure to cooking and candles compared to clean air. The results indicate that emissions from cooking and candles exert mild inflammation in asthmatic males and decrease comfort among asthmatic males and females. 相似文献
16.
Karoline K. Barkjohn Christina Norris Xiaoxing Cui Lin Fang Tongshu Zheng James J. Schauer Zhen Li Yinping Zhang Marilyn Black Junfeng Zhang Michael H. Bergin 《Indoor air》2021,31(1):74-87
Portable air cleaners are increasingly used in polluted areas in an attempt to reduce human exposure; however, there has been limited work characterizing their effectiveness at reducing exposure. With this in mind, we recruited forty-three children with asthma from suburban Shanghai and deployed air cleaners (with HEPA and activated carbon filters) in their bedrooms. During both 2-week filtration and non-filtration periods, low-cost PM2.5 and O3 air monitors were used to measure pollutants indoors, outdoors, and for personal exposure. Indoor PM2.5 concentrations were reduced substantially with the use of air cleaners, from 34 ± 17 to 10 ± 8 µg/m3, with roughly 80% of indoor PM2.5 estimated to come from outdoor sources. Personal exposure to PM2.5 was reduced from 40 ± 17 to 25 ± 14 µg/m3. The more modest reductions in personal exposure and high contribution of outdoor PM2.5 to indoor concentrations highlight the need to reduce outdoor PM2.5 and/or to clean indoor air in multiple locations. Indoor O3 concentrations were generally low (mean = 8±4 ppb), and no significant difference was seen by filtration status. The concentrations of pollutants and the air cleaner effectiveness were highly variable over time and across homes, highlighting the usefulness of real-time air monitors for understanding individual exposure reduction strategies. 相似文献
17.
Maternal exposure to carbon monoxide and fine particulate matter during pregnancy in an urban Tanzanian cohort
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B. J. Wylie Y. Kishashu E. Matechi Z. Zhou B. Coull A. I. Abioye K. L. Dionisio F. Mugusi Z. Premji W. Fawzi R. Hauser M. Ezzati 《Indoor air》2017,27(1):136-146
Low birthweight contributes to as many as 60% of all neonatal deaths; exposure during pregnancy to household air pollution has been implicated as a risk factor. Between 2011 and 2013, we measured personal exposures to carbon monoxide (CO) and fine particulate matter (PM2.5) in 239 pregnant women in Dar es Salaam, Tanzania. CO and PM2.5 exposures during pregnancy were moderately high (geometric means 2.0 ppm and 40.5 μg/m3); 87% of PM2.5 measurements exceeded WHO air quality guidelines. Median and high (75th centile) CO exposures were increased for those cooking with charcoal and kerosene versus kerosene alone in quantile regression. High PM2.5 exposures were increased with charcoal use. Outdoor cooking reduced median PM2.5 exposures. For PM2.5, we observed a 0.15 kg reduction in birthweight per interquartile increase in exposure (23.0 μg/m3) in multivariable linear regression; this finding was of borderline statistical significance (95% confidence interval 0.30, 0.00 kg; P = 0.05). PM2.5 was not significantly associated with birth length or head circumference nor were CO exposures associated with newborn anthropometrics. Our findings contribute to the evidence that exposure to household air pollution, and specifically fine particulate matter, may adversely affect birthweight. 相似文献
18.
Indoor particle number and PM2.5 concentrations were investigated in a radio station surrounded by busy roads. Two extensive field measurement campaigns were conducted to determine the critical parameters affecting indoor air quality. The results indicated that indoor particle number and PM2.5 concentrations were governed by outdoor air, and were significantly affected by the location of air intake and design of HVAC system. Prior to the upgrade of the HVAC system and relocation of the air intake, the indoor median particle number concentration was 7.4×103 particles/cm3 and the median PM2.5 concentration was 7 μg/m3. After the relocation of air intake and the redesign of the HVAC system, the indoor particle number concentration was between 2.3×103 and 3.4×103 particles/cm3, with a median value of 2.7×103 particles/cm3, and the indoor PM2.5 concentration was in the range of 3–5 μg/m3, with a median value of 4 μg/m3. By relocating the air intake of the HVAC, the outdoor particle number and PM2.5 concentrations near the air intake were reduced by 35% and 55%, respectively. In addition, with the relocation of air intake and the redesign of the HVAC system, the particle number penetration rate was reduced from 42% to 14%, and the overall filtration efficiency of the HVAC system (relocation of air intake, pre-filter, AHU and particle losses in the air duct) increased from 58% to 86%. For PM2.5, the penetration rate after the upgrade was approximately 18% and the overall filtration efficiency was 82%. This study demonstrates that by using a comprehensive approach, including the assessment of outdoor conditions and characterisation of ventilation and filtration parameters, satisfactory indoor air quality can be achieved, even for those indoor environments facing challenging outdoor air conditions. 相似文献
19.
More than half the world's population use biomass fuels as a household energy source and, hence, face significant exposure to a number of air pollutants. In Pakistan about 90% of rural households and 22% of urban households use biomass fuels. In order to assess the levels of NO2 in the residential micro-environment, two sampling campaigns were carried out at different times of the year (summer and winter) at an urban and two rural sites during 2005 and 2007. Rural site I used biomass fuels while natural gas was utilized at rural site II and the urban site. In winter NO2 concentrations at all three sites were higher in the kitchens than living rooms and outdoors. ANOVA showed that, although, there was a significant difference among NO2 concentrations in the kitchens, living rooms and courtyards, at all the three sites, there was no significant different between kitchens using biomass fuels and natural gas. During the summer NO2 levels fell sharply at both rural sites (from 256 μg/m3 and 242 μg/m3 to 51 μg/m3 and 81 μg/m3). However at the urban site the mean levels were slightly higher in summer (234 μg/m3) than in winter (218 μg/m3). The considerable seasonal variation at the rural sites was due to a shift of indoor kitchens to open outdoor kitchens at rural site I and more ventilation at rural site II during summer. There was no significant difference between kitchens using biomass (site I) or natural gas (site II), however the kitchens at rural site II and urban site showed a significant difference. Overall fuel selection showed no significant effect on NO2 levels. However the NO2 concentrations may pose a significant threat to the health of people, especially women and children. 相似文献
20.
Yu-yan Yang Lin Fan Jiao Wang Yuan-duo Zhu Xu Li Xin-qi Wang Xu Yan Li Li Yu-jing Zhang Wen-jing Yang Xiao-yuan Yao Xian-liang Wang 《Indoor air》2021,31(5):1391-1401
Household fine particulate matter (PM2.5) pollution greatly impacts residents' health. To explore the current national situation of household PM2.5 pollution in China, a study was conducted based on literature published from 1998 to 2018. After extracting data from the literature in conformity with the requirements, the nationwide household-weighted mean concentration of household PM2.5 (HPL) was calculated. Subgroup analyses of spatial, geographic, and temporal differences were also done. The estimated overall HPL in China was 132.2 ± 117.7 μg/m3. HPL in the rural area (164.3 ± 104.5 μg/m3) was higher than that in the urban area (123.9 ± 122.3 μg/m3). For HPLs of indoor sampling sites, the kitchen was the highest, followed by the bedroom and living room. There were significant differences of geographic distributions. The HPLs in the South were higher than the North in four seasons. The inhaled dose of household PM2.5 among school-age children differed from provinces with the highest dose up to 5.9 μg/(kg·d). Countermeasures should be carried out to reduce indoor pollution and safeguard health urgently. 相似文献