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Potential factors that impact the radon level and the prediction of ambient dose equivalent rates of indoor microenvironments

Ali MYM, Hanafiah MM, Khan MF

Sci Total Environ, 2018 Jun 01;626:1-10.
PMID: 29331833 DOI: 10.1016/j.scitotenv.2018.01.080

This study aimed to measure the equilibrium equivalent radon (EECRn) concentration in an old building (Building-1) and a new building (Building-2) with mechanical ventilation and a natural ventilation system, respectively. Both buildings were located at the campus of University Kebangsaan Malaysia. The concentration of indoor radon was measured at 25 sampling stations using a radon detector model DOSEman PRO. The sampling was conducted for 8 h to represent daily working hours. A correlation of the radon concentration was made with the annual inhalation dose of the occupants at the indoor stations. The equilibrium factor and the annual effective dose on the lung cancer risks of each occupant were calculated at each sampling station. The average equilibrium equivalent radon measured in Building-1 and Building-2 was 2.33 ± 0.99 and 3.17 ± 1.74 Bqm-3, respectively. The equilibrium factor for Building 1 ranged from 0.1053 to 0.2273, and it ranged from 0.1031 to 0.16 for Building 2. The average annual inhalation doses recorded at Building-1 and Building-2 were 0.014 ± 0.005 mSv y-1and 0.020 ± 0.013 mSv y-1, respectively. The annual effective dose for Building-1 was 0.034 ± 0.012 mSv y-1, and it was 0.048 ± 0.031 mSv y-1for Building-2. The values of equilibrium equivalent radon concentration for both buildings were below the standard recommended by the International Commission on Radiological Protection (ICRP). However, people may have different radon tolerance levels. Therefore, the inhalation of the radon concentration can pose a deleterious health effect for people in an indoor environment.

Matched MeSH terms: Air Pollutants, Radioactive
Fulltext Forecasting ozone concentration levels using Box-Jenkins ARIMA modelling and artificial neural networks: a comparative study

Norhashidah Awang, Ng, Kar Yong, Soo, Yin Hoeng

MATEMATIKA, 2017;33(2):119-130.
MyJurnal

An accurate forecasting of tropospheric ozone (O3) concentration is benefi-
cial for strategic planning of air quality. In this study, various forecasting techniques are
used to forecast the daily maximum O3 concentration levels at a monitoring station
in the Klang Valley, Malaysia. The Box-Jenkins autoregressive integrated movingaverage
(ARIMA) approach and three types of neural network models, namely, backpropagation
neural network, Elman recurrent neural network and radial basis function
neural network are considered. The daily maximum data, spanning from 1 January
2011 to 7 August 2011, was obtained from the Department of Environment, Malaysia.
The performance of the four methods in forecasting future values of ozone concentrations
is evaluated based on three criteria, which are root mean square error (RMSE),
mean absolute error (MAE) and mean absolute percentage error (MAPE). The findings
show that the Box-Jenkins approach outperformed the artificial neural network
methods.

Matched MeSH terms: Air Pollution
Fulltext Ornamental potted plant as air bio-filters for indoor environments

Mohd Mahathir Suhaimi Shamsuri, Leman, A.M., Azian Hariri, Azizi Afandi

Journal of Occupational Safety and Health, 2016;13(2):1-8.
MyJurnal

The cultivation of indoor plants in indoor environment has become a topic of interest among researchers worldwide for its
potential to improve indoor air quality (IAQ). However, the adaptations of environmental factor of each plant need to be investigated
to correspond with the native environment. The study investigate the capability of plants selected to live indoor. Before experiment was
conducted, all plants selected were assimilated with indoor environment for two months. Photosynthesis proses in this experiment will
be a guidance to determine the comparative for every plant. The portable photosynthesis system equipment (LI-COR 6400) was used to
determine the level of photosynthesis rate for each of plants. Accordingly, among of all plants tested, Spider Plant showed less effective
to be grown with indoor environment by the rate of photosynthesis value up to -0.15. Moreover, light compensation point (LCP) of
Spider Plant also indicated the light intensity consumption was 2960 lux which is extremely higher than 300 lux. As a conclusion, only
six plants in this study which are Anthurium, Dumb Cane, Golden Pothos, Kadaka Fern, Prayer Plant, and Syngonium are able to
survive with indoor environment. In the next stage of study, this six plants may give good results to enhance the IAQ.

Matched MeSH terms: Air Pollution, Indoor
Fulltext Assessment of radon concentrations on highland areas in Malaysia

Ismail Sulaiman, Khairuddin Mohamad Kontol, Faizal Azrin Abdul Razalim

Jurnal Sains Nuklear Malaysia, 2018;30(1):46-52.
MyJurnal

The indoor and outdoor radon concentrations in Cameron Highlands (Peninsular Malaysia) and Ranau (East Malaysia) were measured. The measurements were carried out using passive method based on CR-39 solid state nuclear track detector (SSNTD) (for indoor measurements in Cameron Highlands) and active method using continuous radon/thoron progeny monitor (for indoor and outdoor measurements in Ranau and outdoor measurements in Cameron Highlands). The mean indoor radon concentrations in Cameron Highlands and Ranau were 50 Bqm-3 and 1.5 Bqm-3, respectively. The mean indoor radon concentration in Cameron Highlands was slightly higher compare to the world average. The maximum value recorded was 97 Bqm-3 which is almost similar to WHO reference level. The mean outdoor radon concentrations in Cameron Highlands and Ranau were 7.4 Bqm-3and 1.7 Bqm-3, respectively. The outdoor concentrations were low and comparable to world outdoor average.

Matched MeSH terms: Air Pollutants, Radioactive
Fulltext Preparation, Characterization, and Performance Evaluation of Polysulfone Hollow Fiber Membrane with PEBAX or PDMS Coating for Oxygen Enhancement Process

Chong KC, Lai SO, Lau WJ, Thiam HS, Ismail AF, Roslan RA

Polymers (Basel), 2018 Jan 28;10(2).
PMID: 30966162 DOI: 10.3390/polym10020126

Air pollution is a widely discussed topic amongst the academic and industrial spheres as it can bring adverse effects to human health and economic loss. As humans spend most of their time at the office and at home, good indoor air quality with enriched oxygen concentration is particularly important. In this study, polysulfone (PSF) hollow fiber membranes fabricated by dry-jet wet phase inversion method were coated by a layer of polydimethylsiloxane (PDMS) or poly(ether block amide) (PEBAX) at different concentrations and used to evaluate their performance in gas separation for oxygen enrichment. The surface-coated membranes were characterized using SEM and EDX to determine the coating layer thickness and surface chemical properties, respectively. Results from the gas permeation study revealed that the PSF membrane coated with PDMS offered higher permeance and selectivity compared to the membrane coated with PEBAX. The best performing PDMS-coated membrane demonstrated oxygen and nitrogen gas permeance of 18.31 and 4.01 GPU, respectively with oxygen/nitrogen selectivity of 4.56. Meanwhile, the PEBAX-coated membrane only showed 12.23 and 3.11 GPU for oxygen and nitrogen gas, respectively with a selectivity of 3.94. It can be concluded the PDMS coating is more promising for PSF hollow fiber membrane compared to the PEBAX coating for the oxygen enrichment process.

Matched MeSH terms: Air Pollution, Indoor
A patient with massive cerebral arterial air embolism

Chan CBT, Loo LK, Manocha AB

Med J Malaysia, 2019 Jun;74(3):226-228.
PMID: 31256178

Cerebral air embolism is potentially a catastrophic event that occurs as a consequence of air entry into the vasculature. We report a mechanically ventilated 72-year-old woman who underwent multiple procedures during intensive care stay with few possible sources of emboli postulated. We also discuss regarding the preventive measures to minimise the risk of air embolism.

Matched MeSH terms: Embolism, Air
Finned spacer for efficient membrane fouling control in produced water filtration

Rahmawati R, Bilad MR, Laziz AM, Nordin NAHM, Jusoh N, Putra ZA, et al.

J Environ Manage, 2019 Nov 01;249:109359.
PMID: 31404857 DOI: 10.1016/j.jenvman.2019.109359

Membrane based technologies are highly reliable for water and wastewater treatment, including for removal of total oil and grease from produced water. However, performances of the pressure driven processes are highly restricted by membrane fouling and the application of traditional air bubbling system is limited by their low shear stress due to poor contacts with the membrane surface. This study develops and assesses a novel finned spacer, placed in between vertical panel, for membrane fouling control in submerged plate-and-frame module system for real produced water filtration. Results show that permeability of the panel is enhanced by 87% from 201 to 381 L/(m2 h bar). The spacer system can be operated in switching mode to accommodate two-sided panel aeration. This leads to panel permeability increment by 22% higher than the conventional vertical system. The mechanisms of finned spacer in encouraging the flow trajectory was proven by visual observation and flow simulation. The fins alter the air bubbles flow trajectory toward the membrane surface to effectively scour-off the foulant. Overall results demonstrate the efficacy of the developed spacer in projecting the air bubble trajectory toward the membrane surface and thus significantly enhances membrane panel productivity.

Matched MeSH terms: Air
Discussion. Pollution problems of the Philippines

Med J Malaysia, 1974 Dec;29(2):125.
PMID: 4282397
Matched MeSH terms: Air Pollution
Compliances of airborne microbe in different phases of building commisioning

Ahmad Sayuti Zainal Abidin, Leman, A.M., Nor Mohd Razif Noraini

Journal of Occupational Safety and Health, 2012;9(3):39-44.
MyJurnal

This study intended to investigate the level on airborne microbe in indoor air for new constructed building. It was divided by three different phase of building commissioning in Bandar Baru Bangi, Selangor. The first phase of the sampling was carried out after the building fully handed over from the main contractor to the building owner. Second phase of the sampling take place after the building is equipped with furniture. Phase three sampling is conducted after one month of building occupancy. Airborne microbes’ concentrations were determined by using a single stage impactor (Biosampler) as per requirement of National Institute of Occupational Safety and Health (NIOSH) method, NIOSH Manual Analytical Method MAM 0800. The total concentration of airborne bacteria and fungi were average to 641 and 38 CFU/m³ in the first phase, 133 and 117 CFU/m³ in the second phase, and 389 and 52 CFU/m³ in the third phase. These findings indicate that although a new constructed building should be having a significant background level of airborne microbe (total bacteria and total fungi). The building owner should be aware to their indoor air status to protect the occupant from the safety and health problem (risk) especially for ventilated building.

Matched MeSH terms: Air Pollution, Indoor
Fulltext Using computational fluid dynamics in the determination of solar collector orientation and stack height of a solar induced ventilation prototype

Yusoff, W. F. M., Sapian, A. R., Salleh, E., Adam, N. M., Hamzah, Z., Mamat, M. H. H.

Pertanika Journal of Science & Technology, 2014;22(1):273-288.
MyJurnal

Stack ventilation in the hot and humid climate is inherently inefficient due to minimal air temperature differences between indoor and outdoor environment of a naturally ventilated building. Solar induced ventilation is a viable alternative in enhancing this stack ventilation. This paper aims to demonstrate investigations on the effective solar collector orientation and stack height for a solar induced ventilation prototype that utilizes roof solar collector and vertical stack. The orientation of the solar collector is significant as it determines the amount of solar radiation absorbed by the solar collector. Meanwhile, the height of the vertical stack influences the creation of the stack pressure in inducing air movement. Investigations were executed using a simulation modelling software called FloVENT. The validation of the simulation modelling against physical experiment indicated a good agreement between these two results. Analyses were executed on the air temperature increments inside the solar collector. A high increment of the air temperature resulted in the effective orientation. Meanwhile, the air temperature and mass flow rate of the various heights of the vertical stack were also analyzed. The findings concluded that the recommended orientation for the prototype’s solar collector is the west-facing orientation. It was also found that the higher the vertical stack, the lower the air temperature inside the stack would be, but with greater induced mass flow rate.

Matched MeSH terms: Air Movements
Fulltext Handling overdispersion in mortality data in time-series epidemiologic reserch using SAS software

Wan Rozita, W.M., Rasimah, A., Mazrura, S., Lim, K.H., Thana, S.

Malaysian Journal of Public Health Medicine, 2010;10(2):6-15.
MyJurnal

Analysis of count event data such as mortality cases, were often modelled using Poisson regression model. Maximum likelihood procedures were used by using SAS software to estimate the model parameters of a Poisson regression model. However, the Negative Binomial distribution has been widely suggested as the alternative to the Poisson when there is proof of overdispersion phenomenon. We modelled the mortality cases as the dependent variable using Poisson and Negative Binomial regression and compare both of the models. The procedures were done in SAS by using the function PROC GENMOD. The results showed that the mortality data in Poisson regression exhibit large ratio values between deviance to degree of freedom which indicate model misspecification or overdispersion. This large ratio was found to be reduced in Negative Binomial regression. The Normal probability plot of Pearson residual confirmed that the Negative Binomial regression is a better model than Poisson regression in modelling the mortality data. The objective of this study is to compare the goodness of fit of Poisson regression model and Negative Binomial regression model in the application of air pollution epidemiologic time series study by using SAS software.

Matched MeSH terms: Air Pollution
Transboundary smoke haze pollution in Malaysia: inpatient health impacts and economic valuation

Othman J, Sahani M, Mahmud M, Ahmad MK

Environ Pollut, 2014 Jun;189:194-201.
PMID: 24682070 DOI: 10.1016/j.envpol.2014.03.010

This study assessed the economic value of health impacts of transboundary smoke haze pollution in Kuala Lumpur and adjacent areas in the state of Selangor, Malaysia. Daily inpatient data from 2005, 2006, 2008, and 2009 for 14 haze-related illnesses were collected from four hospitals. On average, there were 19 hazy days each year during which the air pollution levels were within the Lower Moderate to Hazardous categories. No seasonal variation in inpatient cases was observed. A smoke haze occurrence was associated with an increase in inpatient cases by 2.4 per 10,000 populations each year, representing an increase of 31 percent from normal days. The average annual economic loss due to the inpatient health impact of haze was valued at MYR273,000 ($91,000 USD).

Matched MeSH terms: Air Pollutants/analysis*; Air Pollution/statistics & numerical data*
Selection of metal oxides in the preparation of rice husk ash (RHA)/CaO sorbent for simultaneous SO2 and NO removal

Dahlan I, Lee KT, Kamaruddin AH, Mohamed AR

J Hazard Mater, 2009 Jul 30;166(2-3):1556-9.
PMID: 19147280 DOI: 10.1016/j.jhazmat.2008.12.028

In this work, the removal of SO(2) and NO from simulated flue gas from combustion process was investigated in a fixed-bed reactor using rice husk ash (RHA)/CaO-based sorbent. Various metal precursors were used in order to select the best metal impregnated over RHA/CaO sorbents. The results showed that RHA/CaO sorbents impregnated with CeO(2) had the highest sorption capacity among other impregnated metal oxides for the simultaneous removal of SO(2) and NO. Infrared spectroscopic results indicated the formation of both sulfate (SO(4)(2-)) and nitrate (NO(3)(-)) species due to the catalytic role played by CeO(2). Apart from that, the catalytic activity of the RHA/CaO/CeO(2) sorbent was found to be closely related to its physical properties (specific surface area, total pore volume and average pore diameter).

Matched MeSH terms: Air Pollutants/isolation & purification; Air Pollution/prevention & control*
Understanding selected trace elements behavior in a coal-fired power plant in Malaysia for assessment of abatement technologies

Mokhtar MM, Taib RM, Hassim MH

J Air Waste Manag Assoc, 2014 Aug;64(8):867-78.
PMID: 25185389

The Proposed New Environmental Quality (Clean Air) Regulation 201X (Draft), which replaces the Malaysia Environmental Quality (Clean Air) 1978, specifies limits to additional pollutants from power generation using fossil fuel. The new pollutants include Hg, HCl, and HF with limits of 0.03, 100, and 15 mg/N-m3 at 6% O2, respectively. These pollutants are normally present in very small concentrations (known as trace elements [TEs]), and hence are often neglected in environmental air quality monitoring in Malaysia. Following the enactment of the new regulation, it is now imperative to understand the TEs behavior and to assess the capability of the existing abatement technologies to comply with the new emission limits. This paper presents the comparison of TEs behavior of the most volatile (Hg, Cl, F) and less volatile (As, Be, Cd, Cr, Ni, Se, Pb) elements in subbituminous and bituminous coal and coal combustion products (CCP) (i.e., fly ash and bottom ash) from separate firing of subbituminous and bituminous coal in a coal-fired power plant in Malaysia. The effect of air pollution control devices configuration in removal of TEs was also investigated to evaluate the effectiveness of abatement technologies used in the plant. This study showed that subbituminous and bituminous coals and their CCPs have different TEs behavior. It is speculated that ash content could be a factor for such diverse behavior In addition, the type of coal and the concentrations of TEs in feed coal were to some extent influenced by the emission of TEs in flue gas. The electrostatic precipitator (ESP) and seawater flue gas desulfurization (FGD) used in the studied coal-fired power plant were found effective in removing TEs in particulate and vapor form, respectively, as well as complying with the new specified emission limits. Implications: Coals used by power plants in Peninsular Malaysia come from the same supplier (Tenaga Nasional Berhad Fuel Services), which is a subsidiary of the Malaysia electricity provider (Tenaga Nasional Berhad). Therefore, this study on trace elements behavior in a coal-fired power plant in Malaysia could represent emission from other plants in Peninsular Malaysia. By adhering to the current coal specifications and installation of electrostatic precipitator (ESP) and flue gas desulfurization, the plants could comply with the limits specified in the Malaysian Department of Environment (DOE) Scheduled Waste Guideline for bottom ash and fly ash and the Proposed New Environmental Quality (Clean Air) Regulation 201X (Draft).

Matched MeSH terms: Air Pollutants/analysis*; Air Pollution/prevention & control*
Fulltext Indoor air quality and respiratory health among malay preschool children in Selangor

Rawi NA, Jalaludin J, Chua PC

Biomed Res Int, 2015;2015:248178.
PMID: 25984527 DOI: 10.1155/2015/248178

Indoor air quality (IAQ) has been the object of several studies due to its adverse health effects on children. Methods. A cross-sectional comparative study was carried out among Malay children in Balakong (2 studied preschools) and Bangi (2 comparative preschools), Selangor, with the aims of determining IAQ and its association with respiratory health. 61 and 50 children aged 5-6 years were selected as studied and comparative groups. A questionnaire was used to obtain an exposure history and respiratory symptoms. Lung function test was carried out. IAQ parameters obtained include indoor concentration of particulate matter (PM), volatile organic compounds (VOCs), carbon monoxide (CO), carbon dioxide (CO2), temperature, air velocity (AV), and relative humidity. Results. There was a significant difference between IAQ in studied and comparative preschools for all parameters measured (P < 0.001) except for CO2 and AV. Studied preschools had higher PM and CO concentration. FVC, FEV1, FVC% and FEV1% predicted values were significantly lower among studied group. Exposures to PM, VOCs, and CO were associated with wheezing. Conclusion. The finding concluded that exposures to poor IAQ might increase the risk of getting lung function abnormality and respiratory problems among study respondents.

Matched MeSH terms: Air Pollutants/analysis; Air Pollution, Indoor/adverse effects*
Fulltext Occurrence of cymothoid isopod from Miri, East Malaysian marine fishes

Anand Kumar A, Rameshkumar G, Ravichandran S, Priya ER, Nagarajan R, Leng AG

J Parasit Dis, 2015 Jun;39(2):206-10.
PMID: 26064001 DOI: 10.1007/s12639-013-0320-7

To identify the isopod parasite, which has been recorded from Miri, East Malaysian marine fishes. During the present study, four cymothoid isopods are reported three genera, including Cymothoa eremita, Lobothorax typus, Nerocila longispina and Nerocila loveni. Nerocila longispina and N. loveni are also previously reported from Malaysia and two additional cymothoids C. eremita and L. typus are reported for the first record of Miri coast, East Malaysia. New hosts were identified for N. loveni on Chirocentrus dorab for the first time in the world fauna. The Parasitological indexes were calculated. The site of attachment of the parasites on their hosts was also observed. These parasites can cause the damage in gill, eye and internal organ including swim bladder. Marine fish parasitology is a rapidly developing field of aquatic science.

Matched MeSH terms: Air Sacs
Second-hand smoke in public spaces: how effective has partial smoke-free legislation been in Malaysia?

Abidin EZ, Hashim Z, Semple S

Asian Pac J Cancer Prev, 2013;14(11):6845-50.
PMID: 24377615

BACKGROUND: This study was performed to gather data on second-hand smoke (SHS) concentrations in a range of public venues following the implementation of partial Smoke-Free Legislation in Malaysia in 2004.
MATERIALS AND METHODS: PM2.5 was measured as a marker of SHS levels in a total of 61 restaurants, entertainment centres, internet cafes and pubs in Kuala Lumpur, Malaysia.
RESULTS: Under the current smoke-free laws smoking was prohibited in 42 of the 61 premises. Active smoking was observed in nearly one-third (n=12) of these. For premises where smoking was prohibited and no active smoking observed, the mean (standard deviation) indoor PM2.5 concentration was 33.4 (23.8) μg/m3 compared to 187.1 (135.1) μg/m3 in premises where smoking was observed The highest mean PM2.5 was observed in pubs [361.5 (199.3) μg/m3].
CONCLUSIONS: This study provides evidence of high levels of SHS across a range of hospitality venues, including about one-third of those where smoking is prohibited, despite 8 years of smoke-free legislation. Compliance with the legislation appeared to be particularly poor in entertainment centres and internet cafes. Workers and non-smoking patrons continue to be exposed to high concentrations of SHS within the hospitality industry in Malaysia and there is an urgent need for increased enforcement of existing legislation and consideration of more comprehensive laws to protect health.

Matched MeSH terms: Air Pollution, Indoor/analysis*; Air Pollution, Indoor/legislation & jurisprudence; Air Pollution, Indoor/prevention & control
Fulltext Endotoxin, ergosterol, fungal DNA and allergens in dust from schools in Johor Bahru, Malaysia- associations with asthma and respiratory infections in pupils

Norbäck D, Markowicz P, Cai GH, Hashim Z, Ali F, Zheng YW, et al.

PLoS One, 2014;9(2):e88303.
PMID: 24523884 DOI: 10.1371/journal.pone.0088303

There are few studies on associations between respiratory health and allergens, fungal and bacterial compounds in schools in tropical countries. The aim was to study associations between respiratory symptoms in pupils and ethnicity, chemical microbial markers, allergens and fungal DNA in settled dust in schools in Malaysia. Totally 462 pupils (96%) from 8 randomly selected secondary schools in Johor Bahru, Malaysia, participated. Dust was vacuumed from 32 classrooms and analysed for levels of different types of endotoxin as 3-hydroxy fatty acids (3-OH), muramic acid, ergosterol, allergens and five fungal DNA sequences. Multiple logistic regression was applied. Totally 13.1% pupils reported doctor's diagnosed asthma, 10.3% wheeze and 21.1% pollen or pet allergy. Indian and Chinese children had less atopy and asthma than Malay. Carbon dioxide levels were low (380-690 ppm). No cat (Fel d1), dog (Can f 1) or horse allergens (Ecu cx) were detected. The levels of Bloomia tropicalis (Blo t), house dust mite allergens (Der p 1, Der f 1, Der m 1) and cockroach allergens (Per a 1 and Bla g 1) were low. There were positive associations between levels of Aspergillus versicolor DNA and daytime breathlessness, between C14 3-OH and respiratory infections and between ergosterol and doctors diagnosed asthma. There were negative (protective) associations between levels of C10 3-OH and wheeze, between C16 3-OH and day time and night time breathlessness, between cockroach allergens and doctors diagnosed asthma. Moreover there were negative associations between amount of fine dust, total endotoxin (LPS) and respiratory infections. In conclusion, endotoxin at school seems to be mainly protective for respiratory illness but different types of endotoxin could have different effects. Fungal contamination measured as ergosterol and Aspergillus versicolor DNA can be risk factors for respiratory illness. The ethnical differences for atopy and asthma deserve further attention.

Matched MeSH terms: Air Pollutants/analysis; Air Pollution, Indoor/analysis
Thermal sensations and comfort investigations in transient conditions in tropical office

Dahlan ND, Gital YY

Appl Ergon, 2016 May;54:169-76.
PMID: 26851476 DOI: 10.1016/j.apergo.2015.12.008

The study was done to identify affective and sensory responses observed as a result of hysteresis effects in transient thermal conditions consisting of warm-neutral and neutral - warm performed in a quasi-experiment setting. Air-conditioned building interiors in hot-humid areas have resulted in thermal discomfort and health risks for people moving into and out of buildings. Reports have shown that the instantaneous change in air temperature can cause abrupt thermoregulation responses. Thermal sensation vote (TSV) and thermal comfort vote (TCV) assessments as a consequence of moving through spaces with distinct thermal conditions were conducted in an existing single-story office in a hot-humid microclimate, maintained at an air temperature 24 °C (± 0.5), relative humidity 51% (± 7), air velocity 0.5 m/s (± 0.5), and mean radiant temperature (MRT) 26.6 °C (± 1.2). The measured office is connected to a veranda that showed the following semi-outdoor temperatures: air temperature 35 °C (± 2.1), relative humidity 43% (± 7), air velocity 0.4 m/s (± 0.4), and MRT 36.4 °C (± 2.9). Subjective assessments from 36 college-aged participants consisting of thermal sensations, preferences and comfort votes were correlated against a steady state predicted mean vote (PMV) model. Local skin temperatures on the forehead and dorsal left hand were included to observe physiological responses due to thermal transition. TSV for veranda-office transition showed that no significant means difference with TSV office-veranda transition were found. However, TCV collected from warm-neutral (-0.24, ± 1.2) and neutral-warm (-0.72, ± 1.3) conditions revealed statistically significant mean differences (p < 0.05). Sensory and affective responses as a consequence of thermal transition after travel from warm-neutral-warm conditions did not replicate the hysteresis effects of brief, slightly cool, thermal sensations found in previous laboratory experiments. These findings also indicate that PMV is an acceptable alternative to predict thermal sensation immediately after a down-step thermal transition (≤ 1 min exposure duration) for people living in a hot-humid climate country.

Matched MeSH terms: Air Conditioning/adverse effects*; Air Conditioning/methods; Air Movements
Impact of Climate Change on Air Quality and Public Health in Urban Areas

Hassan NA, Hashim Z, Hashim JH

Asia Pac J Public Health, 2016 Mar;28(2 Suppl):38S-48S.
PMID: 26141092 DOI: 10.1177/1010539515592951

This review discusses how climate undergo changes and the effect of climate change on air quality as well as public health. It also covers the inter relationship between climate and air quality. The air quality discussed here are in relation to the 5 criteria pollutants; ozone (O3), carbon dioxide (CO2), nitrogen dioxide (NO2), sulfur dioxide (SO2), and particulate matter (PM). Urban air pollution is the main concern due to higher anthropogenic activities in urban areas. The implications on health are also discussed. Mitigating measures are presented with the final conclusion.

Matched MeSH terms: Air Pollutants/analysis*; Air Pollution/adverse effects*

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