scholarly journals EFFECTS OF HOOVERING ACTIVITIES ON BIOLOGICAL CONTAMINANTS AND PARTICULATE MATTER LEVELS IN MAIN PRAYER HALLS OF MALAYSIAN MOSQUES

2019 ◽  
Vol 14 (1) ◽  
pp. 134-142
Author(s):  
Nor Azam Ramli ◽  
Nur Baitul Izati Rasli ◽  
Mohd Rodzi Ismail ◽  
Syabiha Shith ◽  
Noor Faizah Fitri Md Yusof ◽  
...  
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Fungal Growth ◽  
Fungal Species ◽  
Bacterial Counts ◽  
Code Of Practice ◽  
Bacillus Spp ◽  
Ventilation Strategies ◽  
Bacteria And Fungi

In Malaysia, carpets are commonly used as finishing flooring material in the main prayer hall of mosques. In cleaning carpets, hoovering has been the most popular method, but it directly triggers the uplifting of dust that may contain bacteria and fungi. Hoovering activities and ventilation strategies (air conditioning split units (ACSUs) or by active ventilation (non-ACSUs)) can affect the prevalence of bacterial and fungal growth. This study aimed to establish the total bacterial counts, total fungal counts and also PM10 concentrations under different ventilation strategies (ACSUs and non-ACSUs) in the main prayer halls of mosques. Identification of bacterial and fungal species also took place in this study. Sampling was performed in 25 mosque buildings (17 ACSUs and 8 non-ACSUs) with carpeted flooring on Zohor-Asar and Friday-Asar prayer sessions at Pulau Pinang, Malaysia. Results revealed that the total bacterial counts, total fungal counts and mean PM10 concentrations were higher in mosques with ACSUs than in mosques with non-ACSUs at concentrations ranging from 166cfu/m3 to 660 cfu/m3, from 118 cfu/m3 to 660 cfu/m3 and from 11.15 ± 9.32 µg/m3 to 49.30 ± 13.13 µg/m3, respectively. The total bacterial counts exceeded the acceptable guideline limit by the Industrial Code of Practice on Indoor Air Quality (ICOP), but the total fungal counts and PM10 concentrations did not. In some mosques, the total bacterial and fungal counts did not decrease even after hoovering activities were completed. The dominant types of bacteria found in the mosque buildings were Staphylococcus spp., Bacillus spp. and Micrococci spp., whilst the dominant fungal species was Aspergillus niger. Although the findings were not alarming, care should be taken by mosques authorities especially while and after hoovering, to ensure that, the indoor air quality in mosques are being maintained within the permissible limit to protect worshippers from being exposed to bacterial and fungal.

Assessment of the indoor air quality based on airborne bacteria and fungi measurements in a public school of Istanbul

2020 ◽  
Vol 13 (24) ◽  
Author(s):  
Nuket Sivri ◽  
Ahmet Ozgur Dogru ◽  
Arzu Funda Bagcigil ◽  
Kemal Metiner ◽  
Dursun Zafer Seker
Keyword(s):  
Air Quality ◽  
Public School ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Airborne Bacteria ◽  
Bacteria And Fungi

scholarly journals Window operation behaviour and indoor air quality during lockdown: A monitoring-based simulation-assisted study in London

2021 ◽  
pp. 014362442110177
Author(s):  
Farhang Tahmasebi ◽  
Yan Wang ◽  
Elizabeth Cooper ◽  
Daniel Godoy Shimizu ◽  
Samuel Stamp ◽  
...  
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Energy Demand ◽  
Natural Ventilation ◽  
Probabilistic Models ◽  
Performance Model ◽  
Outdoor Environment ◽  
Ventilation Strategies ◽  
The Impact

The Covid-19 outbreak has resulted in new patterns of home occupancy, the implications of which for indoor air quality (IAQ) and energy use are not well-known. In this context, the present study investigates 8 flats in London to uncover if during a lockdown, (a) IAQ in the monitored flats deteriorated, (b) the patterns of window operation by occupants changed, and (c) more effective ventilation patterns could enhance IAQ without significant increases in heating energy demand. To this end, one-year’s worth of monitored data on indoor and outdoor environment along with occupant use of windows has been used to analyse the impact of lockdown on IAQ and infer probabilistic models of window operation behaviour. Moreover, using on-site CO2 data, monitored occupancy and operation of windows, the team has calibrated a thermal performance model of one of the flats to investigate the implications of alternative ventilation strategies. The results suggest that despite the extended occupancy during lockdown, occupants relied less on natural ventilation, which led to an increase of median CO2 concentration by up to 300 ppm. However, simple natural ventilation patterns or use of mechanical ventilation with heat recovery proves to be very effective to maintain acceptable IAQ. Practical application: This study provides evidence on the deterioration of indoor air quality resulting from homeworking during imposed lockdowns. It also tests and recommends specific ventilation strategies to maintain acceptable indoor air quality at home despite the extended occupancy hours.

Assessing ventilation strategies in a school with observed indoor air problems

Facilities ◽  
2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ulrika Uotila ◽  
Arto Saari ◽  
Juha-Matti Kalevi Junnonen ◽  
Lari Eskola
Keyword(s):  
Decision Making ◽  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Final Decision ◽  
Target Number ◽  
Content Type ◽  
Existing Building ◽  
Ventilation Strategies

Purpose Poor indoor air quality in schools is a worldwide challenge that poses health risks to pupils and teachers. A possible response to this problem is to modify ventilation. Therefore, the purpose of this paper is to pilot a process of generating alternatives for ventilation redesign, in an early project phase, for a school to be refurbished. Here, severe problems in indoor air quality have been found in the school. Design/methodology/approach Ventilation redesign is investigated in a case study of a school, in which four alternative ventilation strategies are generated and evaluated. The analysis is mainly based on the data gathered from project meetings, site visits and the documents provided by ventilation and condition assessment consultants. Findings Four potential strategies to redesign ventilation in the case school are provided for decision-making in refurbishment in the early project phase. Moreover, the research presents several features to be considered when planning the ventilation strategy of an existing school, including the risk of alterations in air pressure through structures; the target number of pupils in classrooms; implementing and operating costs; and the size of the space that ventilation equipment requires. Research limitations/implications As this study focusses on the early project phase, it provides viewpoints to assist decision-making, but the final decision requires still more accurate calculations and simulations. Originality/value This study demonstrates the decision-making process of ventilation redesign of a school with indoor air problems and provides a set of features to be considered. Hence, it may be beneficial for building owners and municipal authorities who are engaged in planning a refurbishment of an existing building.

Monitoring of Selected Indoor Air Quality Parameters and Cooling Energy Usage in Hotel Restaurant Malaysia

2014 ◽  
Vol 564 ◽  
pp. 250-255
Author(s):  
M.M. Syafiq Syazwan ◽  
Mohammad Zainal M. Yusof ◽  
C.K. Chang ◽  
M.D. Amir Abdullah
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Quality Parameters ◽  
Internal Source ◽  
Energy Usage ◽  
Code Of Practice ◽  
Loads Analysis ◽  
Air Ventilation ◽  
Psychrometric Chart

Sensible (temperature) and latent (moisture) loads are the common load an air-conditioning (AC) system need to handle. Both loads are generated from conditioned space, internal source and outdoor air ventilation. This study is to monitor the indoor air quality IAQ in hotel restaurant and the results are compared with Malaysian standard MS1525 and Industry Code of Practice (COP) on IAQ 2010, Department of Safety and Health (DOSH) Malaysia. The AC system performance was also monitored to identify the actual cooling energy usage base on standard operations. Psychrometric chart was used to analyse the actual cooling energy required and identified the latent and sensible loads significantly. The result of the study shows the mean air temperature, relative humidity (RH), carbon dioxide (CO) and carbon monoxide (CO2) levels were within range as stipulated by standard and code of practice. Heat loads analysis on a psychrometric chart showed the total cooling energy as 296.2 kW; of which 196.3 kW was contributed to primary air unit (PAU) and 99.9 kW to air handling unit (AHU) respectively. The primary contribution for sensible and latent loads and recommendation of potential energy saving also been discussed to meet energy efficient in AC system while maintaining good indoor air quality in the restaurant.

scholarly journals HVAC Ventilation Strategies: The Contribution for Thermal Comfort, Energy Efficiency, and Indoor Air Quality

2007 ◽  
Vol 2 (2) ◽  
pp. 131-150 ◽  
Author(s):  
Jatuwat Varodompun ◽  
Mojtaba Navvab
Keyword(s):  
Air Quality ◽  
Thermal Comfort ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Cfd Simulation ◽  
Indoor Environmental Quality ◽  
Ventilation Strategy ◽  
Jet Ventilation ◽  
Advantages And Disadvantages ◽  
Ventilation Strategies

In Heating Ventilating and Air Conditioning (HVAC) systems, ventilation strategies impact building energy consumption, occupants' thermal comfort and Indoor Air Quality (IAQ). Ventilation strategies such as Mixing Jet Ventilation (MJV), Displacement Ventilation (DV), and Impinging Jet Ventilation (IJV) are operated on the different principals. MJV relies on dilution, while DV and IJV rely on both dilution and stratification. Due to climatic variation, ventilation strategies must be operated under different cooling and heating load scenarios. Typically, each ventilation strategy controls the indoor environment through a single adequate flow rate with suitable supply parameters such as temperature, pollutant concentration, vapor, velocity, etc. Hence, the indoor thermal and IAQ condition are independently impacted. A room with excellent thermal condition is possible to have poor IAQ. Given this limitation, vast air flow variables, and occupants' activities, the performances evaluation of these strategies are complicated. In this study, three ventilation strategies, MJV, DV, and IJV are thoroughly investigated. The Computational Fluid Dynamics (CFD) simulation was mainly utilized to handle the complexity of this study. The parametric studies of 48 CFD simulations are presented. Referring to ASHRAE RP-1133, the experimental data from a specially built HVAC-IEQ laboratory was used to validate the CFD data. The research results indicate both advantages and disadvantages in all three strategies. In addition, there is no single strategy that can perform excellently in all indexes. Using the well-known index called ventilation effectiveness (VEF), DV performs outstandingly. However, under a newly proposed index called ventilation performances, DV fails because the stratification discomfort exceeds 36% of room area. MJV suffers from low VEF and excessive draft. However, the IAQ of MJV is not as poor as expected. IJV can be an alternative especially for space where sleeping and sitting activities dominate. IJV can conserve HVAC energy, while maintaining good IAQ. Compared to DV, although VEF is lower, stratification discomfort is minimized to 24%–12% (depending on supply velocity). Overall, this study demonstrates that ventilation strategies are the key to enhance IAQ. Therefore, the utilization of an appropriate ventilation strategy might increase, Leadership in Energy and Environmental Design (LEED) score, particularly for Indoor Environmental Quality, Innovation and Design Process, and Energy and Atmospheric categories.

scholarly journals Assessment of Indoor Microbiological Air Contamination in Research Facility at University of Malaysia

2020 ◽  
Author(s):  
Sytty Mazian Mazlan ◽  
Ainon Hamzah ◽  
Wan Syaidatul Aqma Wan Mohd Noor ◽  
Azlan Abas
Keyword(s):  
Air Quality ◽  
Relative Humidity ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Micrococcus Luteus ◽  
Ventilation System ◽  
Bacillus Sphaericus ◽  
Fungal Species ◽  
Morphological Examination ◽  
Air Contamination

Abstract Indoor air quality is a concept that applies to the nature of the environment in and around buildings and facilities in which it contributes to the safety and security of those in the house. The aim of this study was to identify bacterial and fungal species present in the room, determine indoor air quality and investigate consumer views on indoor air quality in the Biology Building, Faculty of Sciences and Technology, National University of Malaysia. This study was conducted at the Biology Building at 8 selected sampling sites. Microbes were sampled using nutrient agar (bacteria) and potato dextrose agar (fungus). All samples of microbes were classified using two approaches; i) morphological examination and ii) biochemical reaction experiments. CO2, temperature and relative humidity are registered using the Direct Sense Monitoring Kit. A survey on customer satisfaction with indoor air quality in the building was carried out and evaluated in order to collect empirical details. This study found that the presence of Bacillus cereus, Bacillus laterosporus, Bacillus sphaericus, Micrococcus luteus, Staphylococcus aureus, Staphylococcus epidermis, Enterobacter cloacae, Pseudomonas fluarescens, Pseudomonas stuzeri and Aeromonas hydrophila bacterial. The fungi species are Aspergillus niger, Aspergillus nidulans, Penicillium digitatum and Fusarium dimerum. The result also shows that the carbon dioxide, temperature and relative humidity concentrations for most sampling stations comply with the DOSH standards. Moreover, almost all participants reported that their level of health and comfort while in the building is good, while the ventilation system of the building is at a comfortable level. Whereas, the degree of knowledge for most respondents on the value of indoor air quality is high. Two of the recommendations included in this study to enhance indoor air quality are to insure that the air conditioning device is correctly controlled and to raise understanding of the value of indoor air quality among staff and students in the Biology Building.

scholarly journals The Determination of Indoor Air Quality and Thermal Comfort with Different Space and Ventilation in the Teracce and Bungalow Houses

2021 ◽  
Vol 16 (3) ◽  
pp. 774-793
Author(s):  
Nur Baitul Izati Rasli ◽  
Nor Azam Ramli ◽  
Mohd Rodzi Ismail
Keyword(s):  
Air Quality ◽  
Thermal Comfort ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Natural Ventilation ◽  
Ventilation System ◽  
Physical Parameters ◽  
Air Contaminants ◽  
Code Of Practice ◽  
Air Movement

This study observed the influence of different ventilation, indoor and outdoor activities (i.e., cooking, praying, sweeping, gathering, and exhaust from motorcycle) between a bungalow house (i.e., stack and cross ventilation applications) and a terrace house (i.e., one-sided ventilation application). We appraised the indoor air quality (IAQ) and thermal comfort. We monitored the indoor air contaminants (i.e., TVOC, CO, CH2O, PM10, O3, and CO2) and specific physical parameters (i.e., T, RH, and AS) for four days in the morning (i.e., 6.00 a.m. – 9.00 a.m.), morning-evening (i.e., 11.00 a.m. – 2.00 p.m.), and evening-night (i.e., 5.00 p.m. – 8.00 p.m.) sessions. The results found that cooking activities are the major activities that contributed to the increase of the TVOC, CO, PM10, O3, and CO2 concentrations in the bungalow and terrace houses. However, IAQ exceeded the Industry Code of Practice on IAQ (ICOP) limit in the terrace house. The bungalow house applies stack and cross ventilation, double area, and a long pathway of indoor air contaminants movements. Besides that, the results indicated that cooking activities worsen the ventilation system because CO2 exceeded the ICOP limit on Day 2 at 74.1 % (evening-night session) and Day 3 at 13.2 % (morning session), 11% (morning-evening session), and 50.1 % (evening-night session). Moreover, the combination of mechanical (i.e., opened all fans) and natural ventilation (i.e., opened all doors, windows, and fans) is the best application in the house without a cooking ventilator with lower indoor air movement. Furthermore, the temperatures exceeding the ICOP limit of 23-26 °C for both bungalow and terrace houses could be lower indoor air movement, which is less than the ICOP limit of 0.15-0.5 m/s and high outdoor air temperature. Therefore, it is prudent to have an efficient ventilation system for acceptable indoor air quality and thermal comfort in the family house.

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