scholarly journals Indoor Air Quality Assessment Based on Human Physiology - Part 2. Limits

10.14311/494 ◽  
2003 ◽  
Vol 43 (6) ◽  
Author(s):  
M. V. Jokl

In order to evaluate indoor air quality in practice it is necessary to establish limits, or more exactly, tolerable ranges for unadapted and adapted persons. The optimal value overwhelmingly corresponds to PD 20 %. A better value of PD 10 % could be prescribed for asthmatics and for persons with increased requirements, i.e. those allergic to the environment and operators in airport control towers and atomic power stations. A worse value PD 30 % could be accepted as an admissible value. These values differ for unadapted and adapted persons (as introduced by BSR/ASHRAE 62-1989 R). The long-term tolerable value is the end of SBS range (for CO2 it is based on USSR space research, for TVOC on Molhave). The short-term tolerable value is the beginning of the toxic range (for CO2 it is taken from British Guidance Note EH 40/90; for TVOC from Molhave).

2020 ◽  
pp. 1420326X2092474
Author(s):  
Tingxuan Deng ◽  
Xiong Shen ◽  
Xiaojie Cheng ◽  
Junjie Liu

Indoor air quality (IAQ) is a key factor that could affect the indoor environment and people's health. In this study, we report a comprehensive study on IAQ in 30 dwellings in the temperate zone in China. Thirty naturally ventilated dwellings were selected in the urban area of Kunming, which is the largest city in temperate zone in China. In four seasons, short-term measurement of formaldehyde and benzene, toluene, xylenes-volatile organic compounds and air infiltration rate were conducted in these dwellings. A long-term 1-year monitoring of temperature, relative humidity, fine particulate matter (PM2.5), carbon dioxide (CO2), window-opening behaviour and night-time air change rate (ACR) were conducted in 13 of these dwellings by remote sensors. Short-term measurements showed the mean formaldehyde concentration in summer (100.76 μg/m3), benzene concentration in winter (8.46 µg/m3), PM2.5 concentration (80.4 µg/m3) in spring of 2017 exceeded the Chinese standard, the US Office of Environmental Health Hazard Assessment value and the World Health Organization guidelines. The night-time ACR was the highest in summer (2.1 h−1) and the lowest in winter (1.6 h−1) in bedrooms of 13 long-term monitored dwellings due to seasonal time variation in window opening in bedrooms, which was mainly driven by CO2 concentration, indoor temperature and outdoor PM10 concentration.


10.14311/492 ◽  
2003 ◽  
Vol 43 (6) ◽  
Author(s):  
M. V. Jokl

Human physiology research makes evident that the Weber-Fechner law applies not only to noise perception but also to the perception of other environmental components. Based on this fact, new decibel units for dor component representing indoor air quality in majority locations have been proposed: decicarbdiox dCd (for carbon dioxide CO2) and decitvoc dTv (for total volatile organic compound TVOC). Equations of these new units have been proved by application of a) experimental relationships between odor intensity (representing odor perception by the human body) and odor concentrations of CO2 and TVOC, b) individually  measured CO2 and TVOC levels (concentrations) – from these new decibel units can be calculated and their values compared with decibel units of noise measured in the same locations. The undoubted benefit of using the decibel scale is that it gives much better approximation to human perception of odor intensity compared to the CO2 and TVOC concentration scales.


10.14311/496 ◽  
2003 ◽  
Vol 43 (6) ◽  
Author(s):  
M. V. Jokl

The proposed evaluation system allows something quite new: a) the assessment of the effect of each environmental component (constituent) on the total environment level, b) accurate estimation of air volume for various locations, human occupations and sources of harmful gases. Additional benefits are listed at the conclusion of this part.


Author(s):  
Kamarul Aini Mohd Sari ◽  
Khaleda Farhah Almar Mastaza ◽  
Mohammad Ashraf Abdul Rahman ◽  
Mohd Kamaruzaman Musa ◽  
Mariah Awang ◽  
...  

2019 ◽  
Vol 14 (4) ◽  
pp. 93-109
Author(s):  
Abd Halid Abdullah ◽  
Yee Yong Lee ◽  
Eeydzah Aminudin ◽  
Yeong Huei Lee

The indoor air quality (IAQ) in office buildings should be assessed for public health concerns as it relates to work performance and productivity. Therefore, this paper aims to assess the IAQ in a university office building. From this investigation, the level of contaminated indoor air is examined, the significant causes and contributing factors of contaminated indoor air are determined and a recommendation to improve the existing condition has been proposed. The physical parameters measured include air temperature, air velocity, relative humidity, and concentrations of carbon dioxide (CO2), carbon monoxide (CO), sulphur dioxide (SO2), and also air particles. It was found that the number of air particles of 0.5 μm in diameter is about 197,748 particles/m3, while air particles of 5.0 μm in diameter is around 534 particles/m3. The collected data were then compared with a questionnaire and IAQ standards. In conclusion, the indoor air quality within the multi-storey central office building of Universiti Tun Hussein Onn Malaysia (UTHM) is acceptable and suitable for occupation even though there were countable symptoms of Sick Building Syndrome (SBS) among its occupants.


2018 ◽  
Vol 33 (1) ◽  
pp. 63-76 ◽  
Author(s):  
Harriet Whiley ◽  
Sharyn Gaskin ◽  
Tiffany Schroder ◽  
Kirstin Ross

AbstractConcerns regarding indoor air quality, particularly the presence of fungi and moulds, are increasing. The potential for essential oils to reduce, control or remove fungi, is gaining interest as they are seen as a “natural” alternative to synthetic chemical fungicides. This review examines published research on essential oils as a method of fungal control in indoor environments. It was difficult to compare the relative performances of essential oils due to differences in research methods and reporting languages. In addition, there are limited studies that scale up laboratory results and assess the efficacy of essential oils within building environments. However, generally, there appears to be some evidence to support the essential oils clove oil, tea tree oil, oregano, thyme and lemon as potential antifungal agents. Essential oils from heartwood, marjoram, cinnamon, lemon basil, caraway, bay tree, fir, peppermint, pine, cedar leaf and manuka were identified in at least one study as having antifungal potential. Future studies should focus on comparing the effectiveness of these essential oils against a large number of fungal isolates from indoor environments. Studies will then need to focus on translating these results into realistic application methods, in actual buildings, and assess the potential for long-term antifungal persistence.


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