• 설비공학논문집
• /
• 제18권3호
• /
• pp.262-269
• /
• 2006

Formaldehyde and total volatile organic compounds (TVOC) from building materials have been known as main causes of IAQ problem in Newly-Constructed Multi-Family Houses. Because Multi-Family Houses are built in large quantities in a similar manner, inappropriate selection of building materials and method will detrimental affect IAQ. This research aims to identify major causes of Indoor Air Pollutants in Multi-Family Houses, by constructing Mock-Up & One-Room House. As a result, self leveling concrete, door, and furniture construction is a major cause of indoor formaldehyde increase, and tile bond is TVOC, and urethane water proof is Etylbenzene, and Xylene.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2006년도 하계학술발표대회 논문집
• /
• pp.283-288
• /
• 2006

Indoor Air Quality Guideline of Kindergarten in korea didn't consider the vulnerable properties of children to indoor air pollutants. For this reason, Suggestion for the IAQ guideline of formaldehyde and minimum ventilation rate was made in this study. Suggested IAQ guidelines for formaldehyde in the respect of children's vulnerable immune system is $30{\mu}g/m^3$ and $50{\mu}g/m^3$, and for the ventilation rate 11.9 ACH, 5.8 ACH, respectively. This value is based only formaldehyde and CO2 concentrations in child-care room of Kindergarten and needed to be verified by further investigations and studies. However it is discovered that lower formaldehyde concentration can do mal-effects to children's health by literature review.

• Journal of the Korean Wood Science and Technology
• /
• 제50권2호
• /
• pp.104-112
• /
• 2022

Indoor air quality is a very important environmental factor in modern society. However, air pollutants generated from various interior construction materials significantly affect the human body, including formaldehyde (HCHO) and volatile organic compounds that threaten public health by deteriorating indoor air quality. Effective in removing these harmful substances are porous materials, such as woodceramics. In this study, charcoal, a porous material, was added to rice husk, an agricultural by-product, and sawdust generated during the sawing process to prepare boards and ceramics at different mixing ratios, and the HCHO deodorization performance and far-infrared emission characteristics were measured. As the mixing ratio of charcoal increased, the deodorization rate of the boards and ceramics tended to increase. Overall, the deodorization rate was measured to be 80% to 90%, indicating that the boards and ceramics prepared with charcoal are suitable to be used for the purpose of deodorization. The effect of the material mixing ratio on far-infrared emissivity and emission power was insignificant.

• 한국세라믹학회지
• /
• 제53권2호
• /
• pp.134-138
• /
• 2016

Porous $Co_3O_4$ spheres with bimodal pore distribution (size: 2-3 nm and ~ 30 nm) were prepared by ultrasonic spray pyrolysis of aqueous droplets containing Co-acetate and polyethylene glycol (PEG), while dense $Co_3O_4$ secondary particles with monomodal pore distribution (size: 2-3 nm) were prepared from the spray solution without PEG. The formation of mesopores (~ 30 nm) was attributed to the decomposition of PEG. The responses of a porous $Co_3O_4$ sensor to various indoor air pollutants such as 5 ppm $C_2H_5OH$, xylene, toluene, benzene, and HCHO at $200^{\circ}C$ were found to be significantly higher than those of a commercial sensor using $Co_3O_4$ and dense $Co_3O_4$ secondary particles. Enhanced gas response of porous $Co_3O_4$ sensor was attributed to high surface area and the effective diffusion of analyte gas through mesopores (~ 30 nm). Highly sensitive porous $Co_3O_4$ sensor can be used to monitor various indoor air pollutants.

• KIEAE Journal
• /
• 제17권5호
• /
• pp.33-41
• /
• 2017

Purpose: Indoor air quality in residential buildings needs to be evaluated over the long term. In previous research, there has been an attempt to perform the health risk assessment of pollutants by using numerical models as a method of long-term evaluation. However, the numerical model of this precedent study has limitations that do not reflect the actual concentration distribution. Therefore, this study introduces the CRPS index, constructs a numerical model that can reflect the concentration distribution, and then presents a more accurate health risk assessment method using it. At this time, the pollutants are toluene, which is a typical material released from building materials. Method: CRPS index was applied to existing numerical model to reflect concentration distribution. This was used to calculate concentrations at adult breathing area and to use them for exposure assessment in a health risk assessment. After that, we entered adult data and conducted a health risk assessment of toluene. Results: The non-carcinogenic risk of toluene was calculated to be 0.0060. This is 5% smaller than the existing numerical model, meaning that it is more accurate to predict the pollutant risks. This value is also lower than the US EPA reference value of 1. Therefore, under the conditions of this study, long-term exposure of adults to toluene has no impact on health.

• 설비공학논문집
• /
• 제15권9호
• /
• pp.733-737
• /
• 2003

The purpose of this study is to analyze the particle removal characteristics of a commercial air cleaner based on the electrostatic precipitator. The air cleaner consists of a positive corona precharger to precharge particles and a collector to remove the charged particles. The test for particle removal efficiency is conducted with tobacco smoke particles of 1.27${\mu}{\textrm}{m}$ in mass median diameter. The result of one-pass filtration test shows that the filtration efficiency is more than 90% for the particles larger than 2.5 Um, while the efficiency for the particles of 0.5～1.0${\mu}{\textrm}{m}$ in case of 4.18 CMM is 70%. For the test room of 5,800${\times}$3,400${\times}$2,600㎣, the concentration of tobacco smoke particles decreases up to 30% of initial values within 30 minutes due to natural reduction and up to 90% of initial values within 30 minutes with the air cleaner operation.

• 한국산업보건학회지
• /
• 제20권2호
• /
• pp.102-110
• /
• 2010

Personal exposure relies on characteristics of time activity patterns of the population of concern as human activities impact the timing, location, and level of personal exposure. The information about time spent in microenvironments plays a critical role for personal exposure to air pollutants. It is useful to determine the precise times of the day that the subjects are in certain locations or engaging in specific activities because exposure to some air pollutants can depend on temporal trends. This study investigated time activity pattern for workers of Korean population over 19 years old with 8,778 workers in weekday. The residential indoor times were 12 hours. Time activity was different by gender and the mean times stayed at home in weekday were 12.9 hours in female and 11.42 hours in male, respectively. The major factors on residential indoor time and workplace time were age, monthly income, occupation and industry type, work position, education, and gender. Considering shorter than those in other countries, Korean workers spent less time at home after the working hours. Determinants of time activity pattern need to be taken into account in exposure assessment, epidemiological analyses, exposure simulations, as well as in the development of preventive strategies. Since there are substantial difference of Korean worker activity pattern, this information can be critical for exposure assessment in Korea.

• 한국대기환경학회지
• /
• 제28권4호
• /
• pp.365-373
• /
• 2012

This study compared indoor air quality of homes in which elementary school children with and without (case and control) allergic rhinitis live in the Ulsan metropolitan region (UMR). A total of 58 homes (case and control: 29, respectively; children aged 7 to 12 years) was selected for indoor air quality measurements. The concentrations of all general indoor air pollutants, except $PM_{2.5}$, in the case group were much higher than those in the control group. In particular, the average concentrations of $O_3$ and $NO_2$ in the case group were statistically significantly (p<0.05) higher than those in the control group. Average concentrations of $CO_2$ in the case and control groups and $NO_2$ in the case group exceeded the standard level. Some components of aldehydes and ketones and VOCs indicated large difference of average concentrations between two groups, but there were no statistically significant differences.

• 토지주택연구
• /
• 제6권4호
• /
• pp.231-237
• /
• 2015

본 연구는 다변화 되는 건설환경에서 모듈러 주택에 대한 관심이 높아지고 있어 모듈러 목업 주택을 대상으로 신축시 실내공기질 현황을 측정하였다. 붙박이 가구가 미설치된 세대(101호)와 붙박이 가구가 설치된 세대(102호), 2세대를 대상으로 시간경과에 따라 3차 측정을 실시하였다. 1차는 마감 및 붙박이 가구 설치 직후 측정하였으며 2차는 베이크아웃 실시 이후, 3차는 약 2.5개월(77일) 이후 측정하였다. 측정결과 1차 측정시 붙박이 가구 설치세대가 오염물질 방출농도가 높았으나 톨루엔의 경우를 제외하고 모두 권고기준 이하로 나타났다. 3차 측정시에는 톨루엔과 스티렌을 제외하고 두세대가 유사한 방출량으로 나타났으며 두세대 모두 미미한 수준으로 방출량이 낮아졌다. 이는 측정세대 모듈이 적어($14.7m^2$) 베이크아웃 및 환기에 의한 영향이 크게 나타난 것으로 판단되며 이를 통해 오염물질이 외부로 방출되어 저감된 것으로 판단된다. 일반 공동주택의 입주시점을 고려한다면 모듈러 주택의 경우도 모두 실내공기질 권고기준 이하로 나타날 것으로 판단되며, 가구에 의한 영향은 톨루엔이 가장 큰 영향을 받는 것으로 나타났다. 향후에는 모듈조합을 통해 중형 이상 규모 모듈러 주택에 있어서 가구설치 여부에 따른 상관관계를 살펴 볼 필요성이 있을 것으로 판단된다.

• 한국대기환경학회지
• /
• 제3권2호
• /
• pp.46-52
• /
• 1987

There are many factors such as airtighteness and high density of merchandises or passengers that contaminate indoor air in underground commercial floor. So it is very important to know air quality and quantity of contamination in underground market increasing in number lately. It was from these viewpoints that gaseous pollutants, dusts and mutagenicity of organic compounds extracted from dusts in an underground market were investigatd. Organic ompounds (tar) were extracted by Soxhlet extractor with benzene as a solvent. Mutagenicities of these extracts were evaluated by the preincubation method using Salmonella typhimurium TA 100 and TA 98 strains with and without S9mix. The results obtained were as follows: It seemed to be under the influence of outdoor air that the concentrations of $CO, CO_2, NO, NO_2$ and dusts were higher in winter than summer. The concentration of $CO_2$ was higher in indoor than outdoor, but the concentration of NOx was similar in both sampling areas. Metal contents in dusts attached to the ventilation ducts were as follows showing in order of high concentration : Fe (9000-22000ppm), Zn(1200-2300ppm) and Pb (280-590ppm). The contents of tar were 6-33% of dusts, and higher than those from dusts collected by high volume air sampler. The extracts from dusts attached to the inlet duct exhibited lower mutagenicity than those from dusts attached to the outlet duct. This finding seemed to suggest that mutagenic substances were in creasing in underground. There was no seasonal difference of mutagenicity toward TA 98. Toward TA 100 in the presence of S9mix, the mutagenicity was about 3 fold higher in winter than summer. The mutagenicities of tar extracted from dusts collected by high volume air sampler were different from those attached to the ventilation ducts. The former showed 2-3 fold higher mutagenicity than the latter toward TA 100. However no difference showed between the former and the latter toward TA 98 in the absence of S9mix, but the former was 4-5 fold higher than the latter in the presence of S9mix.