In this paper, we conducted a survey to reveal the general perception of parents toward outdoor air quality, particulate matter (PM), and indoor air quality (IAQ) at schools where their children attend. A total of 1,030 parents participated in this survey, where the age of their children ranged between 7 years to over 19 years of age. Each participant was either a member of a non-governmental organization (NGO) with a keen interest in air quality or an ordinary public panel member with less interest. The result of the survey indicated that the participants had a negative perception of air quality, and parents believed that the outdoor and indoor air is extremely polluted. The participants pointed out that they believe that the main reason for the pollution is due to particulate matter (PM) and school classrooms are the location where their children are exposed to PM the most. Based on our study, the majority of the participants prefer a mechanical ventilation system to reduce indoor air pollutants in schools. Our study should be referred to by school officials in order to maintain IAQ and as a way of addressing the concerns of parents who want to protect their children’s health.
The objective of this study was to investigate the effect of shoe dust on the indoor environment, and the effectiveness of shoe dust control on indoor air quality. Test dust was resuspended to reach a mass concentration of particles (2.5-10 μm size) more than 3 times compared to background level, and 1.5 times for particles less than 1 μm in size. The shoes, which were used for actual walking purposes in the outdoor environment, increased indoor PM10 concentration by 118±9%. The removal of shoe dust by water washing and mechanical suction brought about an improvement of indoor air quality. In particular, in circumstances where 27 people walked for one hour into the indoor environment, the mechanical suction of shoe dust decreased PM10 concentration by about 17% (based on the mass balance analysis).
The purpose of this study was to evaluate the concentration of airborne particulate matter and heavy metals in the houses of the respiratory tract disease patients and a control group of residents in the city of Gwangyang. The particulate matter was measured using a mini-volume air sampler and then weighed three times using a micro balance to calculate the weighted average value. The heavy metals in the particulate matter were extracted using a hot plate and analyzed using an inductively coupled plasma/mass spectrometer. The average concentration of particulate matter in the outdoor air (34.478 μm/m3) was higher than that in the indoor air (16.794 μm/m3), showing a statistically significant difference (p<0.001). The average concentration of copper, manganese and chromium in the indoor and outdoor air were higher in the houses of those in the study group than those of the control group. In addition, there was a generally high correlation between particulate matter in the outdoor air and heavy metals in the indoor and outdoor air concentration (p<0.05).
We measured VOCs and NO2 in the indoor and outdoor air at 125 houses in Jeollanam-do and Gyeongsangnamdo, from March 2007 to January 2008. The concentration of benzene measured in the Gwangyang survey group was higher than in Yeosu and Hadong, and showed a statistically significant difference from Yeosu (p<0.05). The concentration of toluene in outdoor air was highest in the Gwangyang survey group. The concentration of NO2 measured in the Yeosu survey group was higher than in Gwangyang and Hadong, and showed a statistically significant difference from Hadong (p<0.01). According to the results of a correlation analysis, VOCs (benzene, toluene, xylene, ethylbenzene) exposure of individuals showed a significant correlation with the residential indoor air (p<0.01). Also, VOCs of residential indoor and outdoor air showed a significant correlation (p<0.01). The concentration of NO2 exposure of individuals measured in the Yeosu comparison group showed a high correlation with the residential indoor air.
Indoor air quality can be affected by indoor sources, ventilation, decay and outdoor levels. Although technologies exist to measure these factors, direct measurements are often difficult. Toluene and nitrogen dioxide (NO2) concentrations of residential indoor and outdoor were simultaneously measured and compared in 16 houses, using passive samplers during every 3 days for 60 days. Concentrations of toluene and NO2 were analyzed by gas chromatography and spectrophotometer, respectively. Using a mass balance model, penetration factor (ventilation rate divided by sum of ventilation rate and deposition constant) and source generation factor (source generation rate divided by sum of ventilation rate and deposition constant) were calculated by multiple indoor and outdoor measurements. The mean contributions of toluene of indoor and outdoor sources on residential indoor air quality were estimated to be 31.01% and 67.00%, respectively. On the other hand, mean contributions of NO2 were 58.93% and 41.06%, respectively. These results could be explained that contributions of indoor and outdoor air pollutants sources are different to residential indoor air concentrations. In conclusion, contributions of outdoor air and indoor sources affecting indoor air quality were effectively characterized using multiple indoor and outdoor measurements.
Exposure to nitrogen dioxide (NO2) can produce adverse health effects. Various indoor and outdoor combustion sources make NO2 the most ubiquitous pollutant in the indoor environment. Indoor air quality can be affected by indoor sources, ventilation, decay and outdoor levels. Although technologies exist to measure these factors, direct measurements are often difficult. In the present paper, we used a mass balance model and regression analysis, penetration factor (ventilation rate divided by the sum of ventilation rate and deposition constant) and source strength factor (source strength divided by the sum of ventilation rate and deposition constant) were calculated using multiple indoor and outdoor measurements with 10 houses. Subsequently, mean contributions of indoor and outdoor sources were 28.86% and 81.09%, respectively, suggesting that both indoor and outdoor sources had contributions to indoor concentrations of NO2.
The work of hairdressers includes washing, coloring, bleaching, permanent waving, conditioning, and cutting scalp hair. Hairdressers are subjected to a number of physical and toxicological hazards. The toxicological hazards are those resulting from exposure to a wide range of chemicals and from chemicals are usually classified active processes. In this study, twenty beauty shops were selected to assess the exposure to indoor air pollutants such as VOCs and particulate matter (PM10) during one month from September 1 to September 30, 2003. Indoor air quality of beauty shops might be worse by vehicle emissions because the beauty shops were generally located near roadway. Personal exposures to VOCs and PM10 were related to indoor concentrations of beauty shops, respectively. According to questionnaire, hairdressers responded sore throat, eye irritation, and nervousness as health effect symptoms. Conclusively, users as well as workers in beauty shop might be highly exposed to air pollutants from indoor sources and outdoor sources. Therefore, proper methods should be prepared to improve the indoor air quality in beauty shop.
The most important factors relating to the indoor air environment are temperature, airflow, humidity, and contaminant concentration. A sensitivity analysis of indoor environment factors was carried out to grasp influences along with changes of atmospheric conditions. An integrated multizone model was used to predict these sensitivities. This model was applied to an apartment with six zones.
Airflow rates are influenced very seriously by changes of wind direct or wind velocity, but are influenced very slightly by changes of outdoor air temperature and are not influenced at all by changes of outdoor air humidity or contaminant concentration.
Indoor air temperatures are influenced very directly by changes of outdoor air temperature, but are influenced very slightly by wind direction or wind velocity and are not influenced at all by changes of outdoor air humidity or contaminant concentration.
Indoor air humidities are influenced very directly by changes of outdoor air humidity, but are not influenced at all by changes of outdoor air contaminant concentration and have little or no influence by changes of wind direction, wind velocity, or outdoor air temperature.
Indoor air contaminant concentrations are influenced very seriously by changes of wind direct or wind velocity, but are influenced somewhat by changes of outdoor air contaminant concentration and are influenced very slightly by changes of outdoor air temperature and are not influenced at all by changes of outdoor air humidity.
The work of hairdressers includes washing, coloring, bleaching, permanent waving, conditioning, and cutting hair. Hairdressers are subjected to a number of physical and toxicological hazards. The toxicological hazards are those resulting from exposure to a wide range of chemicals that are usually classified active processes. In this study, twenty beauty shops were selected to assess the exposure to indoor air pollutants such as VOCs and particulate matter (PM10) during one month from September 1 to September 30, 2003. Indoor air quality of beauty shops might be worse by vehicle emissions because the beauty shops were generally located near roadways. Personal exposures to VOCs and PM10 were related to indoor concentrations of beauty shops. According to the questionnaire, hairdressers complained of sore throat, eye irritation, and nervousness as physical symptoms. The measured mean concentrations of respiratory particulates were 30.5ng/㎥ in indoor, 30.5ng/㎥in outdoor and 44.0ng/㎥ on personal levels. The personal concentration was found higher than indoor and outdoor concentrations. The heavy metals mean concentrations were shown as indoor (Na>Zn>Cr), outdoor (Cr>Zn>Pb), and personal (Na>Cr>Zn) levels. Conclusively, customers as well as workers in the beauty shops might be highly exposed to air pollutants from indoor and outdoor sources. Therefore, proper management should be taken to improve the indoor air quality in beauty shops.
Chloroform present in the swimming water disinfected with sodium hypochlorite is released to the air of swimming pools. The air chloroform concentrations were measured in two swimming pools A and B which applied both sodium hypochlorite and ozone. Their mean concentrations are 28.0 ㎎/㎥ and 33.6 ㎍/㎥ in the swimming pools A and B, respectively. On the other hand, the mean water chloroform concentrations in the swimming pools A and B were 23.9 ㎍/ℓ and 19.5 ㎍/ℓ, respectively. The air chloroform concentrations were lower in the swimming pools A and B than those reported by previous studies abroad employed the swimming pools which applied sodium hypochlorte only for water disinfection. The water chloroform concentrations were also lower in this study than in the previous studies. The relationship between the air and water chloroform concentrations measured in this study was significant with p=0.002 and R^2=O.42. At similar time to the indoor air sampling, outdoor air samples were collected at two sites near each of the swimming pools A and B. The mean outdoor air chloroform concentrations near the swimming pools A and B were 0.41 ㎍/㎥ and 0.16 ㎍/㎥, respectively. The outdoor air chloroform concentrations measured in this study were equal to or lower than those reported by previous studies abroad. The chloroform dose inhaled for a typical one-hour swim was estimated to be 25.9 ㎍ per person, corresponding to a specific 0.37 ㎍/㎏ body weight. for a reference 70 ㎏ male adult, while the inh lation dose of chloroform from the outdoor air was estimated to be 5.6 ㎍ per person per day, corresponding to a specific 0.08 ㎍/㎏/day for the same reference male adult.