최근 WHO(세계보건기구)에서 미세먼지를 1급 발암물질로 분류하면서 미세먼지의 위험성이 대두되었다. 이에 따라 사람들은 가족단위의 야외활동을 줄이고 실내에서의 쇼핑이나 외식활동을 선호하고 있는 추세이다. 그러나 이렇게 실내로 사람들이 몰리면서 실내미세먼지의 위험성 또한 간과할 수 없는 상황이며, 실내미세먼지농도가 사람에게 위해하지 않은 수치인지 등에 대한 연구사례 또한 충분하지 않은 실정이다. 따라서 본 연구에서는 가족단위의 사람들이 많이 이용하는 250석 수용규모 음식점의 실내미세먼지농도(PM10, PM2.5)를 측정하였다. 그리고 실외미세먼지농도, 실내 방문객 수, 실내 주방요리가 필요한 스테이크 조리 주문건수에 대하여 어떠한 요인이 실내미세먼지농도 가장 영향을 주는지 비교분석 하였다. 또한 실험을 통해 자연환기, 공기청정기 또는 환기장치 사용 중에 실내미세먼지농도 저감에 가장 우수한 것이 무엇인지 알아보고자 하였다. 그 결과는 아래와 같다.

1. 7월∼9월 실내미세먼지농도 PM10의 측정결과 국내 기준 대비 약 1.8∼2.2배, 국외 WHO 기준 대비 3.6∼4.0배, PM2.5의 경우 국내 기준 대비 약 3.1∼5.2배, 국외 WHO 기준 대비 약 8.6∼10.2배 초과하는 것으로 나타났다. 특히 3개월 동안 PM10의 최대 농도에 비해 PM2.5의 최대 농도가 더욱 높게 나타나 미세먼지로 인한 문제가 심각하다고 사료된다.

2. 7월∼9월 실외미세먼지농도는 국내 기준 PM10 150 과 PM2.5 50 로 모두 기준 이하였으나 WHO 기준인 PM10 50 과 PM2.5 25 에 비해 PM10은 2∼26 PM2.5는 14∼38 만큼 기준을 초과하였다. 실외미세먼지농도와 실내미세먼지농도와 비교한 결과 측정기간 중 1개월에 1일∼3일은 서로 미세먼지농도가 비슷한 양상을 나타났으나 이를 제외한 날짜에서는 미세먼지농도 PM10은 최대 10.6배, PM2.5는 최대 91배 차이가 나는 등 실내·외 미세먼지농도차이는 크게 다른 것으로 나타났다. 따라서 실외미세먼지농도와 실내미세먼지농도는 큰 영향이 없는 것으로 사료된다.

3. 7월∼9월 음식점 평균 방문객 수는 19명∼81명이며 이때 평균 실내미세먼지농도 PM10은 13∼89, PM2.5는 22∼114 로 나타났다. 평균 방문객 수가 많은 시간대는 13시와 20시로 점심과 저녁시간인 것을 확인하였다. 평균 실내미세먼지농도가 가장 높은 시간은 20시로 PM10은 64∼77 PM2.5는 91∼114 ,평균 실내미세먼지농도가 가장 낮은 시간은 7월과 9월은 13시, 8월은 17시로 PM10은 13∼14 PM2.5는 22∼23로 나타났다. 평균 실내미세먼지농도는 저녁시간에 높게 나타났으며, 점심시간에는 평균 방문객 수가 많음에도 불구하고 높게 나타나지 않았다. 따라서 방문객 수의 변화가 실내미세먼지농도에 큰 영향을 주는 것은 아닌 것으로 사료된다.

4. 스테이크 주문건수는 방문객 수가 약 700명인 일요일에 약 98건으로 가장 많았으나 방문객 수 대비 스테이크 주문건수는 약 14∼18%에 그치는 것으로 나타났다. 그러나 평일에는 방문객 수가 약 350명으로 일요일에 비해 절반 정도 수준이나 스테이크 주문건수가 약 71건으로 방문객수 대비 스테이크 주문건수는 약 21∼23%로 높게 나타났다. 특히 8∼9월 공휴일에는 방문객수가 700명 이상 이었으나 실제 스테이크 주문건수는 58건으로 방문객 수 대비 스테이크 주문건수는 약 8%에 불과한 것으로 나타났다.

5. 7∼9월 스테이크 주문건수에 따른 실내미세먼지농도에 대한 데이터를 종합하여 추세선을 나타낸 결과 결정계수(R2)가 0.92∼0.95로 1에 가깝게 나타나 스테이크 주문건수와 실내미세먼지농도는 거의 비슷한 양상임을 확인하였다. 따라서 주방 조리가 필요한 스테이크의 주문건수와 실내미세먼지농도는 서로 밀접한 관계가 있는 것으로 사료된다.

6. 미세먼지 저감 실험에서 재실인원 5명이 실험 장소에 앉아 있거나 가벼운 움직임이 있는 정도일 때 실내미세먼지농도는 PM10은 31, PM2.5는 10.8로 나타났다. 자연환기를 하였을 때 평균 실내미세먼지농도 PM10은 20.1 으로 평균제거율은 35.2%, PM2.5는 7.3 로 평균제거율은 32.4%로 나타났다. 공기청정기를 사용할 경우 평균 실내미세먼지농도 PM10은 22.4 으로 평균제거율은 27.7%, PM2.5는 8.3 로 평균제거율은 23.1%로 나타났다. 자연환기를 사용하거나 공기청정기를 사용하였을 때 평균 실내미세먼지농도 PM10은 2.3 , PM2.5는 1.0 로 거의 차이가 나지 않았다. 평균제거율은 자연환기를 사용하였을 때가 공기청정기를 사용하였을 때 보다 실내미세먼지농도 PM10은 7.5%, PM2.5는 9.3%로 다소 차이가 있었으며, PM10보다 PM2.5의 평균제거율이 더 좋은 것으로 나타났다.

7. 스테이크 요리 시 공기청정기만 사용하였을 때 실내미세먼지농도 평균제거율은 PM10은 19.1∼24.3%, PM2.5는 22.8∼29.4%, 환기장치만 사용하였을 때 실내미세먼지농도 평균제거율은 PM10은 41.9∼61.2%, PM2.5는 45.0∼68.6%임을 확인하였다. 환기장치를 사용하였을 때가 공기청정기를 사용하였을 때보다 실내미세먼지농도 PM10은 22.8∼36.9%, PM2.5는 22.2∼39.2%더 저감시켜 더욱 효과가 있는 것으로 나타났다. 한편 공기청정기와 환기장치를 동시에 사용하였을 경우 실내미세먼지농도 평균제거율은 PM10은 67.4∼73.1%, PM2.5는 52.6∼78.2%로 환기장치만 사용하였을 때보다 실내미세먼지농도 PM10은 11.9∼25.5%, PM2.5는 7.6∼9.6% 더 효과가 뛰어난 것을 확인하였다.

연구결과 음식점에서 실내미세먼지농도에 가장 큰 영향을 미치는 것은 실내 주방 조리로 인한 요인으로 나타나났다. 미세먼지저감 실험 결과 가장 효과가 좋은 방법은 공기청정기와 환기장치를 동시에 사용하는 것이며, 그 다음은 환기장치 사용, 효과가 적은 방법은 공기청정기만 사용하는 것으로 나타났다. 따라서 음식점에서 조리를 할 때에는 환기장치를 사용하거나 공기청정기를 추가하여 함께 사용하는 것이 가장 실내미세먼지농도를 줄이는 방법이라 사료된다. 또는 개방형 주방을 독립적으로 구성하여 음식점 내의 미세먼지농도에 영향을 주지 않도록 하는 것이 합리적이라 판단된다.

Recently the fine dust of WHO (World Health Organization) has been classified as a first carcinogen and the risk of fine dust has emerged. With this, people tend to reduce outdoor activities on a family basis, preferring to shop indoors and eating out activities. However, in such a situation, people are concentrated in the room, the danger of indoor fine dust can not be overlooked, and research cases such as indoor dust concentration not being harmed to human beings are not enough It is a fact. Therefore, in this study, the indoor dust concentration (PM 10, PM 2.5) of a restaurant with a capacity of 250 seats, which is frequently used by people in the family unit, was measured. And outdoor dust concentration, indoor visit, all the factors concerning the number of steak dish orders requiring indoor kitchen cuisine affect the most influence on indoor dust concentration was compared and analyzed. Also, through experiments, let''s examine what is the best thing to reduce indoor dust concentration while using natural ventilation, air purifiers and ventilation equipment. The results are as follows.

1. Measurement result of indoor dust concentration PM 10 from July to September Approximately 1.8 to 2.2 times the domestic standard ratio, 3.6 to 4.0 times the overseas WHO standard ratio, about 2.5 to 5.2 times compared to the domestic standard for the PM 2.5, compared with the domestic standard WHO It was found that it exceeds about 8.6 to 10.2 times compared with the standard. Especially during the 3 months the maximum concentration of PM 2.5 appears even higher than the maximum concentration of PM 10, and the problem caused by fine dust is considered to be serious.

2. Outdoor dust concentration was lower than the criteria for both domestic standard PM 10150 and PM 2.550 in July to September but compared with PM 1050 and PM 2.525 which is the WHO standard, PM 10 is 2 to 26 PM 2.5 is 14 ~ 38 exceeded the standard. As a result of comparison between the outdoor dust concentration and the indoor dust concentration, the concentration of the fine dust was similar to each other during the measurement period from 1 day to 3 days a month, but on other days, the dust concentration It was found that the difference in indoor / outdoor dust concentration greatly varied, such as maximum 10.6 times PM 10 and maximum 91 times difference of PM 2.5. Therefore, it is considered that the outdoor dust concentration and the indoor dust concentration have no significant influence.

3. From July to September, the average number of visitors to restaurants was 19 to 81 people, and the average indoor dust concentration PM10 at this time was 13 to 89, and PM 2.5 was 22 to 114. We confirmed that the hours during which the average number of visitors is high are 13:00 and 20:00, the time of lunch and dinner. Time with the highest average indoor dust concentration is 20 o''clock PM 10 is 64 to 77 PM 2.5 is 91 to 114, the average indoor dust concentration is the lowest at 13 o''clock in July and September, and 7 o''clock PM 10 in August 13 - 14 PM 2.5 was 22 - 23. The average indoor dust concentration appeared very much in the evening time, and at lunch time, despite the large number of average visitors, it was not displayed very much. Therefore, it is considered that the change in the number of visitors will not have a significant influence on the indoor dust concentration.

4. The number of steak orders was the largest at about 98 visits on Sundays with about 700 visitors, but it turned out that the number of steak orders was only about 14 to 18% compared to the number of visitors. However, on weekdays the number of visitors was about 350 people compared with Sunday level and the number of steak orders was about 71, compared to the number of visitors, the number of steak orders was high at about 21 to 23%. Especially in the period from August to September the number of visitors was over 700 on holidays, but the actual number of steak orders could be visited with 58 cases and it turned out that the number of orders for steaks was only about 8% .

5. The data on the indoor dust concentration corresponding to the number of steak orders was compiled from July to September and the number of display steak orders and the indoor dust concentration which are close to 1 with the result determination coefficient (R2) showing the trend line of 0.92 to 0.95 are almost It was confirmed that it was a similar surface. Therefore, it is considered that the number of orders of steaks that require kitchen cooking and the indoor dust concentration are closely related to each other.

6. In a fine dust reduction experiment sitting at the experimental place of 5 people in the room, or in some cases of light movement, the indoor dust concentration was 31 days for PM 10 and 10.8 for PM 2.5.The average indoor dust concentration PM 10 was 20.1 when natural ventilation was performed, the average removal rate was 35.2%, the PM 2.5 was 7.3, and the average removal rate was 32.4%. When using an air purifier, the average indoor dust concentration PM10 was 22.4, the average removal rate was 27.7%, the PM 2.5 was 8.3, and the average removal rate was 23.1%. The average indoor dust concentration PM 10 when natural ventilation was used or when using an air purifier was 2.3, and the PM 2.5 was 1.0, showing almost no difference. The average removal rate was slightly different between the indoor dust concentration PM 10 of 7.5% and the PM 2.5 of 9.3% than when using the air purifier when natural ventilation was used, and there was some difference between the PM 10 and the PM 10 It was found that the removal rate was better.

7. When only the air cleaner at the time of steak cooking was used, the average removal rate of indoor dust concentration was 19.1 to 24.3% for PM 10, 22.8 to 29.4% for PM 2.5, and when only the ventilator was used, room dust It was confirmed that the average removal rate of the concentration was 41.9 to 61.2% for PM 10 and 45.0 to 68.6% for PM 2.5. It was found that the indoor dust concentration PM 10 was reduced from 22.8 to 36.9% and the PM 2.5 was reduced from 22.2 to 39.2% as compared with the case of using the air cleaner when the ventilator was used and it was found to be more effective. On the other hand, when using an air cleaner or a ventilator at the same time, the average removal rate of the indoor dust concentration was 67.4 to 73.1% for PM 10 and 52.6 to 78.2% for PM 2.5, which is lower than the case where only the ventilator was used, Concentration PM 10 was confirmed to be 11.9 to 25.5%, PM 2.5 to be 7.6 to 9.6%, and it was confirmed that the effect was more excellent.

Results The greatest influence on indoor dust concentration at restaurants was shown as a factor due to indoor kitchen cooking. As a result of experiment for reducing fine dust, the most effective method is to use air purifiers and ventilators at the same time, the next step is to use ventilation equipment, the less effective way is to use air purifier only I understood. Therefore, when cooking in a restaurant, using a ventilator or adding an air purifier is considered to be the most effective way to reduce indoor dust concentration. It is judged that it is reasonable to independently configure the open kitchen so as not to affect the dust concentration of the restaurant.