평택항 자동차 선적작업장의 공기오염 실태조사

Abstract

[한글]

자동차 선적 작업장의 공기오염도를 알아보기 위하여 옥외작업장인 야적장과 옥내작업장인 선박내 진입로를 선정하여 아황산가스, 이산화질소, 일산화탄소, PM10, PM2.5와 중금속의 기중 농도를 측정하여 다음과 같은 결과를 얻었다.

자동차 선적작업의 옥외작업장과 옥내작업장의 온도와 습도는 유의한 차이가 없었으며 기류는 옥내작업장이 평균 0.52m/s로 옥외작업장의 평균 0.19m/s보다 높았다(p<0.01). 작업장소에 따른 아황산가스, 이산화질소, 일산화탄소, PM10, PM2.5의 각각 평균 농도는 옥외작업장의 경우 0.031ppm(±0.012), 0.028ppm(±0.009), 0.460ppm(±0.220), 39.440㎍/㎥(±2.445), 5.450㎍/㎥(±1.148)이었고 옥내작업장에서는 0.152ppm(±0.045), 0.217ppm(±0.064), 8.850ppm(±3.348), 236.390㎍/㎥(±58.214), 152.430㎍/㎥(±35.419)으로 측정되었다. 옥내작업장은 옥외작업장보다 가스상물질 농도가 4.9~19.2배, 미세먼지 농도는 5.9~27.9배 높았다(p<0.01). 또한 선박내 휘발유 자동차 선적 작업시 배기량 및 주차대수에 따른 오염물질의 농도를 조사한 결과 승용차(Passenger car)는 주차대수와 오염물질간에 유의한 차이가 없었고, 레져용 차량(Recreational vehicles)은 주차대수가 많을수록 이산화질소와 일산화탄소의 농도가 높았으며(p<0.05), 승용차보다 배기량이 큰 레져용 차량에서는 이산화질소, 일산화탄소, PM10, PM2.5의 기중농도가 통계학적으로 유의하게 높았다(p<0.01).

한편 옥내작업장인 선박내의 기중 중금속 평균 농도는 납이 0.050㎍/㎥(±0.100), 크롬은 0.900㎍/㎥(±0.183), 아연은 0.375㎍/㎥(±0.236), 구리는 0.175㎍/㎥(±0.222) 그리고 망간과 카드뮴은 불검출 되었다. 또한 만성호흡기질환의 주요 증세인 ‘천식’의 자각증상 호소율은 옥외와 옥내작업자에서 각각 18.5%, 22.5%로 조사되어 옥내작업자가 다소 높은 결과를 보였으나 유의한 차이는 없었다. ‘만성기침’과 ‘만성가래’의 자각증상 호소율은 매우 낮은 수준으로 옥내·외 근로자간에 차이가 없었다.

이상의 결과에서 옥외작업장보다 선박내의 옥내작업장 공기오염도가 높은 이유는 선박내 차량 이동시 급출발 및 과속으로 인한 불완전연소가스의 발생량이 많기 때문이며 이를 방지하기 위한 대책으로 적정속도의 준수와 노후된 선박의 정비 그리고 원활한 공조시스템을 갖추는 등의 효율적인 관리방안이 필요하다.

[영문]This study purposed to investigate air pollution in car shipping yards and, for this purpose, we selected an outdoor open-air yard and an indoor ramp into the ship and measured the concentrations of sulfur dioxide gas, nitrogen dioxide, carbon monoxide, PM10, PM2.5 and heavy metals in the air. The results of this study are as follows.

No significant difference was observed in temperature and humidity between the outdoor workshop and indoor workshop, and the average air flow was 0.52m/s in the indoor workshop, which is higher than 0.19m/s in the outdoor workshop (p<0.01). The average concentrations of sulfur dioxide gas, nitrogen dioxide, carbon monoxide, PM10 and PM2.5 according to workplace were 0.031ppm(±0.012), 0.028ppm(±0.009), 0.460ppm(±0.220), 39.440㎍/㎥(±2.445) and 5.450㎍/㎥(±1.148) respectively in the outdoor work place, and 0.152ppm(±0.045), 0.217ppm(±0.064), 8.850ppm(±3.348), 236.390㎍/㎥(±58.214) and 152.430㎍/㎥(±35.419) respectively in the indoor work place. Thus, the concentrations of gaseous substances in the indoor workshop were 4.9~19.2 times higher than those in the outdoor workshop, and the concentrations of fine dusts were 5.9~27.9 times higher (p<0.01). In addition, according to the result of investigating pollutant concentrations according to displacement and the number of car loaded when shipping gasoline cars into the ship, no significant relation between the number of cars loaded and pollutants was observed in shipping passenger cars, but the concentrations of nitrogen dioxide and carbon monoxide got somewhat higher with the increase of the number of cars loaded (p<0.05). In addition, the concentrations of nitrogen dioxide, carbon monoxide, PM10 and PM2.5 in the air were significantly higher when shipping recreational vehicles, the displacement of which is larger than passenger cars, than when shipping passenger cars (p<0.01).

On the other hand, the average heavy metal concentrations of the air in indoor workshop were: lead - 0.050㎍/㎥(±0.100); chromium - 0.900㎍/㎥(±0.183); zinc - 0.375㎍/㎥(±0.236); copper - 0.175㎍/㎥(±0.222); and manganese and cadmium - not detected.

In addition, the complaining rates of ''asthma,'' a major symptom of chronic respiratory diseases, were 18.5% and 22.5% respectively in indoor workers and outdoor workers. Thus the rate was somewhat higher in indoor workers but the difference was not statistically significant. The complaining rates of ''chronic cough'' and ''chronic phlegm'' were very low and little different between indoor and outdoor workers.

The results of this study show that the reason for the higher air pollution in indoor workshop than in outdoor workshop is incomplete combustion of fuel due to sudden start and over-speed when cars are driven inside the ship. In order to prevent high air pollution, efficient management measures should be taken including the observance of the optimal speed, the improvement of old ships and the installation of efficient ventilation system.