The present invention relates to a dust mask and, more specifically, to a dust mask capable of preventing a fogging phenomenon, which is generated on a welding surface or safety glasses caused by inner air, by installing a collecting box at an outlet of an exhale port formed in a lower part of a mask body connecting the collecting box and a discharging pipe and discharging the inner air of the mask body discharged to the exhale port above a head of a worker along the collecting box and the discharging pipe. The dust mask comprises: the mask body an inhale port the exhale port a fixing board the collecting box and the discharging pipe. The mask body includes a shape which adheres to an inner surface to block a nose and a mouth. The inhale port is installed in both sides of the mask body and inhales outer air. The exhale port is installed in a lower side of the mask body and exhales the inner air. The fixing board is connected to the both sides of the mask body with a band and covers the head. The collecting box is installed in the outlet of the exhale port and collects the exhaled inner air. One end of the discharging pipe is connected to the collecting box. A length of the discharging pipe is longer than a length of the collecting box and a length of the fixing board to enable the other end of the discharging pipe to be positioned on an upper side of the fixing board. The discharging pipe discharges the inner air in the collecting box above the head. The dust mask is provided to discharge the inner air through the exhale port above the head of the worker, thereby preventing the fogging phenomenon generated on the welding surface and the safety glasses worn by the worker due to the inner air.COPYRIGHT KIPO 2017본 발명은 방진 마스크에 관한 것으로, 더욱 상세하게는 마스크 본체의 하부에 형성된 배기구 출구단에 포집함이 설치되고 포집함에 배출관이 연결되어 배기구로 배출되는 마스크 본체의 내기가 포집함과 배출관을 따라 작업자의 머리 위로 배출됨으로써 내기로 인한 용접면이나 보안경에 발생하는 김 서림 현상을 방지할 수 있는 방진 마스크에 관한 것이다. 본 발명에 따르면, 코와 입을 막도록 안면에 밀착되는 형태를 가지는 마스크 본체 상기 마스크 본체의 양측에 설치되어 외기가 흡
