Recently, various gases have been used for domestic use, so that gas explosion has been frequent events in the human trachio-bron-chial tree. Lately we have had a case who was 36 year old man with mediastinal & subcutaneous emphysema due to explosion of aspirated acethylene gas in tracheo-bronchial tree while working at shipyard. As for study on this subject, there was a reasonable explication as in etiological factors of mediastinal & subcutaneous emphysema.
