1990年 6月 ,笔者接到绸厂医院报告 ,近期有部分职工被一种小虫叮咬 ,出现红肿、搔痒等症状 ,有的不能正常工作。为此 ,立即前往进行现场调查。1　基本情况　该宿舍楼建于 50年代 ,共 3层 ,面积约 34 0 0ｍ2 ,大部分为女工宿舍 ,上下铺 ,居住拥挤 ,且室内空气质量较差 ,湿度大 In June 1990, the author received a report from Silk Factory Hospital that some workers were bitten recently by an insect and showed symptoms such as redness, itching and so on, and some of them could not work normally. To this end, immediately went to the scene investigation. 1 The basic situation The dormitory was built in the 50’s, a total of 3 layers, an area of ​​about 3400m2, most of the female dormitory, bunk beds, living crowded, and poor indoor air quality, humidity