广州市秋季室内外大气中细菌气溶胶粒径分布特征

Bacterium aerosol grain-size distribution characteristics indoor and outdoor Guangzhou ordinary residential district room

目的探索广州市细菌气溶胶的分布情况。方法选择灰霾天气期间,采用分粒径采样对广州市普通住宅小区室内外细菌气溶胶进行连续检测,时间为2005年10月19～28日。结果不同楼层、一天中不同时间段,室内细菌气溶胶总数介于204～2530cfu.m-3(几何平均2.72±0.32cfu.m-3),室外细菌气溶胶总数介于95～1717cfu.m-3(几何平均2.53±0.31cfu.m-3)。室内外空气细菌气溶胶粒径分布基本一致,呈偏态分布,其中69.8%～72.9%的细菌气溶胶颗粒沉降在3～6级。结论室内空气细菌总数虽然低于国家标准,但其中约70%的细菌可沉降于人体下呼吸道,空气质量不容乐观。

Objective To Survey the distribution Of bacterium aerosol granules indoors and outdoors in Guangzhou City. Methods In haze weather period between October 19, and 28 2005, the bacterium aerosol granules of various sizes was continuously sampled indoors and outdoors in residential district in Guangzhou using samplers of different particle size. Results The total distribution of bacterium aerosol granules on different floors indoors and outdoors was consistent at different periods of time in a day. The quantity of bacterium aerosol granules indoors were in the range of 204 - 2530 cfu· m^-3 （geometry average 2.72 ± 0.32 cfu· m^- 3 ）, and that of outdoors was in the range of 95 ± 1717 cfu· m^- 3 （geometry average 2.53 ± 0.31 cfu · m^- 3）. The bacterium aerosol grain - size distribution inddors and outdoors was consistent in skewed distribution, with 69.8 % - 72.9 % bacteriumaerosol settling in from grade 3 to grade 6, the granule size was similar to the human lower respiratory tract. Conclusion Although the total count of bacterium indoors is lower than that of the national standard, approximately 70 % of the bacteria subsided in human lower respiratory tract. Thus the air quality is far from being satisfactory.