Eikmann T, Schröder S, Pieler J, Bahr H, Einbrodt H J
Zentralbl Bakteriol Mikrobiol Hyg B Umwelthyg Krankenhaushyg Arbeitshyg Prav Med. 1986 Apr;182(2):216-36.
In order to examine the influence exerted by the differing design of individual water treatment plant units on the emission rate of micro-organisms and the associated degree of exposure to which plant personnel is subjected, measurements were taken at three different types of treatment plants. Measurements were made using "Biotest" RCS Air Samplers. The total count of colonies was determined by means of Agar Strips GK-A (tryptic soy agar). Enterobacteriaceae were quantitatively ascertained using Agar Strips C (MacConkey agar), particular attention being paid to the determination of the coliform bacteria as faeces indicators. Agar Strips S (mannitol salt agar) were used to measure the count of staphylococci using Agar Strips HS (rosa Bengal streptomycin agar). Before taking measurements, the prevailing climatic conditions were recorded. It could be ascertained that the enclosure of the inflow area (screw conveyor pump station and aerated grit removal tank) lead to a considerable increase in the concentration of microorganisms in the air within the housing. The values dropped however, when adequate ventilation was provided. Differing oxygen in the activated sludge tanks - finebubble aeration at the tank bottom or the blowing in of air via centrifugal blowers - lead to large variations in the emission rates. However, the less the waste water is agitated, the lower the emission rates. In the case of fine-bubble aeration, rates which are also normally to be found in the "non-burdened" outside air were even recorded close to the aeration tank. In cases of centrifugal blower, the aeration tank should be covered with a shield. With this type of aeration the waste water is emitted radially towards the walls of the tank. The use of a sprinkler unit on an aeration tank equipped with centrifugal blower - to avoid foam formation on the surface of the water - does not lead to an increase in the already high emission rate. An increase in air pollution through mould fungi from waste water treatment plants could not be found. In conclusion, it can be said that different individual plant unit designs have a large influence on the concentration of micro-organisms in the ambient air of places of work of waste water treatment plant personnel. Emission rates can be limited to such a degree that, even in the immediate vicinity of the plant units, a decrease of micro-organism concentrations can be attained as comparable to the area outside the treatment plant.
为了研究各个水处理厂单元的不同设计对微生物排放率以及工厂工作人员所接触的相关暴露程度的影响，在三种不同类型的处理厂进行了测量。测量使用“Biotest”RCS空气采样器。菌落总数通过GK - A琼脂条（胰蛋白胨大豆琼脂）测定。肠杆菌科通过C琼脂条（麦康凯琼脂）进行定量测定，特别关注作为粪便指示菌的大肠菌群的测定。S琼脂条（甘露醇盐琼脂）用于使用HS琼脂条（孟加拉玫瑰红链霉素琼脂）测量葡萄球菌数量。在进行测量之前，记录当时的气候条件。可以确定，进水区域（螺旋输送机泵站和曝气沉砂池）的封闭导致房屋内空气中微生物浓度显著增加。然而，当提供足够的通风时，数值会下降。活性污泥池中不同的氧气供应方式——池底的微气泡曝气或通过离心鼓风机鼓入空气——导致排放率有很大差异。然而，废水搅拌越少，排放率越低。在微气泡曝气的情况下，甚至在曝气池附近记录到的排放率通常与“未受污染”的室外空气中的排放率相当。在离心鼓风机的情况下，曝气池应覆盖防护罩。采用这种曝气方式时，废水会径向排放到池壁。在配备离心鼓风机的曝气池上使用洒水装置——以避免水面形成泡沫——不会导致本已很高的排放率增加。未发现污水处理厂的霉菌导致空气污染增加。总之，可以说不同的单个工厂单元设计对污水处理厂工作人员工作场所周围空气中的微生物浓度有很大影响。排放率可以限制在这样的程度，即即使在工厂单元附近，微生物浓度也能降低到与处理厂外区域相当的水平。
