进行了中试工厂研究，以确定慢速砂滤器清除贾第虫囊肿的效率。研究的其他变量包括浊度、颗粒物、总大肠菌群和标准平板计数细菌。这些因变量是根据设计和操作条件的影响进行评估的，如水力负荷率、囊肿浓度、细菌浓度、滤床中沙子的生物成熟度、schmutzdecke的年龄和温度。过滤器几乎去除了100%的贾第虫囊肿、96%的标准平板计数细菌和90%- 百分之八的粒子。由于慢速砂滤的效率和被动性，该技术特别适用于小型水系统。包括24篇参考文献；桌子；数字。

Pilot-plant studies were undertaken to determine the efficiency of slow-rate sand filters in removing Giardia cysts. Other variables studied were turbidity, particles, total coliform bacteria, and standard plate count bacteria. These dependent variables were evaluated with respect to the influence of design and operating conditions such as hydraulic loading rate, the concentration of cysts, the concentration of bacteria, the biological maturity of sand in the filter bed, the age of the schmutzdecke, and temperature. The filters removed virtually one hundred percent of the Giardia cysts, ninety-six percent of the standard plate count bacteria, and ninety-eight percent of the particles. Because of the efficiency and the passive nature of slow-rate sand filtration, this technology is especially appropriate for small water systems. Includes 24 references;tables;figures.