本文描述了与30家供水商进行的为期18个月的合作调查的结果，该调查研究了I级和2级湿式喷水灭火系统对配水干管中饮用水的影响。从各种商用湿式喷水灭火系统采集的水样中，水质超过了铅和镉的一级标准以及铁、锰、硫酸盐、颜色、气味和总溶解固体的二级标准。在平均3分钟消防栓流量试验的现场规模回流模拟中，当止回阀在打开位置出现故障时，湿管消防喷淋系统中回流了约100加仑（0.4m3）的水。 据估计，在非住宅火灾中受重伤的相对风险是发生回流后感染水传播疾病风险增加的33倍。改造现有的1级和2级湿式喷水灭火系统，目前没有防回流组件，将在全国范围内花费约44-60亿美元，并被认为不符合成本效益。包括27个参考文献、表格和图表。

This article describes the results of an 18-month collaborative investigation with 30 water purveyors that studied the effects of Class I and Class 2 wet-pipe fire sprinkler systems on drinking water in distribution mains. In water samples taken from a variety of commercial wet-pipe fire sprinkler systems, water quality exceeded the primary standard for lead and cadmium and the secondary standards for iron, manganese, sulfate, color, odor, and total dissolved solids. In field-scale backflow simulations of an average 3-min hydrant-flow test, about 100 gals (0.4m3) of water backflowed from a wet-pipe fire sprinkler system when the check valve was caused to fail in the open position. The estimated relative risk of being seriously injured in nonresidential fires is 33 times as great as the increased risk of contracting a waterborne illness after backflow has occured. Retrofitting existing Class 1 and Class 2 wet-pipe fire sprinkler systems that do not currently have backflow prevention assemblies would cost about $4.4-6.0 billion nationwide and was deemed not cost-effective. Includes 27 references, tables, figures.