3 the collection of samples
3.1 source water （superficial water、spring water、well water ）
3.1.1 when taking the source water as samples, please use the special instrument for source water
3.1.2 You can sample the sprayed spring water directly from the spout,If you sample the still spring water, you should empty the pipe , and replace it with fresh water.If you sample the well water,you’d better tap enough water to keep the samples representative.
3.2 drinking water(treated water、terminal tap water、secondary supplied water )
3.2.1 when sampling above waters,you should sterilize the water outlet（stopcock）with alcohol cotton balls from center to every sides, then running the water for several minutes to empty the impurities and old water in the pipe.
3.2.2 ①You should sample directly for microorganism detection, not wash the sterilized collectors with sampling water , and avoid the pollution of bottleneck with your fingers and other materials.
② When you sample for physical testing and chemical analysis, you should wash the collector 、container and stopper with sample water for 2 to 3 times before sampling.