Appearance inspection and power on test to observe whether the packaging is complete, whether there is any damage or squeezing. Observe the overall appearance of the product to see if it matches the diagram. Are the instructions, warranty cards, etc. complete. Plug it in and use it to see if it can work properly. Two detection methods (1) Health and safety testing. (Soaking test) Rinse the water purifier with tap water for half an hour and let it dry. Then rinse with pure water, add pure water, and soak in a closed container for 24 hours. Check the water quality of the soaking water and the pure water quality inside the container. The increase in certain items (harmful impurities) (dissolved substances) should not exceed the standard; (2) Hygienic functional testing, functional testing (including labeling tests). Connect the water purifier to tap water and operate according to the flow rate specified in the manual until the rated total water purification volume specified in the manual is completed At the beginning and end of operation, check the effluent quality of the water purifier; ② At the initial, 1/4, 1/2, 3/4, and final stages of operation, a total of five sections are subjected to standard addition tests. The manually prepared standard addition water is used as the inlet water of the water purifier to detect the quality of the inlet and outlet water of the water purifier and assess its ability to remove specific substances (removal rate). For example, water purifiers with activated carbon require organic matter labeling to assess their removal rates for volatile phenols, chemical oxygen consumption, chloroform, and carbon tetrachloride in water; The ultrafiltration water purifier needs to be labeled for turbidity and total coliform bacteria, and its removal rate for turbidity and total coliform bacteria should be evaluated. The key to water purifiers - activated carbon filter cartridges are the most commonly used water purification components for various household water purifiers, and their quality is particularly important. The quality of activated carbon and activated carbon filter elements is a key factor that directly affects the overall quality and hygiene safety of water purifiers. Hu Junming, Director of the Environmental and Health Related Product Safety Institute of the China Center for Disease Control and Prevention, and other experts have written an article pointing out that according to the testing data of different types of household water purifiers conducted by the institute from 2006 to 2009, the failure rate of various types of activated carbon filters is relatively high. The unqualified rate of particle activated carbon filter element is 10.7%; The unqualified rate of sintered activated carbon filter element is 25%; The unqualified rate of activated carbon fiber filter element is 15.4%