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Measuring residual chlorine concentration
Measuring electrical conductivity
Staff of the Bureau of Waterworks, employees of supervised organizations or private companies with expertise in the field
This fiscal year about 300,000 checks are to be conducted in an area that includes portions of the 23 special wards and 26 municipalities.
*1This measurement shows the effectiveness of chlorine which is added to tap water for disinfection purposes to protect against pathogenic bacteria, including those that cause communicable diseases. By measuring the level of concentration, we can confirm that the customer’s home is being supplied with safe, clean water.
*2This test measures the level of electric conductivity of the water sample taken to confirm that Tokyo’s safe and delicious water is reaching the customer.