■Main points to check on each class day 1. Free residual chlorine: At least 0.1 mg/L from the tap water (if there is a significant risk of contamination from pathogenic microorganisms in the water source, at least 0.2 mg/L) 2. Appearance, odor, taste: No abnormalities 3. Water coolers, etc.: Water from storage water supply equipment should be managed in the same way as tap water ■Which faucet to measure? Measure at the tap at the end of the water supply system. In buildings with elevated water tanks, the lowest floor is the endpoint; in buildings without elevated water tanks, the top floor is the endpoint. If there are multiple elevated water tanks, check each system separately. ■What if chlorine is not detected? Run the water for about 5 to 10 minutes to flush out the water that has accumulated in the supply pipes, then measure again. ■Inspecting the water supply route If the standards are still not met, investigate by taking samples directly from the elevated water tank or receiving tank to determine where chlorine levels are decreasing or if contamination is occurring. ■What to do after long breaks?! After long periods of non-use, such as summer or winter vacations, especially run the water for a longer time before checking free residual chlorine, color, turbidity, odor, and taste.

■10 Items for Regular Inspection For drinking water sourced from tap water, general bacteria, E. coli, chloride ions, organic matter (TOC), pH value, taste, odor, color, turbidity, and free residual chlorine are inspected once a year for each academic year. If there is a water storage tank, inspections will be conducted by system. ■Is Regular Inspection Required for Direct Water Supply? Direct water supply is exempt from regular inspections because the supplier conducts water quality tests and the school performs daily checks. ■Using Well Water or Rainwater Increases the Frequency! When using sources like well water, inspections will be conducted according to the items and frequency applicable to dedicated water supply, while rainwater and other utility water will be tested for 5 items, including pH value and E. coli, twice a year for each academic year. ■Does Water Quality Deteriorate with Fewer Students? If the amount of water used decreases, the daily turnover rate of the water in the storage tank may drop, leading to the disappearance of residual chlorine and a potential decline in water quality. In such cases, a review of the effective capacity of the storage tank or consideration of modifications to direct water supply will be undertaken. ■Records are Kept for 5 Years and 3 Years Records of regular inspections are kept for 5 years. Daily inspection records should be maintained, with efforts made to keep them for 3 years. We also offer consultations on the selection of chlorine agents. Please feel free to reach out to us for inquiries.