Verify Official Authoritative Data (The Fundamental Prerequisite)
Check third-party test reports: Ensure the report clearly states a residual chlorine removal rate of ≥90% and specifies removal rates for key contaminants like heavy metals and suspended solids. Confirm the testing agency holds CNAS accreditation to avoid products with exaggerated specifications.
Confirm water-contact safety certifications: The product must hold a national hygiene and safety permit for water-contact products. The housing and water-contact components must pass GB4806 food-grade certification to eliminate safety risks such as heavy metal leaching in hot water.
Check rated filtration capacity: The report should clearly specify the rated filtration capacity at standard flow rates and the filter cartridge performance decay curve, rather than using vague terms like "depends on water quality." This prevents premature filtration failure caused by exaggerated filter lifespan claims.
Low-Cost Practical Home Tests (Intuitive and Actionable)
Residual chlorine comparison test: Use an OTO residual chlorine test card or reagent. Collect equal amounts of unfiltered tap water and filtered water, add the same amount of reagent to each, and compare the colors. If the raw water turns noticeably yellow while the filtered water remains colorless, the chlorine removal is effective; if the filtered water still appears yellow, the filter media is saturated or ineffective.
Visual inspection of water quality: Collect filtered water in a clear glass and hold it against the light to check for suspended impurities; ensure no sediment forms at the bottom after standing for 3 hours. If the raw water has a yellowish-brown rust tint but becomes clear and transparent after filtration, the physical filtration layer is functioning correctly.
Odor and skin feel verification: Tap water often has a distinct smell of bleaching powder, which should disappear completely after filtration. After 1–2 weeks of continuous use, effective filtration is indicated if your skin no longer feels dry or itchy after showering and your hair is less prone to tangling or dryness.
