A pH value of 5.5 would be ideal for human skin. In the whirlpool, a permanent pH below 6.0 can lead to corrosion. Eye irritations can occur in humans because our tear fluid has a pH value between 7 and 7.5. A permanent pH value above 7.8 can lead to clouding of the water and a pinch on the skin because the skin has a pH value of 5.5. If the pH value exceeds 8.0, lime loss may occur. This lime can cloud the water and settle in the pipes.