You absorb 6 to 100 times more chlorine in a shower than you do by drinking the same water. For almost 100 years, chlorine has been added to disinfect our municipal water supply. The level of chlorine in your area depends on the quality of your water supply, but even if there is no noticeable smell, the chlorine may still be present. Chlorine absorbed in the shower dries the skin, decolorizes and causes brittle hair, causes eye irritation and inhaling chlorine vapors can cause an allergic reaction. Replacement Filter Schedule - Approximately every 6 months depending on level of water contamination.