Point-of-use activated carbon filters are most effective for removing ______.

• A. Volatile organic chemicals
• B. Microorganisms
• C. Radon
• D. Chlorine

Answer: (D)

Activated carbon works by adsorption, using its extensive porous surface to trap molecules as water passes through. This makes it especially good at removing compounds that affect taste and odor. Chlorine is a simple, volatile molecule that readily moves into the carbon’s pores, so its concentration in water drops quickly, leaving water that tastes and smells better. Microorganisms aren’t removed by this adsorption process, so disinfection or microfiltration is needed for that. Radon is a gas that carbon filters don’t reliably remove. Some VOCs can be reduced, but the most consistent and noticeable improvement with typical point‑of‑use carbon filters is chlorine removal.