Why is there a biological risk with cooling towers?

• A. Potential growth of Legionella bacteria in aerosols.
• B. Accumulation of lead particles.
• C. Corrosion of metal surfaces.
• D. Increased oxygen depletion.

Answer: (A)

The main risk in cooling towers is inhaling aerosolized water that may contain bacteria, particularly Legionella. Cooling towers spray water into the air as fine droplets; if the tower water harbors Legionella and isn’t properly disinfected or cleaned, these bacteria can multiply in the warm, sometimes stagnant water and become incorporated into the aerosols. When people nearby inhale those aerosols, they can develop Legionnaires’ disease, a serious form of pneumonia. This is why cooling towers require vigilant water treatment, regular cleaning, and measures to minimize aerosol release.

Other options involve non-biological concerns. Lead particles would be a chemical contamination issue, corrosion relates to material degradation and equipment integrity, and oxygen depletion is a water-quality problem not directly tied to the inhalation risk from aerosols. The biological danger specifically stems from aerosolized water carrying Legionella.