Which Coast Guard department is responsible for monitoring halogen residuals in the shipboard potable water system?

• A. Engineering
• B. Medical
• C. Deck
• D. Logistics

Answer: (B)

Monitoring halogen residuals is a health protection duty focused on keeping shipboard potable water safe to drink. The Medical department handles potable water quality and sanitation, including routinely testing chlorine residuals to ensure disinfection is effective and within safe levels. This testing helps prevent microbial growth in tanks and piping as water sits in the system, and they interpret results and coordinate any corrective actions (such as adjusting dosing or maintenance) with Engineering to keep the system functioning properly. Engineering may operate and maintain the disinfection equipment, but the responsibility for monitoring the residuals and ensuring safe drinking water rests with Medical.