🔍 Key Concepts

• Purpose of traps in plumbing systems on vessels and in buildings • Role of water seal in a drain trap • How plumbing design protects against sewer gases and unsanitary conditions

💭 Think About

• When water sits in the curve of a trap, what is it blocking or separating? • Which problem would be most related to crew comfort and sanitation rather than mechanical performance of the pipe? • Think about what comes from sewage tanks or shore sewer lines that you definitely do NOT want entering living spaces.

✅ Before You Answer

• Identify what a water seal specifically prevents from passing through the drain • Focus on hazards to health, comfort, and habitability of living quarters • Eliminate options that deal mainly with noise or flow efficiency instead of hygiene and air quality