🔍 Key Concepts

• Function of plumbing traps in marine and household systems • How water seals work to block certain things from moving back through a pipe • Difference between flow problems (like clogging) and environmental/comfort issues (like smells or sounds)

💭 Think About

• Ask yourself: What is actually held inside a trap, and what is it stopping from moving back up the pipe? • Which choice describes something that would move from the drainage system back toward the living spaces if the trap were not there? • Think about typical problems on older boats or buildings when traps dry out—what do people usually complain about?

✅ Before You Answer

• Identify what a water seal in a trap is designed to block from returning to the compartment or living space. • Rule out choices that deal mainly with flow efficiency (how smoothly water moves) versus what traps are really meant to control. • Consider which issue is most directly related to habitability and sanitation rather than mechanical performance.