🔍 Key Concepts

• Operation of marine distilling (evaporator) plants and what is actually being measured or sensed • Difference between quantity (flow/volume) and quality (purity/salinity) of produced water • Why even a small amount of salt in potable or boiler feedwater is a serious concern

💭 Think About

• Ask yourself: What does a salinity cell actually detect—how salty the water is, or how much water is flowing? • Think about the main danger if a distilling unit fails—are we more worried about not making enough water, or about salty water getting into systems that require fresh water? • Which of the choices describe direct functions of a salinity cell, and which would only be known by other instruments, like flowmeters or level gauges?

✅ Before You Answer

• Verify what physical property a salinity cell measures (e.g., conductivity related to dissolved salts). • Check which answer choices deal with purity/salt content versus simple volume/amount produced. • Consider whether one device is realistically used to monitor both quantity and quality at the same time in a ship’s distilling plant.