🔍 Key Concepts

• Difference between control air and service air on a ship • Purpose of forced draft air in a boiler or engine room • What is meant by air used "primarily to the combustion control system and other pneumatic controllers"

💭 Think About

• Which type of air system is dedicated to delicate instruments and automatic control devices, where clean, dry, stable pressure is critical? • Which system name would you expect for air used for general utility work like tools and cleaning, rather than sensitive controls? • Does "forced draft" describe air for controls, or air used directly in the combustion process (into the furnace/engine)?

✅ Before You Answer

• Identify which option best matches an air system used specifically for control and instrumentation rather than general services. • Eliminate any option that mainly refers to air supplied to the burners/furnace as combustion air rather than to controllers. • Check that the chosen system name would normally require dry, oil-free, reliable air for accurate operation of pneumatic controllers.