Question 23 QMED01 - Junior Engineer

The Correct Answer is C **Explanation for Option C (Control Air System):** The term "control air system" specifically refers to the dedicated compressed air network used to power and operate pneumatic instrumentation, such as combustion control systems, boiler feedwater regulators, and other pneumatic controllers (e.g., valves, relays). This air must be extremely clean, dry, and regulated to ensure the accurate and reliable operation of sensitive control components. Since the question states the air is supplied "primarily to the combustion control system and other pneumatic controllers," the correct classification for the entire system is the **control air system**. **Why the Other Options are Incorrect:** * **A) ships service air system:** This system supplies air for general non-critical utility purposes (e.g., powering pneumatic tools, cleaning, deck washing, whistle). While it may supply the intake for the control air system's dryer/regulator unit, the entire specialized system dedicated to controls is not called the ships service air system. * **B) supply air system:** This is a generic, vague term that could refer to any system supplying air (including ventilation or forced draft systems). It is not the specific, industry-standard nomenclature for the instrumentation air network. * **D) forced draft air system:** This system involves large blowers (fans) used to push combustion air into a furnace or boiler to facilitate burning fuel. It operates at very high volumes and low pressures compared to compressed air systems and has a completely different function from powering pneumatic controllers.