Question

Identify the WRONG statement: The application of controlled air recirculation in an underground work place can

• A. increase the air velocity at the work place
• B. lead to increased concentration of contaminants in the work place
• C. require the installation of an additional fan in the system
• D. lead to overall ventilation cost savings

Hint:

Air recirculation does not inherently increase contaminants—proper filtering and monitoring ensure safe levels.

Answer 1

The Correct Option is B

Controlled air recirculation reuses a portion of the ventilated air in underground mines to reduce energy consumption. Step 1: Evaluate impacts of air recirculation. - It increases airflow velocity because additional air paths are established → (A) is correct. - It improves efficiency but does not necessarily increase contaminants if properly filtered; the system is designed to maintain safe contaminant levels → (B) is the WRONG statement. - Some systems require additional booster fans → (C) is correct. - Recirculation reduces power consumption by reducing the volume of fresh air needed → (D) is correct. Thus, the incorrect (wrong) statement is (B).
Final Answer: (B)