Discharge of the air inlet for a regulator should be directed in which orientation relative to the inlet and at what distance?

• A. facing up 10 ft away from inlet
• B. facing down 5 ft away from inlet
• C. perpendicular to inlet, 10 ft away
• D. facing down 10 ft away from inlet

Answer: (D)

Discharge from a regulator is exhaust air that can carry oil mist or condensate, so it must be directed away from the inlet and kept clear of the intake to prevent re-ingestion and nuisance to people nearby. Pointing it downward and placing it about 10 ft from the inlet ensures the exhaust is directed to the floor and far enough away to avoid being drawn back into the inlet or into surrounding equipment. Directing the discharge upward or too close to the inlet increases the risk of re-entry of exhaust, while a sideways (perpendicular) direction at the same distance does not guarantee the exhaust won’t interact with the inlet or nearby components. Hence, facing down 10 ft away is the safest and most effective arrangement.