Which statement correctly describes a sweep purge?

Which statement correctly describes a sweep purge?

• A. There is a continuous flow of inert gas through the vessel
• B. There is a continuous flow of air through the vessel
• C. The purge uses vacuum only
• D. The vessel is purged with steam

Answer: (A)

Sweep purge relies on flushing the vessel with an inert gas, like nitrogen, to push out flammable vapors and reduce the oxygen level so ignition is unlikely. The continuous flow is essential because it constantly replaces the interior air with inert gas, carrying vapors out and preventing air from re-entering and reintroducing oxygen. That makes this description the best fit. Using air would bring oxygen and increase ignition risk, relying on vacuum alone doesn’t maintain an inert environment, and steam would introduce heat and moisture rather than creating a safe, inert atmosphere.

Sweep purge relies on flushing the vessel with an inert gas, like nitrogen, to push out flammable vapors and reduce the oxygen level so ignition is unlikely. The continuous flow is essential because it constantly replaces the interior air with inert gas, carrying vapors out and preventing air from re-entering and reintroducing oxygen. That makes this description the best fit. Using air would bring oxygen and increase ignition risk, relying on vacuum alone doesn’t maintain an inert environment, and steam would introduce heat and moisture rather than creating a safe, inert atmosphere.