Liquid Being Drawn from Above the Liquid Level: This will occur if a pipe leaving the tank has a penetration set above the liquid level in the tank, and the pipe has a fluid zone that is liquid.

Vapor Leaving below the Liquid Level: This will occur if a pipe leaving the tank has a penetration set below the liquid level in the tank, and the pipe has a fluid zone that is vapor.

Vapor Entering below the Liquid Level: This will occur if a pipe entering the tank has a penetration set below the liquid level in the tank, and the pipe has a fluid zone that is vapor.