The moisture in hot, humid, stagnant air surrounding a cold-water pipeline continually
diffuses to the cold surface where it condenses. The condensed water forms a liquid
film around the pipe, and then continuously drops off the pipe to the ground below.
At a distance of 10 cm from the surface of the surface of the pipe, the moisture content
of the air is constant. Close to the pipe, the moisture content of the air approaches the
vapor pressure of water evaluated at the temperature of the pipe.