The present invention is directed to a method for preparing a nanofiber web by feeding a polymer solution, which has at least one polymer dissolved in at least one flammable solvent to a spinning nozzle, discharging the polymer solution from the spinning nozzle into a blowing gas or gas mixture that will not support combustion, wherein the blowing gas exits a jet at a lower end of the spinning nozzle, to form polymer nanofibers and collecting the polymer nanofibers on a collector under the spinning nozzle, wherein an applied high voltage differential is maintained between the spinneret and the collector.