A process for reducing corrosion in a gas distribution network of ultra high purity gas or any part of said distribution network, including: (a) Wet cleaning the gas distribution network or at least one part thereof with a wet cleaning agent, (b) Liquid drying the gas distribution network or the at least one part thereof with an H.sub.2 O desorbing liquid drying agent selected from the group consisting of acetone dimethylacetal DMP, 2.2 dichloropropane DCP or 2.2 dibromopropane DBP, mixtures thereof and any equivalent thereof, (c) purging said gas distribution network or any part thereof with a dry high purity gas comprising less than 1 ppm of any impurity, and (d) evacuating the gas distribution network or any part thereof at a pressure which is lower than 5.times.10.sup.4 Pascal (e) exposing the gas distribution network or any part thereof to an atmosphere including an ultra high purity corrosive gas or air.