- Hi All whats the latest regarding Vapour Management columns take off points. At present I have a 2" to 3/4" T on the column at the take off point going directly to a 3/4" ball valve then 3/4" elbow with 8" drop to liebeg which is 1/2" within 3/4" x 30" long. How does this compare to anyone elses set up. Is it good, bad or standard. Any comments much appreciated.