IFCA and the Illinois Department of Agriculture are asking for our members' help in assuring that air is not introduced into anhydrous ammonia nurse tanks.  The introduction of air into nurse tanks at the ag retail facility or at the farm field is not allowed by the IDA.  Air can lead to stress corrosion in the nurse tanks and since ammonia is a closed transfer system, air can have detrimental impacts on the entire ammonia distribution system including in storage tanks and transport tanks.  Please make your employees aware of this and please also advise your farmer customers that this practice is not allowed in Illinois in order to assure the integrity and safety of anhydrous ammonia equipment.