#	Letters of Interpretation
1	04/22/1999 - 1910.111(b)(12)(ii) - Clarification of the requirement for an attendant during transfer of anhydrous ammonia.
2	01/31/1991 - 1910.111(b)(7)(iv) - Back-welding of threaded connections in anhydrous ammonia service.
3	10/29/1986 - 1910.111(b) - Requirements relative to the use of anhydrous ammonia in Diazo Reproduction machines.