UL-391 Complete Document History
Standard for Solid-Fuel and Combination-Fuel Central and Supplementary Furnaces

Complete Current Edition:
   5TH EDITION - Solid-Fuel and Combination-Fuel Central and Supplementary Fu - Sept. 10, 2010
   CHANGE 09/13 - REVISION CHANGE - CODE B - Sept. 17, 2013
   CHANGE 06/14 - REVISION CHANGE - CODE B - June 12, 2014
   CHANGE 08/19 - REVISION CHANGE - CODE B - Aug. 28, 2019

Obsolete Revision Information:
   CHANGE 03/10 - REVISION CHANGE - CODE A - March 31, 2010
   CHANGE 01/10 - REVISION CHANGE - CODE A - Jan. 27, 2010
   CHANGE 12/09 - REVISION CHANGE - CODE A - Dec. 3, 2009
   4TH EDITION - Solid-Fuel and Combination-Fuel Central and Supplementary Fu - Oct. 20, 2006
   3RD EDITION - Solid-Fuel and Combination-Fuel Central and Supplementary Fu - April 13, 1995
   1991 EDITION - Solid-Fuel and Combination-Fuel Central and Supplementary Fu - Jan. 1, 1991