UL 142 Question (1993 vs. 2007)
UL 142 Question (1993 vs. 2007)
(OP)
The current UL 142 (2007) requires aboveground vertical single-wall tanks that are greater than 20,000 gallons to be constructed of 6-guage steel for the top 25-feet and 2-guage below that. Did the 1993 standard have the same requirement?




