The proposal would affect more than two million miles of gas distribution lines in the U.S. It was spurred by a fatal 2018 gas explosion in Massachusetts.
Construction unions hailed the new rule, but some contractor groups have strongly criticized it, with the Associated Builders and Contractors already planning a legal challenge.
Billions in aid from American Rescue Plan Act have had a major impact on the pension plans, which are used by tens of thousands of construction workers.