If a welder is going to weld rebar to a structural beam or column and the specification is to D1.1; dose the welder need to be rebar certified to D1.4 to weld or may a welder certified to D1.1 weld the rebar to the beam.
Per my response to your other post in the Technical section, I feel D1.1 applies to rebar/structural joints. Rebar/rebar joints would be D1.4. Chet Guilford
The welder must be certified to D1.1 for the structural steel component and D1.4 for the rebar. They must be certified to both codes. This is the first page of the D1.4.