Not to sound silly, but read the code, follow the code.
Different codes have different requirements, that's why it is not always possible to use a WPS qualified to one code with a different code.
In the case of D1.1 you do not have to determine the approximate volume of each weld bead. It is not a variable that must be tracked.
Al
I keep seeing references for clause 6 and PQR limits of 10% +- of average of passes, where in D1.5, clause 6, can I find that info?