Dear friends,
I'm trying to find a common value for the maximum defect rate to be acceptable in pipe spool fabrication among welders. I would appriceate if anyone has an experience to share or lead me to a standard.
As we all know the defect percentage in general will differ according to the welding processes, but I need to know manual welding as GTAW or SMAW acceptable defect rate, which should be higher than a rotated pipe welded by a machine in flat position.
I'm not sure which rate is the best to see the total situtation in the shop and individually among welders.

defected joint / total radiographed joints? 2%? 3% ?
defected length / total radiographed? 0.5%?
defected RT shots / total RT shots? ????

Thanks