Implementation of a new process, machine, or material triggers a qualification event for that change under the new H revision of IPC-J-Std-001.
When changing specific materials or cleaning solutions, one must determine and provide objective evidence that the improvement does not increase the risk of unused material or flux residues. Rather, it should improve the efficacy of removing the residues. The consequence of flux residues remaining on the PCBA may lead to electrochemical reactions that result in product failure while in use.