JinSee Goh: - In response to your question about how many lifted pads and open traces are allowed for repair within a printed circuit board. The answer to the question is "who cares" and obviously the answer to that question is that your customer cares. So, as Jeff Ferry noted, have a conversation with the customer and find out what he will accept. As far as I know there are NO standards or specifications that place limits on how many times a circuit board can be repaired. - Your question raises some additional questions that may shed some light on how to arrive at an answer. Q1 Is the circuit board being "repaired" after field failure or is it a newly manufactured product with defects that need to be "repaired"? Q2 Is this a multilayer board or a double sided board. Q3 You asked "within a printed circuit board". Does that mean that the defects are on internal layers of the circuit board, or are the defects on the surface (top or bottom). Q4 Are your people trained and/or certified to do repairs of that nature and are the repairs performed in accordance with a documented procedure or process? Q5 Does your customer have the right to review/approve your repair procedure/process, and if-so, has he done so. - If the answer to Q1 is that it is a newly manufactured assembly, then you need to both look at the assembly processes/procedures to assure that damage is not being inflicted during assembly and also look upstream to the pwb supplier. If is a newly manufactured assembly then negotiate with the customer about how many "repairs" (if any) he is willing to accept. If the assembly is being returned for repair after failure in field service, then your organization needs to closely review the repair techniques used and define the maximum number of repairs that you feel can be performed before the reliability of the assembly is reduced to an unacceptable level. - Note that in the distant past (when the electronics assembly world was influenced by Mil-Stds.) there was a generally accepted limit of five (5) as the number of times that any individual connection could be reworked or repaired. The limit of five times was (and is) based on a gross misunderstanding and misapplication (that I won't go into here) of the Mil-Std. that controlled pwb assembly (Mil-P-55110). Note also that the military organizations spent a lot of time and money training and certifying their people to perform those repairs with documented procedures under closely controlled conditions. - Hope that the above helps. If additional questions come up please contact me off line. Regards, Jim Moffitt, Moffitt Consulting Service, 317/773-5570