If the scratches are superficial and not exposing metal they are not rejectable. The bridging refers to exposing adjacent conductors because of a scratch down to metal. If there is soldermask still at the bottom of a scratch it is not rejectable. Sent from my iPhone > On Jun 10, 2018, at 9:07 PM, Willis Tam <[log in to unmask]> wrote: > > Hi All, > > Any comments and suggestion will be highly appreciated. > > B.R. > WT > > -----邮件原件----- > 发件人: TechNet [mailto:[log in to unmask]] 代表 Willis Tam > 发送时间: 2018年6月5日 10:23 > 收件人: [log in to unmask] > 主题: [TN] 答复: Interpretation of IPC standard for Solder Mask Scratches on PCBA > > > Hi Technet, > > > We have some arguments with one of our customers on the interpretation of IPC standard for Solder Mask Scratches on PCBA. > > According to IPC-A-610F §10.7.2. Solder Mask Coating-Voids, Blisters, Scratches. > Acceptable- Class 1,2,3. > Blister, Scratches, Voids that do not expose conductors and do not bridge adjacent conductors, conductor surface or create a hazardous condition which would allow loose mask particles to become enmeshed in moving parts or lodged between two electronically conductive mating surfaces. > > > Customer's product specification defined the PCBA to be compliance to IPC-A-610F standard Glass 3. > Customer found some scratches on solder mask surface on some of the PCBAs, the scratches are minor scratches, not deep/heavy scratches, not expose conductors(copper traces under solder mask), but go across the adjacent conductors; > We considered those scratches acceptable according to IPC-A-610F §10.7.2, but customer said not acceptable. > > The main argument is: customer considered any scratch which go across adjacent conductors as rejection, (Bridge adjacent conductors = go across), even not expose conductor. > This is an 5mil/5mil(width/space) board, not accept scratches which go across adjacent conductors means not accept scratch of 10mil (0.25mm) length. > > I would like to seek clarification from IPC guru so that we move forward > > > Best Regards > Willis Tam > > > >