PPM defect recording and comparison of defect rates between different sites is very important. A method of recording PPM rates, spread sheets and a training video on how to do is available. It was produced by the SMART Group and the Surface Mount Club in the UK a year ago. You can get a copy from the SMTA main office, just say Bob Willis sent you as I made the video. It will make a GREAT Christmas gift for all the staff. Just to put on record if you are seeing a 25 PPM defect level from a process that is not considered bad.