Cynthia, 3 dB is a good margin to stick with. You sometimes have to pass products which are under, but you know in your heart of hearts that some of them are going to come off the line or find their ways into substandard boxes and end up at or over the limit.
Here's another thought. Whether a product is at the limit also depends upon the way in which you make the specified measurement--QP vs. average, for example. Regards, Brad Rehm Professional Testing Round Rock, TX
