Tackling PCB cleanliness is a tough job; residues on printed circuit boards are directly related to the reliability of the produced hardware and can result in serious failures if not known or monitored. But how do you measure "cleanliness"? How clean is "clean"? The IPC-5701 provides guidance into how these issues should be approached and specified in purchasing documents, addressing levels of cleanliness, how to specify them, common locations for testing, and information on sample sizes. 6 pages. Released July 2003.