Research of sampling and testing rates for project tests listed in the Guide Schedule shows that the risk of either rejecting "good" material or accepting "bad" material ranges from 20 percent to 40 percent. Use this baseline for sampling and testing. Increase the frequency of testing for high-variability materials and when testing results do not meet specifications

Current Guide

• May 2016

Previous Guides

• March 2015
• August 2010
• November 2007
• April 2005