The guidelines specify a number of different categories of rDNA/sNA molecules. One of the most important categories is the Exempt category. Experiments that qualify for this category do not need approval by the Stanford University Institutional Biosafety Committee (the Administrative Panel on Biosafety [APB], see Chapter 5). To determine if your experiments are exempt, you can check Section III, Category F in the NIH Guidelines (online); a short reference guide is presented in Table 1 and 2.