Selection of a leakage class is not restricted as to valve design but valves of various commercially available designs and types of sealing materials are suggested.This standard cannot be used as a basis for predicting seat leakage at conditions other than those specified.This standard does not apply to valves normally used on high and ultra high vacuum (10-3 Torr or higher).This standard is not intended to preclude
any test method and/or fluid so long as results can be related to Table 1 of this standard.