泄漏等级的选择不限于阀门设计，但建议使用各种商用设计和密封材料类型的阀门。FCI 91-2-2018不能用作预测非规定条件下阀座泄漏的依据。本标准不适用于通常用于高真空和超高真空（10-3托或更高）的阀门。本标准无意排除 任何试验方法和/或流体，只要结果与本标准表1相关。

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.FCI 91-2-2018 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.