ISO 6145-8:2005规定了一种使用扩散法制备含有10-9至10-3的组分摩尔分数的校准气体混合物的动态方法。通过使用该方法可以实现通过将相对组合标准不确定度乘以不大于±2％的覆盖系数k = 2获得的相对扩大的测量不确定性U。 通过保持扩散源和使用地点之间的路径尽可能短，该方法可以应用于在室温下产生液体的有机组分的低浓度校准气体，沸点范围为约40° C至160°C。 ISO 6145-8:2005不仅适用于在环境和室内空气浓度水平下生成广泛的碳氢化合物的校准气体混合物，而且适用于生成低浓度的水混合气体

ISO 6145-8:2005 specifies a dynamic method using diffusion for the preparation of calibration gas mixtures containing component mole fractions ranging from 10-9 to 10-3. A relative expanded uncertainty of measurement, U, obtained by multiplying the relative combined standard uncertainty by a coverage factor k = 2, of not greater than ± 2 % can be achieved by using this method. By keeping the path between the diffusion source and place of use as short as possible, the method can be applied for the generation of low-concentration calibration gases of organic components that are liquid at room temperature, with boiling points ranging from about 40 °C to 160 °C. ISO 6145-8:2005 is applicable not only for the generation of calibration gas mixtures of a wide range of hydrocarbons at ambient and indoor air concentration levels, but also for the generation of low-concentration gas mixtures of water.