定义用于评估工作场所和周围环境中空气中颗粒物可能对健康造成的影响的粒度分数的采样约定。定义可吸入、胸部和呼吸部分的约定；胸外和气管支气管常规可根据定义的常规计算。这些约定不应与其他术语中定义的限值结合使用，例如根据长度和直径定义的纤维限值。

Defines sampling conventions for particle size fractions for use in assessing possible health effects of airborne particles in the workplace and ambient environment. Defines conventions for the inhalable, thoracic and respirable fractions; extrathoracic and tracheobronchial conventions may be calculated from the defined conventions. The conventions should not be used in association with limit values defined in other terms, for example for limit values of fibres defined in terms of their length and diameter.