本航空航天推荐规程（ARP）的范围包括在何处、何时以及多久对航空航天车辆上的液压系统流体进行采样，以进行颗粒污染测量。由于液压设备可靠性的重要性，液压流体颗粒污染的测量受到航空航天界的关注。系统油液中始终存在污染，即使是新的未使用的油液。污染水平必须低于不会对系统运行产生不利影响的水平。本ARP借鉴了航空航天行业的经验和实践，为航空航天飞行器液压系统中的流体污染取样建议建立了标准。然后，可以对流体样品进行颗粒污染物和其他有害污染物（如氯化溶剂和水）的测量。

The scope of this Aerospace Recommended Practice (ARP) covers where, when, and how often to sample hydraulic system fluid on aerospace vehicles for particulate contamination measurements. The measurement of hydraulic fluid particulate contamination is of concern to the aerospace community because of the critical importance of hydraulic equipment reliability. Contamination is always present in the system fluid, even in new unused fluid. Contamination must be below a level that will not adversely affect system operation. This ARP draws from aerospace industry experience and practice to establish criteria for fluid contamination sampling recommendations in aerospace vehicle hydraulic systems. Fluid samples can then be subjected to measurement of particulate contamination and of other harmful contaminants such as chlorinated solvents and water.