Over a long period of time it has been recognised that there is a need for a greater understanding of the airflow around and into aerosol samplers. In particular, an accurate description of the region on the sampler surface within which all the flow enters the sampling inlet, is vital in describing a samplers performance. In this work a theoretical study is made of the size of this region for a spherical bluff body with suction. Analytical expressions derived previously, describing the size of the region as the orientation of the suction inlet with the freestream varies, are extended to cover small angles of orientation.