RFID networks are subject to constraints derived from the interference caused by concurrent readers' operation. In this paper we discuss a general approach to decide whether a given system load produces stable operation, that is, if queue backlogs do not grow indefinitely. We assume that the RFID network operates in a time-slotted fashion, where traffic arrives as tag batches to RFID cells. The service rate (necessary to determine stability regions) of a RFID cell, given the batch size distribution and any arbitrary FSA policy is computed by simulation. This framework is illustrated with several examples.