This International Standard defines a minimum application protocol to support sensors and the monitoring of batteries in conjunction with RFID tags utilizing the air interface as defined in the ISO/IEC 18000 series. This application protocol for sensors applies to RFID tags irrespective of their operating frequency. This application protocol is agnostic to how the sensor(s) are connected to or integrated within the RFID tag; however, the communication between the interrogator and the sensor(s) is always through the RFID tag. This will allow the interrogator and application to understand a compliant sensor's characteristics and process its information without prior knowledge of that sensor. This will allow sensors to announce their sense activity and the units of measurement to the interrogator. This International Standard provides common encoding rules for identifying sensors, their functions, and their delivered measurements. It also defines the process rules to support the following functions: — selecting and de-selecting a particular sensory function when more than one is supported by the RFID tag; NOTE The measurement of time or battery life can be considered as separate sensory functions. — setting sensor parameters both initially and ongoing; — starting and stopping the monitoring function of a sensor; — accessing sensor data; and — carrying out basic processing of sensor data and interpreting this into a format that is meaningful for an application.