Evidencia Thermassure RFID tags have some unique features not offered by conventional temperature loggers. The tags store a 96bit ePC code for logistics, and high-accuracy temperatures with a standard, but expandable, 4,000 reading capacity and accuracy of better than 0.3°C.
These are passive RFID devices and are approved by the FAA for use in aircraft and the FDA for food and pharmaceutical applications. Data can be downloaded any number of times during a mission, and details of the date, time and reader serial number are stored. Furthermore, the data can be read with very short download times, through packaging and even gel cooling packs, using remote RF readers of USB PC readers.
Temperature ranges from –40°C to 70°C or –80°C to 150°C with external probes can be measured, and all versions are fully immersible to IP67. They have LEDs to indicate function and alarm status.
Prices are extremely low for high-volume usage. Tag types include single-use and multi-use versions as well as loggers and trackers. Loggers store temperatures and other data with day, date and time, so the output can be a time temperature graph. Trackers store only the number of minutes spent within defined temperature ranges, and so generate a temperature histogram. This provides all the data needed to assess product quality; for example, exactly how many minutes spent and what temperatures in an out of specification situation. Safety or available shelf life can then be reliably assessed.
The tags are extremely compact and light, and can be mounted inside a carton to maintain its tamper-proof status, while data can be downloaded with a reader. If visible feedback of alarm status or deep core temperatures are required, the external probe tags can be slipped into a document holder stuck to a carton, and the sensor embedded in the contents. The cartons can still be stacked – the loggers are so thin and rugged.
