It would be difficult to answer your question definitively without know a great deal more about the number of employees, as well as your facility’s size and layout.
In general, I would say that a Wi-Fi-based real-time location system (RTLS) would be worth exploring. You likely already have a Wi-Fi system installed, but you would probably need to add a few access points in order to attain the required precision for real-time location monitoring. The downside would be that active tags are fairly expensive ($50 or so apiece), so if you have a lot of employees, this could prove to be an expensive proposition.
A passive system would offer less expensive tags, but you would likely need to install a high number of readers around a lot of doors in order to achieve accurate information regarding each person’s location within your facility. A passive system might work well if you needed only to know whether or not someone was in the building. Then you would only need to outfit the entrances and exits with RFID interrogators.
It would probably be best to engage a good systems integrator that has knowledge of both passive and active systems. That company could then recommend the best option, based on what you hope to achieve, the number of employees being tracked and many other factors.
—Mark Roberti, Founder and Editor, RFID Journal
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