We are looking at an accountability solution for a very large site with 6,500 employees, using semi-active tags and possibly Wi-Fi. How can we account for individuals travelling in motor vehicles onto the site?
People don't always put their name tags on first thing in the morning, so to ensure that you can identify people arriving at and leaving a site, there are two options.
One option is to place a passive ultrahigh-frequency (UHF) RFID sticker on the windshield of each car and associate that number, along with the battery-assisted personnel tag's ID number, to the same individual. You will need to install an RFID-enabled gate at the parking lot's entrance. When someone arrives at the site, the reader at the gate interrogates the windshield tag and opens the gate, provided that the person is a legitimate employee. The time of arrival and ID number are recorded, so you will know that worker has arrived. The same can be done at the parking lot's exit.
If you do not wish to purchase 6,500 additional tags for the windshield, another option would be to require each employee to hold up his or her battery-assisted personnel tag so that the gate reader can capture its ID. The downside is that if a person has tossed his or her badge into a briefcase, cars will be held up while he or she looks for it, and if a worker has forgotten the badge at home, someone else will need to run out to the gate, identify that individual and use his or her own badge to let that person in.
—Mark Roberti, Founder and Editor, RFID Journal