A guard tour patrol system is a system for logging the rounds of employees in a variety of situations such as security guards patrolling property, technicians monitoring climate-controlled environments, and correctional officers checking prisoner living areas. It helps ensure that the employee makes his or her appointed rounds at the correct intervals and can offer a record for legal or insurance reasons. Such systems have existed for many years using mechanical watchclock-based systems (watchman clocks/guard tour clocks/patrol clocks). Computerized systems were first introduced in Europe in the early 1980s, and in North America in 1986. Modern systems are based on handheld data loggers and RFID sensors. The system provides a means to record the time when the employee reaches certain points on their tour. Checkpoints or watchstations are commonly placed at the extreme ends of the tour route and at critical points such as vaults, specimen refrigerators, vital equipment, and access points. Some systems are set so that the interval between stations is timed so if the employee fails to reach each point within a set time, other staff are dispatched to ensure the employee’s well-being. An example of a modern set-up might work as follows: The employee carries a portable electronic sensor (PES) or electronic data collector which is activated at each checkpoint. Checkpoints can consist of iButton semiconductors, magnetic strips, proximity microchips such as RFIDs or NFC- or optical barcodes. The data collector stores the serial number of the checkpoint with the date and time. Later, the information is downloaded from the collector into a computer where the checkpoint’s serial number will have an assigned location (i.e. North Perimeter Fence, Cell Number 1, etc.). Data collectors can also be programmed to ignore duplicate checkpoint activations that occur sequentially or within a certain time period. Computer software used to compile the data from the collector can print out summaries that pinpoint missed checkpoints or patrols without the operator having to review all the data collected. Because devices can be subject to misuse, some have built-in microwave, g-force, and voltage detection.