The Qinshan Nuclear Power Plant, part of the China National Nuclear Corp. , has deployed a system that employs passive ultrahigh-frequency (UHF) RFID tags and readers to identify the locations of thousands of workers, according to zone, as well as help locate individuals in the event of an emergency and prevent anyone from entering unauthorized areas. Since installing the solution last year, the company has also been able to use it to verify workers’ hours, according to Sun International, the system’s provider.
Qinshan, located approximately 100 kilometers (62.1 miles) southwest of Shanghai, is one of the largest nuclear power plants in the world, with nine reactors spread across a 10-square-kilometer (3.9-square-mile) area. On a typical day, about 7,000 workers and contractors are onsite at any given time.
Chinese regulations, dictated by the National Nuclear Safety Administration (NNSA), require that nuclear facilities be able to monitor the locations of individuals at their site during an evacuation. This typically has been accomplished using a manual paper-and-pen process. Hundreds of workers serve as emergency managers, each assigned to oversee a particular assembly point. At each assembly point, area workers gather to be accounted for and escorted off the premises aboard buses. The emergency manager writes down each individual’s name, or checks it off a list. This process is slow, however, and vulnerable to errors since it doesn’t list anyone who might have come onsite that day but failed to report to the assembly point.
Sun International, a Georgia-based company with offices in Washington, D.C., and Wuxi, China, was founded 20 years ago to provide telecommunications-related software, but in 2009 it introduced radio frequency identification technology to its solutions. The firm was especially focused on smart nuclear power plant solutions, says Yaojun Sun, Sun International’s founder and CEO.
The company researched and developed the solution for several years in-house, before conducting some testing at the Qinshan Nuclear Power Plant in mid-2013. The site has four separate power plants, and the system was permanently deployed at one of those locations in October 2014, and has since been expanded to all four plants.
Every plant contains four to five zones, each measuring up to 1 square kilometer (0.39 mile) in size. For the initial deployment within the first plant, Sun International installed 30 Impinj R420 readers at key locations, such as zone entrances and emergency areas, as well as 100 antennas to ensure that tag ID numbers were captured.
In designing the system, Sun International knew that if workers were issued RFID badges made with passive UHF tags, reading those tags would pose several challenges: For example, large numbers of people could pass a reader simultaneously, and each person’s tag would need to be interrogated, even if the RF transmission was obstructed by other individuals. In addition, Qinshan needed to read the tags of those not only on foot but in vehicles, since staff members are escorted off the premises in buses during an evacuation. Therefore, Sun International needed the system to be able to read tags inside a moving vehicle.
Although the company tested multiple tags, Sun reports, none provided the read sensitivity required for the application, so the firm opted to develop its own specialized tag that could be interrogated in a crowd or through a bus window. That tag is being made for Sun International by a third-party provider.
Qinshan now has more than 100 readers installed throughout the entire plant. Sun International also provided its software to store and manage read data, as well as display location data of individuals on a map of the facility.
With the system, every employee is issued an RFID badge with the Sun International UHF tag built into it. Each worker wears that tag around his or her neck on a lanyard, along with that person’s existing photo ID badge. Sun says his company investigated the possibility of embedding the RFID tag in the existing badge, but found that the transmission distance was not as long, or as effective. So each staff member now wears both the RFID badge and the original ID badge.
The Sun International software stores each worker’s tag ID number, name and job title, as well as the zones in which that individual is permitted to enter. One or more readers at a zone’s entrance gate capture each employee’s ID, indicating that person has arrived, and that data is then stored in the Sun International system.
Contractors who arrive onsite for the day provide their own information, such as their name and employer company, to the plant’s staff. The workers enter that data into the facility’s system, and each visitor is then provided with a temporary badge with a built-in RFID tag, linked to that contractor’s identity.
As individuals move around the facility, they pass RFID readers, at which time their tag IDs are again captured, indicating where those individuals were last located. Security guards at the plant can view this data in real time on their computer screens, and thereby view an alert in the event that an individual has entered an unauthorized area. They can also receive a text message if they opt for that function, and send personnel to that area to resolve the problem.
If an emergency occurs, workers and contractors proceed to the nearest assembly point, where a manager is posted to identify who has arrived and provide instructions about their next step. They can be escorted out of the facility or to another area, or they can soon return to their work if it was just a drill or false alarm.
As individuals make their way to the bus and then out of the facility in that vehicle, readers along the exit route capture each movement, at a range of up to 10 to 15 meters (32.8 to 49 feet), even in the moving bus. The software is then updated to reflect that data.
Staff members in the security department can view who is within a particular zone by looking at the map. For each zone, a number is displayed indicating how many people are present. Security management can click on that number and view a list of the names of those still in the zone, based on reads of their RFID tags.
The RFID system has provided several benefits, which Qinshan described in a written document that Sun International submitted to the China Nuclear Energy Association in order to earn certification for that deployment. In the document, Qinshan indicated that the solution provides real-time location information for workers and their vehicles onsite. “The system has completely revolutionized the whole processes from error-prone manually counting method to automatically collect and visualize on a computer screen in real time,” Qinshan wrote. “The system has passed very rigid testing and shown very satisfactory results in many emergency drill since last October.”
In addition, Sun says, the plant has found another purpose for the technology, in that the system serves to reinforce employees’ time-card records. If an individual has an unusual hourly work report, for instance, the company’s managers can access the RFID system and confirm that he or she actually worked those hours. They can also determine if any employees frequently arrive late or leave their shift early.
In the meantime, the technology’s emergency functionality is regularly put to the test. “Since it went live, they have conducted many drills,” Sun states, “and they’ve had unbelievable results.” The system proved to collect tag reads of each worker at a rate close to 100 percent, he reports.
Sun International is installing the solution, known as the Nuclear Power Plant Automated Emergency People Management System, at several other Chinese nuclear power plants, and is currently in discussions with a number of U.S.-based nuclear plants as well. According to Sun, the solution will also be marketed for use in other industries, such as mining and petroleum.