Simplifying radiological monitoring

TRADITIONALLY, CONSUMERS BUY COMMERCIAL OFF-the-shelf (COTS) equipment but niche markets have used bespoke equipment.

Commercial products are ready-made and packaged solutions bought as they are and possibly adapted by the end user to meet their needs. These purchases can be an alternative to custom equipment and one-off development.

In the nuclear industry, where tight regulation, mission- critical safety systems and high levels of complexity are the norm, it’s easy to see why commercial equipment is usually overlooked in favour of custom-made bespoke equipment.

Now, however, there are examples of commercial products that can be used, such as those for gathering data other manufacturers’ radiation monitors and allowing the user to read and store data on radiological surveillance SCADA systems very quickly.

All nuclear facilities must adhere to strict guidelines for the radiological monitoring systems used to monitor the levels of alpha, beta and gamma radiation in the air.

In the UK, meeting regulations set by the Health and Safety Executive (HSE) and the Office for Nuclear Regulation (ONR), has created demand for real-time and historical data monitoring. Safe areas have been created allowing operators to collect data without entering radioactive areas. To do this, networking radiological monitors became the industry standard — but that adds a layer of complexity.

Because traditional nuclear radiation monitoring systems are bespoke, each has to be manually networked to a bespoke panel, requiring a skilled professional to spend days wiring and testing each unit. Each of these must then be inspected by an external engineer from a regulating authority to check for human errors, before it can be certified for use. This, again, can take days to complete.

What if this method of installation, is too slow and expensive? One answer is the Omniflex Radio Protection Node 1 (RPN1); a commercial product that can serve as the data collection point in a radiation monitoring network.

The RPN1 Gateway

The RPN1 is a gateway device, developed to simplify the process of data collection from a variety of radiation protection devices from different manufacturers. It uses their RS485 communications ports and connects them to the plant’s standalone radiological surveillance SCADA system.

The RPN1 eliminates the need to run miles of expensive power cables to each monitor. The device takes its power directly from the facility’s secure mains supply, via distributed power and network interface boxes around the nuclear facility. It then uses hybrid power/fibre Ethernet data cables to power and network each RPN1 in a self- healing ethernet ring topology. This allows the network to maintain uptime and data integrity in the event of any RPN1 or single network failure.

The RPN1 device can be installed in minutes and eliminates thousands of man hours of work. It meets ISO 9001 quality levels, so there is no need for additional third-party inspections during the installation and testing of the system.

“The commission of a traditional system would have taken many multiples of the time and cost and would have been impossible to install without large outages across the facility,” explains Steve Parkin senior project manager for National Nuclear Laboratory (NNL) who helped to develop the device. “From a project perspective, the plug-and-play design significantly improved project reliability and lowered the installation risk.”

“The small footprint of the RPN1, compared to the large panels that are normally required to meet standards, meant we could overlay the system into the ageing facility without the need for expensive repositioning of adjacent equipment. This approach allowed us to perform factory tests offsite as a complete system, eliminating 90 per cent of the commissioning required on site in active areas,” Parkin adds.

The RPN1 device has helped NNL save over £1 million in project costs since it was first deployed, with units in use on the Sellafield site, and specified for deployment on new projects planned in the next five years.

Memory sticks, batteries and other consumables offer examples of consumer products that do not translate well into business purchasing, because they become obsolete too quickly. But bespoke is not always best for every application, as the RPN1 illustrates.

Commercial off-the-shelf products have a place in an industry as highly regulated and complex as the nuclear sector. By being open-minded and willing to explore diverse applications of technology, plant managers can use them to meet the cost and time requirements of even the most demanding sectors.

Author information: Gary Bradshaw is Director of Omniflex