The importance of networking radiological protection equipment
03 February 2021
Arguably, there is no industry as highly regulated as the nuclear sector and none where mission-critical safety systems matter more. Here, Gary Bradshaw, Director of remote monitoring specialist Omniflex, explains how the nuclear sector can benefit by adopting new systems that save time and money while also improving plant safety.
Sellafield nuclear site in Cumbria, UK
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Friday March 11, 2011 may have begun like a normal day for workers at the Fukushima Daiichi nuclear power station in Japan, but it would turn out to be anything but normal. A nearby magnitude 9 earthquake set off a chain reaction of events culminating in a containment breach at the facility, which led to the evacuation of over 154,000 people.
The Fukushima Daiichi nuclear disaster is only the second in history to be classified as a level 7 event on the International Nuclear Event Scale (INES), the first being the Chernobyl incident. While the Kyshtym disaster of 1957 was worse in terms of radiation released, the INES ranks by impact on population and that incident only saw 10,000 people evacuated, much less than the 154,000 of Fukushima Daiichi or the 335,000 of Chernobyl.
While memories of the Chernobyl disaster may have faded for many, images of the exposed reactor of the Fukushima Daiichi plant raging out of control are still fresh in the minds of most. Nine years on, safety is still at the forefront of the agenda for the nuclear industry and all new systems and protocols for the sector must be developed with that in mind.
Commercial off-the-shelf (COTS) products are ready-made, packaged solutions that can then be adapted by the end user to meet their needs. These purchases are often alternatives to custom equipment and one-off developments. To date, the highly regulated environment in the nuclear sector has made many plant managers reluctant to adopt COTS products, even though they offer some key advantages.
Radiological monitoring systems
Every UK-based nuclear facility must follow strict guidelines for the radiological protection systems used to monitor the levels of alpha, beta and gamma radiation in the environment. Traditionally, this was done using non-networked wall-mounted radiation protection instruments. In the event of a high-level radiation alert or instrument failure, the monitor would detect and sound a local area alarm.
It isn’t only within buildings that radiation levels must be monitored, but the whole facility and potentially beyond. Perimeter monitoring systems, commonly known as emergency plume gamma monitoring systems (EPGMS) are a necessity to keep people safe in the event of a containment breach.
The primary function of EPGMS systems is to provide critical information to the emergency services in the event of a radiation leak. To that end, they are normally interfaced with meteorological systems since factors like wind speed and direction can determine if nearby populations are at risk of exposure.
Regulations set by the Health and Safety Executive (HSE) and the Office of Nuclear Regulators (ONR) have created demand for real-time and historical data monitoring and the creation of safe areas for operators to collect data without entering radioactive areas. To comply with these regulations, networking of radiological protection systems became standard practice.
However, networking the monitors increases the complexity of operations. Because traditional nuclear radiation monitoring systems are bespoke, the field of radiation protection instruments needs to be manually networked to a bespoke panel, requiring a skilled professional to spend days wiring and testing each bespoke 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. Again, this can take days to complete.
Furthermore, because the systems are often uniquely designed for a given job, nuclear facilities face significant challenges when it comes to maintenance of equipment. Since the bespoke panels aren’t standardised, maintenance work usually requires third party engineers to conduct a site visit to carry out repairs. This leads to much higher maintenance costs than if maintenance work could be handled in-house.
The question then becomes, what do you do when it isn’t feasible to use this bespoke method of installation, because of the time and financial burden it puts on a project? The answer comes in the form of a plug-and-play COTS product engineered to serve as the data collection point in a radiation monitoring network.
Case study – The National Nuclear Laboratory project
When the National Nuclear Laboratory (NNL) was tasked with installing 130 data collection points to connect large volumes of radiation protection instruments at Sellafield’s nuclear site, it was not feasible to use traditional methods. Efforts to overcome the challenges involved led to the development of the RPN1 COTS device.
Gary Bradshaw, Omniflex
The gateway device simplifies the task of gathering data from Ultra, Mirion, James Caunt Scientific and other manufacturers’ RS485-type radiation monitors. It then allows you to quickly read and store the data on radiological surveillance supervisory control and data acquisition (SCADA) systems.
Furthermore, it eliminates the need to run miles of power cables to each monitor in the field because it connects directly on a Fibre+Power ring network. Essentially, it takes its power from the facility’s secure mains supply via distributed power and network boxes located around the nuclear facility. It then uses hybrid power/fibre Ethernet data cables to deliver power to, and network, each subsequent RPN1 in a self-healing ethernet ring topology.
The RPN1 is a plug-and-play COTS device that was developed by Omniflex in collaboration with Steve Parkin, Senior Project Manager for NNL. It is standardised, being produced to ISO 9001 quality levels, which eliminates the need for additional third-party inspection during testing and installation.
“Commissioning a traditional system of this nature would have taken many multiples of the time and cost and would have been impossible to install without large outages across the facility,” explained Steve Parkin. “From a project perspective, the plug-and-play design significantly improved project reliability and lowered the installation risk. It also had the added benefit of drastically cutting working hours in active areas of the plant.
This project helped NNL save over £1 million in costs and ensured that the time spent by personnel in the active areas was greatly reduced. The units have since been used on other Sellafield buildings at the site and are specified to be used on new projects planned over the next five years.
If we are to avoid future disasters like Chernobyl and Fukushima Daiichi, the nuclear industry must continue to push the boundaries of what COTS systems can offer. By working with manufacturers, plant managers can benefit from innovative new technologies that meet industry demands. In the nuclear industry, where saving money and improving safety don’t often go together, new COTS systems are bringing the two together.
About the author:
Gary Bradshaw is Director at Omniflex, a global specialist in remote monitoring, protection and critical alarm systems. Having qualified as an engineer at GEC Switchgear, he went on to establish the Conlog brand in the UK and was later part of the management buyout by Omniflex in 1997. Over more than twenty years, Gary has grown the business from a start-up to a leading remote monitoring brand across many industrial sectors.
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