Reality capture workflows raise the bar for safety in nuclear decommissioning

Founded in 2019 as a service unit of Fortum, eSite is an industrial Virtual Reality solution provider who are no strangers to complex environments of plants, factories and construction sites. For example Fortum Nuclear Services is using eSite in the first nuclear decommissioning project in Finland, decommissioning of the FiR 1 nuclear research reactor. Working safely in the nuclear industry is a key concern, for obvious reasons, and nuclear safety in Finland has been improved continuously for more than 40 years.

By creating realistic 3D point cloud models from reality capture of areas due to be decommissioned next, an extra layer of safety can be created. Because the time spent by field operators performing decommissioning tasks at the field needs to be minimized, it is paramount that the work procedures they follow are both efficient and correct – something that can have an increased likelihood to succeed if rehearsed in virtual reality created through reality capture, says Miko Olkkonen, head of eSite.

“Having a room or an area that needs to be decommissioned in a nuclear plant means that you need to go in there, cut some pipes that once had radioactive water, and you need to do it safely. This also means that you need to do everything to make it as fast as possible and as safe as possible with the lowest radiation dose.”

When planning the work procedures virtually it is possible to refine them to be completed quickly and accurately, avoiding radiation hot spots. Every action taken in the controlled area of the facility means time spent being exposed to radiation. The principle, “as low as reasonably achievable” drives each of these choices. When combined with other sensors that can also map radiation, an overlay of radiation hotspots can be augmented into the visualizations – helping to identify risky areas ahead of time.

“We can do the reality capture in the morning, process it for the afternoon, put the scan into virtual reality glasses, and the field operators can practice the work they need to do for a 15 minute cut of the pipe. In virtual reality, you can practice where you walk, what you do, where you keep your equipment. You can practice to do to it faster, with fewer steps, avoiding hot spots. Of course the environment changes during the decommissioning and the advantage is that you can discard the initial reality capture, and the next time you need to perform work in that location you take a new reality capture of that moment,” says Olkkonen.

Inside Finnish nuclear power plants, where Fortum Nuclear Services and eSite operate, there are radioactive areas and rooms that are accessible to people only for few days per year during the nuclear power plant’s annual outage. During these few days, hundreds of maintenance tasks are performed with a minute accurate schedule.

The best practice for a decade has been to go in to these areas and perform stationary laser scanning. This has enabled planning for next year’s outage tasks during the operating phase of the plant, though the areas are not physically accessible. Even with 10’s of hours of scanning work, we have been able to capture only limited sections.