Testing the Pulse of Hospital 5G – Oulu Researchers Put Safety First
A research team at the University of Oulu is systematically testing how private 5G networks perform in hospitals. Their focus is on safety, signal reliability, and the resilience of critical healthcare services.
At a Hola 5G Oulu event, Assistant Professor Erkki Harjula detailed the work being done to evaluate 5G deployment in clinical settings. Harjula is researching for the University of Oulu’s 6G Flagship and 6GESS programmes and leads a wireless architecture team within the university’s Centre for Wireless Communications, where they focus on secure and functional wireless systems for healthcare.
Although 5G is already used in many sectors, its introduction into hospital environments has raised understandable concerns among healthcare workers. Are the signals safe? Could they interfere with life-saving equipment? And what happens when the network is disrupted?
Harjula’s team designed a battery of tests to answer those questions. Mohsin Khan, supervised by Matti Hämäläinen, began by studying the local radio environment in both the old and new hospital buildings. The aim was to understand what frequencies were already in use, and whether introducing a 5G signal would add noise or interference.
One early finding was reassuring: modern surgical theatres, shielded with lead panelling, naturally block out most external signals. The 5G signal, once active, remained clearly within its designated frequency band and did not encroach on those used by medical devices, Wi-Fi or Bluetooth.
The researchers then measured signal strength to assess safety. Their readings confirmed that the 5G emissions in the hospital stayed well below international exposure limits. “We’re operating in the non-ionising radiofrequency range, so there’s no cause for concern,” Harjula said, adding, “the signal intensity doesn’t even come close to the limit values.”
Beyond safety, the team, including Shakthi Hingurala and Ijaz Ahmad, ran a series of functional stress tests. These included streaming ultra-high-definition video from multiple devices simultaneously and measuring how the network handled mobility between hospital zones. Even under heavy load, the private 5G network maintained stable connections and high performance.
The tests aren’t yet complete. A second phase, currently underway, is designed to simulate disruptions. The team decided to add this stage, although it wasn’t in the original project plan, to investigate further how the network reacts and recovers. Harjula described deliberately disabling base stations and injecting cyberattacks to observe this. These results, expected later this spring, will inform final recommendations.
One of the most promising directions emerging from the study is the use of edge computing—placing key data and services inside the hospital network, rather than relying on distant cloud servers. “If there’s an internet outage, cloud-based services fail. But with edge computing, critical hospital functions can keep running, even though the main parts of the service are located in a cloud data centre,” Harjula explained.
Edge architecture also improves data security. Hospitals can decide which information stays on-site and what gets transmitted externally, giving them more control over patient confidentiality.
Harjula acknowledges that this initial testing phase focused on verifying the basics: performance, safety, and interoperability. The next step is scaling. As hospitals adopt more connected devices, the systems must be optimised for complex, hospital-wide use. This involves, e.g. AI-driven decision-making such as identifying the most critical services or their parts, determining their operational tier placement, and planning for seamless service adaptation and other types of mitigation during and after disruptions.
This research feeds directly into that future. It also provides evidence-based information for decision-makers evaluating the risks and benefits of 5G in healthcare.
“Our job is to make sure the network does what it promises,” Harjula says. “Not just when everything goes smoothly—but especially when things go wrong.”
See Erkki Harjula’s presentation, 5G Network Security: Testing for Safe and Smooth Deployment. The presentation given in Finnish has subtitles in many languages.