In response to concerns that raised EMF (Electromagnetic Field) levels could pose a risk to life sustaining hospital equipment, Ramboll conducted a study at the University Hospital in Aarhus Denmark to determine if the EMF levels exceeded recommended levels.
The study examined the overall effect of the combined EMF levels from cell phones, DAS facilities (Distributed Antenna System), DECT (Digital Enhanced Cordless Telecommunications) and emergency service TETRA radio (Terrestrial Trunked Radio). The study was carried out at several locations in the hospital. Previous coverage measurements provided the transmit-power-levels for cell-phones, from which the maximum EMF was calculated.
In order to lower the EMF from cell phones, the hospital had already installed DAS facilities. Furthermore, most of the medical staff already used smart phones with an emergency call system, replacing the old DECT system.
The study also included verification of the minimum separation distance between cell phones/DECT phones and hospital equipment.
Conclusion of the study
The study concluded that the minimum separation distance for cell phones and DECT phones that had previously been recommended to hospital staff was correct. However, the study revealed that TETRA radios have a higher transmitting power and therefore require a larger safety distance from life sustaining hospital equipment to avoid interference.
Furthermore, the investigations showed that a well-functioning DAS facility clearly lowers the EMF levels around life sustaining equipment to an acceptable level.