We allow cell phones and i don't recall any problems concernings them (as regards to the pateient's health).
The cell phones actually were a relief to our work, because this way the number of calls from the exterior diminuished drastically. The relatives and friends find how they're feeling on first hand. There are some cases we have to tell the patients to reduce the volume of the sound.
I remember one patient that had her phone alarm clock ringing every 3 a.m., because she didn't knew how to disable that option! It had been doing that for the last 4 months!
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