Mobile phone ban to be lifted in hospitals

The Scotsman reports that the mobile phone ban is to be lifted in hospitals.

One thing that has puzzled me. If the equipment is potentially sensitive to a mobile phone being used nearby and transmitting a signal to a very large receiver, surely the very large transmitter sending a signal strong enough to be picked up by a very small receiver (the mobile) would also have had an effect.

So if the hospitals were complaining about interference from mobile phones, why were they not complaining about the outbound signal from the masts at the same time?

Can anyone explain the physics?