There are relatively few places left where mobile phones are not used, such as in hospitals and on aeroplanes. But even here, things may soon be changing.
If you have ever used a mobile phone near any electronic equipment, you will be familiar with the sound of its signal interfering with a microphone or a nearby speaker.
Use of mobiles is generally not allowed near hospital equipment
Mobiles clearly cause interference.
But could that really be a problem in a place like a hospital, where you can find sensitive electronic equipment?
Research from several organisations has concluded that although mobiles do interfere with some monitor displays and pacemakers, this is only at very close range.
The majority of hospital equipment is unaffected, as Dr Simon Minkoff, a specialist registrar in anaesthesia, explains.
"In my experience - in many hospitals, mostly in critical care units such as intensive care and theatre environments - I've never seen any significant interference from mobile phones on monitoring or drug delivery equipment such as pumps."
He adds that research carried out by a government agency into medical equipment and radio interference found the risk of any interference from mobile phones was insignificant.
"Radio equipment, such as that used by the emergency services, or hospital porters and security, for example the two-way radio, is 10 times more likely to interfere with medical equipment than the mobile phone that you or I might use today."
Dr Minkoff says the British Medical Association (BMA) actually wants hospitals to embrace wireless technology to improve patient care.
"The BMA is not just calling for mobile phones to be allowed to be used in hospitals, but is also talking about wireless networking for a PDA or laptop computer, so we can communicate more efficiently."
Another area where we are asked to turn off our mobiles is on boarding aeroplanes, because they could interfere with the in-flight equipment.
Soon Airbus passengers could be able to talk freely on their mobiles
Guy Kewney, of Mobile Phone Watcher, says: "Radio interference could hurt an aeroplane by putting electricity on wires which shouldn't have it.
"That could be any wire on an old bit of equipment. So it just depends upon what the equipment is, if your plane is old enough and if the equipment is unshielded."
The main problem is that, when the nearest mast is a long way away, a mobile phone will boost its transmitter power to try to improve reception.
A whole plane's worth of mobiles all clamouring for the faintest whiff of a signal, and all at maximum power, certainly could cause a bit of a buzz.
Several companies have been working on ways around this state of in-flight incommunicado. One of them is the Airbus, one of the biggest manufacturers of aircraft in the world.
Plane of the future
Airbus is so convinced that the risk from mobile phones is minimal it has just announced plans for an in-flight mobile service on future plane designs.
The theory is that if your phone cannot get close to a transmitter, you bring the transmitter closer to the phone.
So Airbus is putting it on the plane itself.
David Velupillai, of Airbus, says: "We have our own ground station, but this time it's mounted within the aircraft.
"It's called a pico-cell and it is telling all the phones onboard the aircraft to limit the signal they're putting out.
"It's telling them: 'don't shout, I can hear you, just give me the minimum signal needed.'"
With phones transmitting at minimum power they will not interfere with any on-board equipment.
Guy Kewney believes people will respond to being able to use phones freely on an aeroplane much as they would anywhere else, provided they are not overcharged for it.
Some may feel a plane is one of the few places left where we are spared the musical medley of ring tones and loud conversations, and that a plane full of ringing phones is undesirable.
But Kewney suspects the disturbance made by a phone on a plane is very much less than anywhere else because planes are so noisy.
"If my phone rings and you're three feet back, you probably won't hear it.
"So I don't think it's going to be a significant problem socially, unless you're just getting off to sleep and the person next to you rings.
"That could annoy you, but that's annoying anywhere."
The service could go live as early as 2006. So it may not be long before we will be hearing a rather familiar sound at 20,000 feet: "I'm on the plane. I'm ON THE PLANE!"
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