Справочник Пользователя для Samsung SPH-a740

Most modern electronic equipment is shielded from radio frequency 
(RF) signals. However, RF signals from wireless phones may affect 
inadequately shielded electronic equipment.
RF signals may affect improperly installed or inadequately shielded 
electronic operating systems and/or entertainment systems in motor 
vehicles. Check with the manufacturer or their representative to 
determine if these systems are adequately shielded from external RF 
signals. Also check with the manufacturer regarding any equipment 
that has been added to your vehicle.
Consult the manufacturer of any personal medical devices, such as 
pacemakers and hearing aids, to determine if they are adequately 
shielded from external RF signals.

Note:

Always turn off the phone in health care facilities and request 

permission before using the phone near medical equipment.

Turn off your phone before boarding any aircraft. To prevent possible 
interference with aircraft systems, the U.S. Federal Aviation 
Administration (FAA) regulations require you to have permission 
from a crew member to use your phone while the plane is on the 
ground. To prevent any risk of interference, FCC regulations prohibit 
using your phone while the plane is in the air.

To avoid interfering with blasting operations, turn off your phone 
when in a blasting area or in other areas with signs indicating that 
two-way radios should be turned off. Construction crews often use 
remote-control RF devices to set off explosives.