Zte X500 Manual page 34

Switch off your device when in any area with a potentially explosive
atmosphere, and obey all signs and instructions. Potentially
explosive atmospheres include areas where you would normally be
advised to turn off your vehicle engine. Sparks in such areas could
cause an explosion or fire resulting in bodily injury or even death.
Switch off the device at refueling points such as near gas pumps at
service stations. Observe restrictions on the use of radio
equipment in fuel depots, storage, and distribution areas; chemical
plants; or where blasting operations are in progress. Areas with a
potentially explosive atmosphere are often, but not always, clearly
marked. They include below deck on boats, chemical transfer or
storage facilities and areas where the air contains chemicals or
particles such as grain, dust, or metal powders. You should check
with the manufacturers of vehicles using liquefied petroleum gas
(such as propane or butane) to determine if this device can be
safely used in their vicinity.