Phonak Audeo P Series User Manual page 63

The batteries used in these hearing aids should not exceed
1.5 Volts. Please do not use silver-zinc or Li-ion (lithium-ion)
rechargeable batteries as these may cause severe damage to
your hearing aids. The table in chapter 5 explains exactly
which type of battery your particular hearing aids require.
Remove the battery if you are not using your hearing aid for
a long period of time.
Special medical or dental examination including radiation
described below, may adversely affect the correct
functioning of your hearing aids. Remove and keep them
outside the examination room/area before undergoing:
Medical or dental examination with X-ray (also CT scan).
Medical examinations with MRI/NMRI scans, generating
magnetic fields.
Hearing aids don't need to be removed when passing
security gates (airports etc.). If X-ray is used at all, it will be
in very low doses, and will not affect the hearing aids.
Do not use your hearing aid in areas where electronic
equipment is prohibited.
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